Journal articles: 'Carbonyle'

1

Laurence, Christian, Michel Berthelot, and Maryvonne Helbert. "Stéréochimie de la liaison hydrogène sur le groupe carbonyle." Spectrochimica Acta Part A: Molecular Spectroscopy 41, no. 7 (January 1985): 883–92. http://dx.doi.org/10.1016/0584-8539(85)80220-8.

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2

Grandi, M., C. Assoun, G. Numico, and R. Canuto. "Iron-carbonyle: Preliminary results on breast and lung cancer." Biomedicine & Pharmacotherapy 47, no. 6-7 (November 1993): 279. http://dx.doi.org/10.1016/0753-3322(93)90210-c.

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Darchen, André, El Kbir Lhadi, and Henri Patin. "Etude cinétique de la réaction thermique de remplacement d'un carbonyle, par un ligand L, dans des complexes carbéniques binucléaires du fer carbonyle." Journal of Organometallic Chemistry 363, no. 1-2 (March 1989): 137–49. http://dx.doi.org/10.1016/0022-328x(89)88047-7.

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4

Guihéneuf, Georges, Christian Bénard, Abdeljalil Lachkar, and Maryvonne Luçon. "Interaction entre le groupe carbonyle et les hétéroatomes des acétates d'éthyle α-substitués." Canadian Journal of Chemistry 63, no. 9 (September 1, 1985): 2343–48. http://dx.doi.org/10.1139/v85-388.

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Infrared spectra of ethyl α-aminoacetates show three bands in the carbonyl region. Solvent effects show that this is not due to Fermi resonance. These spectra can be interpreted using a model that considers the interactions between the nitrogen lone pair and the carbonyl group. The existence of an equilibrium between the conformers caused by the different orientations of the nitrogen lone pair with respect to the carbonyl group can be forecast. This model enables the interpretation of the carbonyl absorptions of the α-substituted (methoxy and ethoxy) ethyl acetates.

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5

Kern, J. M., D. Martina, and M. P. Heitz. "Methode electrochimique de liberation d'un ligand organique de son complexe de fer carbonyle." Tetrahedron Letters 26, no. 6 (January 1985): 737–40. http://dx.doi.org/10.1016/s0040-4039(00)89124-8.

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6

van Meerssche, M., P. Piret, J. Meunier-Piret, and Y. Degrève. "Structure Moléculaire de Trois Complexes du Fer-Carbonyle Avec L'Acétylène et Ses Dérivés." Bulletin des Sociétés Chimiques Belges 73, no. 9-10 (September 2, 2010): 824–32. http://dx.doi.org/10.1002/bscb.19640730912.

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7

ROUSSELLE, D., and F. RAVEL. "Etude du rôle de la microstructure sur les propriétés électromagnétiques du fer ex-carbonyle." Le Journal de Physique IV 02, no. C3 (December 1992): C3–65—C3–71. http://dx.doi.org/10.1051/jp4:1992309.

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8

Patin, Henri, Boguslaw Misterkiewicz, Jean-Yves Le Marouille, and Abdelhamid Mousser. "Complexes binucleaires de fer carbonyle liaison σ-metal-carbone: Synthese, etude structurale et proprietes." Journal of Organometallic Chemistry 314, no. 1-2 (October 1986): 173–84. http://dx.doi.org/10.1016/0022-328x(86)80362-x.

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9

Kreiter, Cornelius G., Wolfgang Michels, and Martin Wenz. "Gehinderte Ligandbewegungen in Übergangsmetallkomplexen, XXXIII. (η2- und η4-Dien)[2-(η5-cyclopentadienyl)ethyl]molybdän-Carbonyle." Chemische Berichte 119, no. 6 (June 1986): 1994–2005. http://dx.doi.org/10.1002/cber.19861190620.

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10

Piron, J., P. Piret, J. Meunier-Piret, and M. van Meerssche. "Complexes du Fer-Carbonyle Avec L'acétylène et ses Dérivés. V. Structure de Fe2(CO)6 · (CH3C2CH3)2CO." Bulletin des Sociétés Chimiques Belges 78, no. 1-2 (September 2, 2010): 121–30. http://dx.doi.org/10.1002/bscb.19690780115.

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11

Michel, Gilbert. "Contribution a la Spectrométrie Raman - III Etude de la fréquence de vibration de la raie raman du Carbonyle." Bulletin des Sociétés Chimiques Belges 68, no. 10-12 (September 1, 2010): 643–66. http://dx.doi.org/10.1002/bscb.19590681011.

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12

Kiremire, Enos Masheija Rwantale. "Unusual underground Capping Carbonyl Clusters of Palladium." International Journal of Chemistry 8, no. 1 (January 21, 2016): 145. http://dx.doi.org/10.5539/ijc.v8n1p145.

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<p>Transition metal carbonyls form unlike boranes a wide range of clusters. High nuclearity carbonyl clusters have a tendency to form capped clusters. Using the method of series explained in this paper, many capped carbonyl clusters have been identified for group 7, 8, 9 and 10 transition metals such as rhenium, osmium, rhodium and palladium. The series have discovered that palladium form exclusively capped carbonyl clusters. Furthermore, it has been discovered that some of the capped clusters have negative nuclear closo function. Such carbonyls have been regarded as capping underground. This paper presents the unique characteristic of high nuclearity capping carbonyl clusters of palladium.</p>

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13

Hellén, H., H. Hakola, A. Reissell, and T. M. Ruuskanen. "Carbonyl compounds in boreal coniferous forest air in Hyytiälä, Southern Finland." Atmospheric Chemistry and Physics 4, no. 7 (September 8, 2004): 1771–80. http://dx.doi.org/10.5194/acp-4-1771-2004.

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Abstract. A variety of C1-C12 carbonyl compounds were measured in the air of a boreal coniferous forest located in Hyytiälä, Southern Finland. 24-hour samples were collected during March and April in 2003 using DNPH (2,4-dinitrophenyl hydrazine) coated C18-cartridges and analyzed by liquid chromatography-mass spectrometry (LC-MS). Altogether 22 carbonyl compounds were quantified. The most abundant carbonyls were acetone (24-hour average 1340ng/m3), formaldehyde (480ng/m3) and acetaldehyde (360ng/m3). Concentrations of monoterpene reaction products nopinone (9ng/m3) and limona ketone (5ng/m3) were low compared to the most abundant low molecular weight carbonyls. Trajectory analysis showed that highest concentrations of carbonyls were measured in the air masses coming from the East and the lowest in the air masses cycled long time over Scandinavia. The total concentration of carbonyl compounds in Hyytiälä in March/April 2003 was much higher than the concentration of aromatic hydrocarbons and monoterpenes in April 2002. Scaling the concentrations against reactivity with the OH-radical showed, that in spite of relatively low ambient concentrations higher molecular weight aldehydes contribute significantly to the total OH-reactive mass of carbonyls. The impact of carbonyl compounds on OH-radical chemistry is important. Contribution of carbonyls as an OH sink is comparable to that of NO2 and higher than monoterpenes and aromatic hydrocarbons. Lifetimes of the measured carbonyls with respect to reactions with OH radicals, ozone (O3), and nitrate (NO3) radicals as well as photolysis were estimated. The main sink reactions for most of the carbonyl compounds in Hyytiälä in springtime are expected to be reactions with the OH radical and photolysis. For 6-methyl-5-hepten-2-one and limona ketone also reactions with ozone are important. The sources of carbonyl compounds are presently highly uncertain. Based on the comparisons with urban concentrations the direct anthropogenic emissions are not as important as secondary biogenic and anthropogenic sources or primary biogenic sources in Hyytiälä.

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14

Mannello, Ferdinando, Gaetana A. Tonti, and Virginia Medda. "Protein Oxidation in Breast Microenvironment: Nipple Aspirate Fluid Collected from Breast Cancer Women Contains Increased Protein Carbonyl Concentration." Analytical Cellular Pathology 31, no. 5 (January 1, 2009): 383–92. http://dx.doi.org/10.1155/2009/545896.

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Background: Protein carbonyl levels are the most frequently used biomarker of protein oxidation in several human diseases, including cancer. Breast cancer, a worldwide disease with increasing incidence, develops from ductal/lobular epithelium from which nipple aspirate fluid can be collected and analysed to assess tissue metabolic activity. Our aims were to perform an exploratory investigation on the protein carbonyl accumulation in breast secretions from healthy and cancer patients and its correlation with lipid peroxidation markers.Methods: Protein carbonyls were determined by ELISA in 288 Nipple Aspirate Fluids (NAF) from Control, Pre-malignant and Cancer patients.Results: Significantly higher protein carbonyl concentration was found in NAF from breast cancer (BC) patients compared to Control subjects. Cancer patients accumulated in NAF significantly higher levels of carbonyls in post-menopausal condition. A significant inverse relationship between carbonyls and 8-F2α-isoprostanes in NAF was found in Cancer patients. NAF levels of protein carbonyls are significantly higher in women with pre-malignant conditions than in healthy subjects.Conclusions: Our results support the hypothesis that oxidative stress in breast microenvironment plays a role in breast cancer; measurement of protein and lipid oxidative products in NAF may improve the identification of women at increased breast cancer risk.

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15

Depireux, J. "Étude de la Vibration Caractéristique du Groupe Carbonyle de quelques Cétones et de quelques Aldéhydes par Spectrométrie D'Absorption Infra-Rouge." Bulletin des Sociétés Chimiques Belges 66, no. 1 (September 1, 2010): 218–28. http://dx.doi.org/10.1002/bscb.19570660117.

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16

Chen, W. T., M. Shao, S. H. Lu, M. Wang, and L. M. Zeng. "Understanding primary and secondary sources of ambient carbonyl compounds in Beijing using the PMF model." Atmospheric Chemistry and Physics Discussions 13, no. 6 (June 13, 2013): 15749–81. http://dx.doi.org/10.5194/acpd-13-15749-2013.

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Abstract. Carbonyls are important intermediates in atmospheric photochemistry. To determine the relative contributions of primary and secondary carbonyl sources in Beijing, carbonyls and other trace gases were measured at Peking University in winter and summer. The Positive Matrix Factorization (PMF) model was used for source apportionment. As volatile organic compounds (VOCs) will undergo photochemical processes in the atmosphere, and such processes may interfere with factors identification, the relationships between the contributions of the resolved PMF factors to each non-methane hydrocarbon (NMHC) species and its kOH value were used to distinguish between photochemically aged factors and fresh factors. As the result of PMF, five factors were resolved in winter, and two of them were identified as sources of photochemically aged emissions. In summer, four factors were resolved, including an aged factor. Carbonyls in the aged factors were simulated by NMHCs consumption and the corresponding carbonyl production yields, and the simulated abundances agreed well with the results obtained by PMF. The source apportionment results indicated that secondary formation was the major source of carbonyls in both seasons, with the contribution of 51.2% and 46.0%. For the three major carbonyl species, primary anthropogenic sources contributed 28.9% and 32.3% to ambient formaldehyde, 53.7% and 41.6% to acetaldehyde, 68.1% and 56.2% to acetone in winter and summer, respectively.

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17

Chen, W. T., M. Shao, S. H. Lu, M. Wang, L. M. Zeng, B. Yuan, and Y. Liu. "Understanding primary and secondary sources of ambient carbonyl compounds in Beijing using the PMF model." Atmospheric Chemistry and Physics 14, no. 6 (March 26, 2014): 3047–62. http://dx.doi.org/10.5194/acp-14-3047-2014.

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Abstract. Carbonyl compounds are important intermediates in atmospheric photochemistry. To explore the relative contributions of primary and secondary carbonyl sources, carbonyls and other volatile organic compounds (VOCs) were measured at an urban site in both winter and summer in Beijing. The positive matrix factorization (PMF) model was used for source apportionment of VOCs. As VOCs undergo photochemical processes in the atmosphere, and such processes may interfere with factor identification, the relationships between the contributions of the resolved PMF factors to each non-methane hydrocarbon (NMHC) species and its kOH value were used to distinguish fresh factors and photochemically aged factors. As the result of PMF, five factors were resolved in winter, and two of them were identified as photochemically aged emissions. In summer, four factors were resolved, including one aged factor. Carbonyls abundances from aged factors were simulated by VOCs consumption and the corresponding carbonyl production yields, and the simulated abundances agreed well with the results obtained by the PMF model. The source apportionment results indicated that secondary formation was the major source of carbonyls in both winter and summer, with the respective contributions of 51.2% and 46.0%. For the three major carbonyl species, primary anthropogenic sources contributed 28.9% and 32.3% to ambient formaldehyde, 53.7% and 41.6% to acetaldehyde, 68.1% and 56.2% to acetone in winter and summer, respectively.

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18

Schaefer, Henry F., and R. Bruce King. "Unsaturated binuclear homoleptic metal carbonyls M2(CO)x (M = Fe, Co, Ni; x = 5, 6, 7, 8). Are multiple bonds between transition metals possible for these molecules?" Pure and Applied Chemistry 73, no. 7 (July 1, 2001): 1059–73. http://dx.doi.org/10.1351/pac200173071059.

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Modern density functional methods, which yield geometrical parameters and energies close to experimental values for known metal carbonyls such as Fe(CO)5 and Fe2(CO)9, have been extended to unsaturated binary binuclear metal carbonyls. Novel optimized structures have been discovered containing metalmetal multiple bonds, four-electron bridging carbonyl groups, and metal electronic configurations less than 18 electrons.

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19

Duong, Huy Huu, Thu Huong Minh Dang, and Hien Thi To. "Partition of the carbonyl compounds between the indoor and outdoor air at residental areas in District 5, Ho Chi Minh City." Science and Technology Development Journal 19, no. 2 (June 30, 2016): 94–106. http://dx.doi.org/10.32508/stdj.v19i2.807.

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Indoor air pollution, especially for the air toxic compounds such as carbonyls, is the most common issue in large cities. Indoor and outdoor air samples were simultaneously collected at six homes to estimate the pollution levels of carbonyl compounds at some points in the residential area, Ho Chi Minh City. The gaseous carbonyls were measured in the period of August and September, 2011 corresponding to the rainy season. The results showed that formaldehyde, acetaldehyde and acetone were the most abundant carbonyls in both indoor and outdoor air, accounted 80 % of the interested compounds, followed by propionaldehyde and benzaldehyde. In the outdoor air, the mean concentrations of formaldehyde, acetaldehyde and acetone were 15.21±6.42, 13.77±7.63, 12.11±11.72 μg.m-3, respectively. Meanwhile, the indoor concentrations were 25.45±19.49, 26.21±13.03 and 22.12±18.08 μg.m-3 for formaldehyde, acetaldehyde and acetone, respectively. Formaldehyde/acetaldehyde and acetaldehyde/ propionaldehyde ratios were 2.23±1.41 and 6.09±5.00, respestively, indicating that main sources of outdoor carbonyls came from the anthropogenic source. The mean carbonyl concentrations of the present study compared with those of other countries showed that indoor carbonyls were similar to other studies, but outdoor carbonyls were much higher. In addition, most of the indoor/outdoor ratios were slightly higher than 1 and levels of benzaldehyde and tolualdehyde were a little high in the indoor air. These results indicated that the indoor carbonyls were strongly affected by the outdoor air infiltration.

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20

Wang, Hongli, Xuan Zhang, and Zhongming Chen. "Development of DNPH/HPLC method for the measurement of carbonyl compounds in the aqueous phase: applications to laboratory simulation and field measurement." Environmental Chemistry 6, no. 5 (2009): 389. http://dx.doi.org/10.1071/en09057.

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Environmental context. Carbonyl compounds, a class of oxygenated organic matter, are crucial participants in atmospheric processes. Recently, studies have shown that the aqueous-phase processes of carbonyls have an important contribution to the formation of secondary organic aerosol (SOA), which is considered to have a significant impact on global climate change and human health. We developed the classical DNPH/HPLC method to characterise the aqueous-phase carbonyls, especially methacrolein, methyl vinyl ketone, glyoxal, and methylglyoxal, which are important precursors of SOA, in order to better understand the pathways of SOA formation in the atmosphere. Abstract. The DNPH/HPLC method for characterising monocarbonyls and dicarbonyls in the aqueous phase has been developed. A series of experiments have been carried out using eight atmospheric ubiquitous carbonyl compounds as model dissolved compounds in both acetonitrile and water solution to obtain the optimal derivatisation and analysis qualifications. Compared with the analysis of carbonyls dissolved in acetonitrile, the influence of acidity on the derivatisation efficiency should be carefully considered in determining carbonyls in water and the optimal acidity is pH 2.0. We find that methyl vinyl ketone (MVK) transforms to crotonaldehyde during the derivatisation reaction. This transformation can be controlled to a minor degree by increasing the mixing ratio of DNPH to MVK up to 100 : 1. This improved method has been satisfactorily applied to laboratory simulations and field measurements for better understanding the carbonyl chemistry in the atmosphere.

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21

Hellén, H., H. Hakola, A. Reissell, and T. M. Ruuskanen. "Carbonyl compounds in boreal coniferous forest air in Hyytiälä, Southern Finland." Atmospheric Chemistry and Physics Discussions 4, no. 3 (June 3, 2004): 2991–3011. http://dx.doi.org/10.5194/acpd-4-2991-2004.

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Abstract. A variety of C1-C12 carbonyl compounds were measured in the air of a boreal coniferous forest located in Hyytiälä, Southern Finland. 24-h samples were collected during March and April in 2003 using DNPH (2,4-dinitrophenyl hydrazine) coated C18-cartridges and analyzed by liquid chromatography-mass spectrometry (LC-MS). Altogether 22 carbonyl compounds were quantified. The most abundant carbonyls were acetone (24-h average 1340 ng/m3), formaldehyde (480 ng/m3) and acetaldehyde (360 ng/m3). In contrast, scaling of concentrations against reactivity with the hydroxyl (OH) radical significantly increased the contribution of larger aldehydes and ketones (e.g. decanal, octanal and 6-methyl-5-hepten-2-one). Concentrations of monoterpene reaction products nopinone (9 ng/m3) and limona ketone (5 ng/m3) were low compared to the most abundant low molecular weight carbonyls. The total concentration of carbonyl compounds in Hyytiälä in April/March 2003 was much higher than the concentration of aromatic hydrocarbons and monoterpenes in April 2002. Lifetimes of the measured carbonyls with respect to reactions with OH radicals, ozone (O3), and nitrate (NO3) radicals as well as photolysis were estimated. The main sinks for most of the carbonyl compounds in Hyytiälä in springtime are expected to be reactions with the OH radical and photolysis. For 6-methyl-5-hepten-2-one and limona ketone also reactions with ozone are important. The sources of carbonyl compounds are presently highly uncertain. Due to the relatively short lifetimes of aldehydes and ketones, secondary biogenic and anthropogenic sources, that is oxidation of volatile organic compounds, and primary biogenic sources are expected to dominate in Hyytiälä.

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22

Singh, Manisha, and Ravi Bhushan. "A modification of a conventional technique for the synthesis of hydrazones of racemic carbonyls: prevention of spontaneous chiral inversion." RSC Advances 5, no. 128 (2015): 105719–26. http://dx.doi.org/10.1039/c5ra19904b.

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23

Rao, Xin, Reiko Kobayashi, Rochelle White-Morris, Reggie Spaulding, Paul Frazey, and M. Judith Charles. "GC/ITMS Measurement of Carbonyls and Multifunctional Carbonyls in PM2.5 Particles Emitted from Motor Vehicles." Journal of AOAC INTERNATIONAL 84, no. 3 (May 1, 2001): 699–705. http://dx.doi.org/10.1093/jaoac/84.3.699.

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Abstract A method was developed and tested to identify and quantitate carbonyls and multifunctional carbonyls in fine particulate matter (PM2.5; <2.5 μm aerodynamic diameter). The method relies on ultrasonic extraction of particulate matter on filters at −8°C; derivatization with O-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine (PFBHA), and PFBHA along with bis (trimethylsilyl) trifluoroacetamide (BSTFA); and detection of the derivatives by gas chromatography/ion trap mass spectrometry. Ultrasonic extraction of model compounds from enriched particles was affected by solvent polarity (water > methylene chloride > toluene–isopropanol (2 + 1, v/v). Water provided the highest recovery for dihydroxy acetone, pyruvic acid, and hydroxy acetone, compared to methylene chloride, and toluene–isopropanol. Lowering the ultrasonication bath temperature from 0° to −8°C improved the recoveries of the less water soluble and more volatile species—methacrolein, methyl vinyl ketone, 2,3-butanedione, and tolualdehyde. The power of the method was demonstrated by identification and quantitation of carbonyls and multifunctional carbonyls in sample extracts of fine particulate matter (PM2.5) collected in the Caldecott tunnel, CA. The identities of crotonaldehyde, 2,3-butanedione, glyoxal, 9H-fluoren-9-one, glycolaldehyde, glyoxylic acid, levulinic acid, and 3-hydroxybenzaldehyde were confirmed by comparing the relative retention time and mass spectra of the analyte in the sample extract with an authentic standard. Quantitation of crotonaldehyde, glyoxal, 2,3-butanedione, glyoxylic acid, and levulinic acid was accomplished. This is the first report of glyoxylic acid, levulinic acid, and 3-hydroxybenzaldheyde in PM2.5 particles sampled in a roadway tunnel. It is also the first report of a C10 carbonyl with the molecular formula of C10H16O2, a hydroxy carbonyl with the molecular formula of C17H21NO2, and a hydroxy or dihydroxy carbonyl with the molecular formula of C16H14O2 or C9H10O3. The high-molecular weight hydroxy carbonyls, which were found only in the heavy-duty (diesel) bore, may be tracers of diesel emissions in air.

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24

Ludwig, Jacob R., Rebecca B. Watson, Daniel J. Nasrallah, Joseph B. Gianino, Paul M. Zimmerman, Ren A. Wiscons, and Corinna S. Schindler. "Interrupted carbonyl-olefin metathesis via oxygen atom transfer." Science 361, no. 6409 (September 27, 2018): 1363–69. http://dx.doi.org/10.1126/science.aar8238.

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Some of the simplest and most powerful carbon-carbon bond forming strategies take advantage of readily accessible ubiquitous motifs: carbonyls and olefins. Here we report a fundamentally distinct mode of reactivity between carbonyls and olefins that differs from established acid-catalyzed carbonyl-ene, Prins, and carbonyl-olefin metathesis reaction paths. A range of epsilon, zeta-unsaturated ketones undergo Brønsted acid–catalyzed intramolecular cyclization to provide tetrahydrofluorene products via the formation of two new carbon-carbon bonds. Theoretical calculations and accompanying mechanistic studies suggest that this carbocyclization reaction proceeds through the intermediacy of a transient oxetane formed by oxygen atom transfer. The complex polycyclic frameworks in this product class appear as common substructures in organic materials, bioactive natural products, and recently developed pharmaceuticals.

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Moldoveanu, S., W. Coleman, and J. Wilkins. "Determination of Carbonyl Compounds in Exhaled Cigarette Smoke." Beiträge zur Tabakforschung International/Contributions to Tobacco Research 22, no. 5 (June 1, 2007): 346–57. http://dx.doi.org/10.2478/cttr-2013-0841.

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AbstractThis paper presents the findings on a quantitative evaluation of carbonyl levels in exhaled cigarette smoke from human subjects. The cigarettes evaluated include products with 5.0 mg ‘tar’, 10.6 mg ‘tar’ and 16.2 mg ‘tar’, where ‘tar’ is defined as the weight of total wet particulate matter (TPM) minus the weight of nicotine and water, and the cigarettes are smoked following U.S. Federal Trade Commission (FTC) recommendations. The measured levels of carbonyls in the exhaled smoke were compared with calculated yields of carbonyls in the inhaled smoke and a retention efficiency was obtained. The number of human subjects included a total of ten smokers for the 10.6 mg ‘tar’, five for the 16.2 mg ‘tar’, and five for the 5.0 mg ‘tar’ product, each subject smoking three cigarettes. The analyzed carbonyl compounds included several aldehydes (formaldehyde, acetaldehyde, acrolein, propionaldehyde, crotonaldehyde and n-butyraldehyde), and two ketones (acetone and 2-butanone). The smoke collection from the human subjects was vacuum assisted. Exhaled smoke was collected on Cambridge pads pretreated with a solution of dinitrophenylhydrazine (DNPH) followed by high performance liquid chromatography (HPLC) analysis of the dinitrophenylhydrazones of the carbonyl compounds. The cigarette butts from the smokers were collected and analyzed for nicotine. The nicotine levels for the cigarette butts from the smokers were used to calculate the level of carbonyls in the inhaled smoke, based on calibration curves. These were generated separately by analyzing the carbonyls in smoke and the nicotine in the cigarette butts obtained by machine smoking under different puffing regimes. The comparison of the level of carbonyl compounds in exhaled smoke with that from the inhaled smoke showed high retention of all the carbonyls. The retention of aldehydes was above 95% for all three different ‘tar’ levels cigarettes. The ketones were retained with a slightly lower efficiency. Acetone was retained in the range of 90% to 95%. The retention for 2-butanone showed a larger scatter compared to other results but it also appeared to be slightly less absorbed than the aldehydes, with an average retention around 95%. The retention of acetaldehyde and acetone by human smokers was previously reported in literature and the findings from this study are in very good agreement with these result.

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Méndez, Lucía, Silvia Muñoz, Bernat Miralles-Pérez, Maria Rosa Nogués, Sara Ramos-Romero, Josep Lluis Torres, and Isabel Medina. "Modulation of the Liver Protein Carbonylome by the Combined Effect of Marine Omega-3 PUFAs and Grape Polyphenols Supplementation in Rats Fed an Obesogenic High Fat and High Sucrose Diet." Marine Drugs 18, no. 1 (December 30, 2019): 34. http://dx.doi.org/10.3390/md18010034.

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Diet-induced obesity has been linked to metabolic disorders such as cardiovascular diseases and type 2 diabetes. A factor linking diet to metabolic disorders is oxidative stress, which can damage biomolecules, especially proteins. The present study was designed to investigate the effect of marine omega-3 polyunsaturated fatty acids (PUFAs) (eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)) and their combination with grape seed polyphenols (GSE) on carbonyl-modified proteins from plasma and liver in Wistar Kyoto rats fed an obesogenic diet, namely high-fat and high-sucrose (HFHS) diet. A proteomics approach consisting of fluorescein 5-thiosemicarbazide (FTSC) labelling of protein carbonyls, visualization of FTSC-labelled protein on 1-DE or 2-DE gels, and protein identification by MS/MS was used for the protein oxidation assessment. Results showed the efficiency of the combination of both bioactive compounds in decreasing the total protein carbonylation induced by HFHS diet in both plasma and liver. The analysis of carbonylated protein targets, also referred to as the ‘carbonylome’, revealed an individual response of liver proteins to supplements and a modulatory effect on specific metabolic pathways and processes due to, at least in part, the control exerted by the supplements on the liver protein carbonylome. This investigation highlights the additive effect of dietary fish oils and grape seed polyphenols in modulating in vivo oxidative damage of proteins induced by the consumption of HFHS diets.

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Kutschy, Peter, Mojmír Suchý, Milan Dzurilla, Mitsuo Takasugi, and Vladimír Kováčik. "A New Approach to Imidazo[1,5-a]indole Derivatives." Collection of Czechoslovak Chemical Communications 65, no. 7 (2000): 1163–72. http://dx.doi.org/10.1135/cccc20001163.

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Reaction of indole-2-carbonyl isothiocyanate (1) with sodium methanethiolate afforded 1-thioxo-1H-imidazo[1,5-a]indol-3(2H)-one (3). Its methylation with methyl iodide in the presence of lithium hydride in dimethylformamide, or potassium carbonate in acetone resulted in the formation of corresponding S- and N-methyl derivatives 4 and 5. N-(Indole-2-carbonyl)thiocarbamates and N-(indole-2-carbonyl)thioureas prepared by treatment of isothiocyanate 1 with corresponding nucleophilic reagents were S-methylated with methyl iodide in acetone in the presence of potassium carbonate. The obtained N-(indole- 2-carbonyl) substituted thiocarbonimidates 15, 16 and isothioureas 17-20 afforded by treatment with lithium hydride in dimethylformamide the derivatives of imidazo[1,5-a]- indol-3-one 23-28 in 49-87% yields. Antifungal activity of the prepared compounds has been examined, using the fungus Bipolaris leersiae. 1-Methylsulfanyl-3H-imidazo-[1,5-a]- indol-3-one (4) exhibited the highest antifungal activity.

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Son, Yeongkwon, Clifford Weisel, Olivia Wackowski, Stephan Schwander, Cristine Delnevo, and Qingyu Meng. "The Impact of Device Settings, Use Patterns, and Flavorings on Carbonyl Emissions from Electronic Cigarettes." International Journal of Environmental Research and Public Health 17, no. 16 (August 5, 2020): 5650. http://dx.doi.org/10.3390/ijerph17165650.

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Health impacts of electronic cigarette (e-cigarette) vaping are associated with the harmful chemicals emitted from e-cigarettes such as carbonyls. However, the levels of various carbonyl compounds under real-world vaping conditions have been understudied. This study evaluated the levels of carbonyl compounds (e.g., formaldehyde, acetaldehyde, glyoxal, and diacetyl, etc.) under various device settings (i.e., power output), vaping topographies, and e-liquid compositions (i.e., base liquid, flavor types). The results showed that e-vapor carbonyl levels were the highest under higher power outputs. The propylene glycol (PG)-based e-liquids generated higher formaldehyde and acetaldehyde than vegetable glycerin (VG)-based e-liquids. In addition, fruit flavored e-liquids (i.e., strawberry and dragon fruit) generated higher formaldehyde emissions than mint/menthol and creamy/sweet flavored e-liquids. While single-top coils formed 3.5-fold more formaldehyde per puff than conventional cigarette smoking, bottom coils generated 10–10,000 times less formaldehyde per puff. In general, increases in puff volume and longer puff durations generated significantly higher amounts of formaldehyde. While e-cigarettes emitted much lower levels of carbonyl compounds compared to conventional cigarettes, the presence of several toxic carbonyl compounds in e-cigarette vapor may still pose potential health risks for users without smoking history, including youth. Therefore, the public health administrations need to consider the vaping conditions which generated higher carbonyls, such as higher power output with PG e-liquid, when developing e-cigarette product standards.

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Kawamura, K., K. Okuzawa, S. G. Aggarwal, H. Irie, Y. Kanaya, and Z. Wang. "Determination of gaseous and particulate carbonyls (glycolaldehyde, hydroxyacetone, glyoxal, methylglyoxal, nonanal and decanal) in the atmosphere at Mt. Tai." Atmospheric Chemistry and Physics Discussions 13, no. 1 (January 25, 2013): 2725–58. http://dx.doi.org/10.5194/acpd-13-2725-2013.

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Abstract. Gaseous and particulate semi-volatile carbonyl compounds were determined every three hours in the atmosphere of Mount Tai (elevation, 1534 m) in the North China Plain during 2–5, 23–24 and 25 June, 2006 under a clear sky condition. Using two-step filter cartridge in a series, particulate carbonyls were first collected on a quartz filter and then gaseous carbonyls were collected on a quartz filter impregnated with O-benzylhydroxylamine (BHA). After the two-step derivatization with BHA and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA), carbonyl derivatives were measured using a gas chromatography. The gaseous concentrations were obtained as follow: glycolaldehyde (range 0–1271 ng m−3, average 555 ng m−3), hydroxyacetone (0–707 ng m−3, 163 ng m−3), glyoxal (198–1396 ng m−3, 720 ng m−3), methylglyoxal (410–3170 ng m−3, 1376 ng m−3), n-nonanal (0–236 ng m−3, 71 ng m−3), and n-decanal (0–159 ng m−3, 31 ng m−3). These concentrations are among the highest ever reported in the urban and forest atmosphere. We found that gaseous carbonyls are more than 10 times more abundant than particulate carbonyls. Time-resolved variations of carbonyls did not show any a clear diurnal pattern, except for hydroxyacetone. We found that glyoxal, methylglyoxal and glycolaldehyde positively correlated with levoglucosan (a tracer of biomass burning), suggesting that a contribution from field burning of agricultural wastes (wheat crops) is significant for the bifunctional carbonyls in the atmosphere of Mt. Tai. Upward transport of the pollutants to the mountaintop from the low lands in the North China Plain is a major process to control the distributions of carbonyls in the upper atmosphere over Mt. Tai.

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Li, Jian, Liu Shui Yan, Chun Juan Xie, and Ling Na Li. "Diurnal Variations and Personal Exposures of Carbonyl Compounds in Different Types of Malls in Nanchang." Advanced Materials Research 726-731 (August 2013): 757–60. http://dx.doi.org/10.4028/www.scientific.net/amr.726-731.757.

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Diurnal variations and personal exposure of carbonyl compounds were investigated in four types of large shopping malls (including department store, supermarket, bookstore and furniture store) in urban district of Nanchang, China. The diurnal measurements both in the summer and winter showed that the concentrations of carbonyls exhibited a higher peak at the morning hour and a lower peak at the evening hour except for acetaldehyde, which obviously peaked at the afternoon hour in winter. The indoor concentrations of LMW carbonyl compounds were found higher than their outdoor counterparts with only a few exceptions. For some high molecular weight (HMW) carbonyls (C5) especially for benzaldehyde and p-Tolualdehyde which might have stronger outdoor source (e.g. vehicle exhaust), resulting in the Indoor/Outdoor ratios below 1. The personal exposures showed that large shopping malls in Nanchang were important microenvironment for exposure to formaldehyde and acetaldehyde.

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31

Johnson, Brian F. G. "The ligand polyhedral model approach to the mechanism of complete carbonyl exchange in [Rh4(CO)12] and [Rh6(CO)16]." Dalton Transactions 44, no. 37 (2015): 16602–10. http://dx.doi.org/10.1039/c4dt03360d.

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The Ligand Polyhedral Model (LPM) is applied to the carbonyl scrambling observed on the NMR timescale for the two cluster carbonyls [Rh₄(CO)₁₂] and [Rh₆(CO)₁₆].

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32

Li, Huidong, Hao Feng, Weiguo Sun, R. Bruce King, and Henry F. Schaefer. "Extreme Metal Carbonyl Back Bonding in Cyclopentadienylthorium Carbonyls Generates Bridging C2O2Ligands by Carbonyl Coupling." Inorganic Chemistry 52, no. 12 (May 30, 2013): 6893–904. http://dx.doi.org/10.1021/ic400797b.

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33

Healy, R. M., J. C. Wenger, A. Metzger, J. Duplissy, M. Kalberer, and J. Dommen. "Gas/particle partitioning of carbonyls in the photooxidation of isoprene and 1,3,5-trimethylbenzene." Atmospheric Chemistry and Physics 8, no. 12 (June 26, 2008): 3215–30. http://dx.doi.org/10.5194/acp-8-3215-2008.

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Abstract. A new denuder-filter sampling technique has been used to investigate the gas/particle partitioning behaviour of the carbonyl products from the photooxidation of isoprene and 1,3,5-trimethylbenzene. A series of experiments was performed in two atmospheric simulation chambers at atmospheric pressure and ambient temperature in the presence of NOx and at a relative humidity of approximately 50%. The denuder and filter were both coated with the derivatizing agent O-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine (PFBHA) to enable the efficient collection of gas- and particle-phase carbonyls respectively. The tubes and filters were extracted and carbonyls identified as their oxime derivatives by GC-MS. The carbonyl products identified in the experiments accounted for around 5% and 10% of the mass of secondary organic aerosol formed from the photooxidation of isoprene and 1,3,5-trimethylbenzene respectively. Experimental gas/particle partitioning coefficients were determined for a wide range of carbonyl products formed from the photooxidation of isoprene and 1,3,5-trimethylbenzene and compared with the theoretical values based on standard absorptive partitioning theory. Photooxidation products with a single carbonyl moiety were not observed in the particle phase, but dicarbonyls, and in particular, glyoxal and methylglyoxal, exhibited gas/particle partitioning coefficients several orders of magnitude higher than expected theoretically. These findings support the importance of heterogeneous and particle-phase chemical reactions for SOA formation and growth during the atmospheric degradation of anthropogenic and biogenic hydrocarbons.

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34

Healy, R. M., J. C. Wenger, A. Metzger, J. Duplissy, M. Kalberer, and J. Dommen. "Gas/particle partitioning of carbonyls in the photooxidation of isoprene and 1,3,5-trimethylbenzene." Atmospheric Chemistry and Physics Discussions 8, no. 2 (March 5, 2008): 4727–64. http://dx.doi.org/10.5194/acpd-8-4727-2008.

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Abstract. A new denuder-filter sampling technique has been used to investigate the gas/particle partitioning behaviour of the carbonyl products from the photooxidation of isoprene and 1,3,5-trimethylbenzene. A series of experiments was performed in two atmospheric simulation chambers at atmospheric pressure and ambient temperature in the presence of NOx and at a relative humidity of approximately 50%. The denuder and filter were both coated with the derivatizing agent O-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine (PFBHA) to enable the efficient collection of gas- and particle-phase carbonyls respectively. The tubes and filters were extracted and carbonyls identified as their oxime derivatives by GC-MS. The carbonyl products identified in the experiments accounted for around 5% and 10% of the mass of secondary organic aerosol formed from the photooxidation of isoprene and 1,3,5-trimethylbenzene respectively. Experimental gas/particle partitioning coefficients were determined for a wide range of carbonyl products formed from the photooxidation of isoprene and 1,3,5-trimethylbenzene and compared with the theoretical values based on standard absorptive partitioning theory. Photooxidation products with a single carbonyl moiety were not observed in the particle phase, but dicarbonyls, and in particular, glyoxal and methylglyoxal, exhibited gas/particle partitioning coefficients several orders of magnitude higher than expected theoretically. These findings support the importance of heterogeneous chemistry as a pathway for SOA formation and growth during the atmospheric degradation of anthropogenic and biogenic hydrocarbons.

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35

Son, Yeongkwon, Chiranjivi Bhattarai, Vera Samburova, and Andrey Khlystov. "Carbonyls and Carbon Monoxide Emissions from Electronic Cigarettes Affected by Device Type and Use Patterns." International Journal of Environmental Research and Public Health 17, no. 8 (April 17, 2020): 2767. http://dx.doi.org/10.3390/ijerph17082767.

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Dangerous levels of harmful chemicals in electronic cigarette (e-cigarette) aerosols were reported by several studies, but variability in e-cigarette design and use patterns, and a rapid development of new devices, such as JUUL, hamper efforts to develop standardized testing protocols and understand health risks associated with e-cigarette use. In this study, we investigated the relative importance of e-cigarette design, power output, liquid composition, puff topography on e-cigarette emissions of carbonyl compounds, carbon monoxide (CO), and nicotine. Four popular e-cigarette devices representing the most common e-cigarette types (e.g., cig-a-like, top-coil, ‘mod’, and ‘pod’) were tested. Under the tested vaping conditions, a top-coil device generated the highest amounts of formaldehyde and CO. A ‘pod’ type device (i.e., JUUL) emitted the highest amounts of nicotine, while generating the lowest levels of carbonyl and CO as compared to other tested e-cigarettes. Emissions increased nearly linearly with puff duration, while puff flow had a relatively small effect. Flavored e-liquids generated more carbonyls and CO than unflavored liquids. Carbonyl concentrations and CO in e-cigarette aerosols were found to be well correlated. While e-cigarettes emitted generally less CO and carbonyls than conventional cigarettes, daily carbonyl exposures from e-cigarette use could still exceed acute exposure limits, with the top-coil device potentially posing more harm than conventional cigarettes.

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Wang, Hongyan, Yaoming Xie, R. Bruce King, and Henry F. Schaefer. "Binuclear Iron Carbonyl Nitrosyls: Bridging Nitrosyls versus Bridging Carbonyls." Inorganic Chemistry 47, no. 8 (April 2008): 3045–55. http://dx.doi.org/10.1021/ic702077s.

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37

Fan, Qunchao, Hao Feng, Weiguo Sun, Huidong Li, Yaoming Xie, and R. Bruce King. "Carbonyl versus butadiene dissociation in binuclear butadiene cobalt carbonyls." Computational and Theoretical Chemistry 999 (November 2012): 129–37. http://dx.doi.org/10.1016/j.comptc.2012.08.026.

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38

Howe, Ethan Nam Wei, Mohan Bhadbhade, and Pall Thordarson. "Highly Sheared Anti-Parallel Dipolar Carbonyl···Carbonyl Interaction in the Crystal Packing of Strapped Crown-3-Pyromellitimide." Australian Journal of Chemistry 65, no. 10 (2012): 1384. http://dx.doi.org/10.1071/ch12085.

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Non-covalent dipolar interactions between pairs of carbonyls have been demonstrated to play a significant role in the crystal packing and formation of supramolecular structural architecture of small organic molecules. Under high dilution, the strapped crown-3-pyromellitimide 4 and macrocyclic crown-6-bispyromellitimide 5 were synthesised in concert and demonstrated selective molecular recognition towards Na+ and K+, respectively. The molecular structure of strapped crown-3-pyromellitimide 4 was solved using X-ray crystallography and an unusual highly sheared anti-parallel dipolar carbonyl···carbonyl interaction was observed in the crystal packing. The intermolecular interaction has a torsion angle of 44.1°, and deviates from the three idealised motifs reported in literature. This finding further highlights the importance and versatility of dipolar carbonyl···carbonyl interaction in the crystal packing of organic molecules.

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39

Newberry, R. W., and R. T. Raines. "Crystal structure ofN-(3-oxobutanoyl)-L-homoserine lactone." Acta Crystallographica Section E Crystallographic Communications 72, no. 2 (January 9, 2016): 136–39. http://dx.doi.org/10.1107/s2056989015024913.

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The structure and absolute configuration of the title compound, C8H11NO4, which is a known quorum-sensing modulator, have been determined. The molecule exhibits signs of an intramolecular attractive carbonyl–carbonyln→π*interaction between the amide and lactone ester groups, specifically – a short contact of 2.709 (2) Å between the amide oxygen atom and ester carbon atom, approach of the amide oxygen atom to the ester carbonyl group along the Bürgi–Dunitz trajectory, at 99.1 (1)°, and pyramidalization of the ester carbonyl group by 1.1 (1)°. Moreover, a similarn→π*interaction is observed for the amide carbonyl group approached by the ketone oxygen donor. These interactions apparently affect the conformation of the uncomplexed molecule, which adopts a different shape when bound to protein receptors. In the crystal, the molecules form translational chains along theaaxisviaN—H...O hydrogen bonds.

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40

Goutzourelas, N., D. Stagos, N. Demertzis, P. Mavridou, H. Karterolioti, S. Georgadakis, E. Kerasioti, et al. "Effects of polyphenolic grape extract on the oxidative status of muscle and endothelial cells." Human & Experimental Toxicology 33, no. 11 (September 8, 2014): 1099–112. http://dx.doi.org/10.1177/0960327114533575.

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A grape pomace extract enhanced antioxidant mechanisms in muscle and endothelial cells both in the absence and in the presence of oxidative stress-induced agent tert-butyl hydroperoxide (tBHP). In particular, muscle (C2C12) and endothelial (EA.hy926) cells were treated with the extract at noncytotoxic concentrations for 24 h, and the oxidative stress markers, total reactive oxygen species (ROS), glutathione (GSH), thiobarbituric reactive substances (TBARS), and protein carbonyl levels were assessed. The results showed that the grape extract treatment reduced significantly ROS, TBARS, and protein carbonyl levels and increased GSH in C2C12 cells, while it increased GSH and decreased protein carbonyl levels in EA.hy926 cells. In the presence of tBHP, the grape extract treatment in C2C12 cells reduced significantly ROS, TBARS, and protein carbonyls and increased GSH compared with tBHP alone treatment, while, in EA.hy926 cells, the extract decreased significantly TBARS and protein carbonyls but increased GSH. The antioxidant potency of the extract was different between muscle and endothelial cells suggesting that the antioxidant activity depends on cell type. Moreover, the antioxidant activity of the grape extract, in both cell lines, exerted, at least in part, through increase in GSH levels. The present work is the first to report the effects of grape extract shown for skeletal muscle cells.

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41

Chuealee, Rabkwan, Timothy S. Wiedmann, and Teerapol Srichana. "Thermotropic behavior of sodium cholesteryl carbonate." Journal of Materials Research 24, no. 1 (January 2009): 156–63. http://dx.doi.org/10.1557/jmr.2009.0027.

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Sodium cholesteryl carbonate ester (SCC) was synthesized, and its phase behavior was studied. The chemical structure was assessed by solid-state infrared spectroscopy based on vibration analysis. The wave number at 1705 and 1276 cm−1 corresponds to a carbonyl carbonate and O–C–O stretching of SCC, respectively. Molecular structure of SCC was further investigated with 1H and 13C NMR spectroscopy. The chemical shift, for the carbonyl carbonate resonance appeared at 155.5 ppm. A molecular mass of SCC was at m/z of 452. Differential scanning calorimetry (DSC), video-enhanced microscopy (VEM) together with polarized light microscopy, and small-angle x-ray scattering (SAXS) were used to characterize the phase behavior as a function of temperature of SCC. Liquid crystalline phase was formed with SCC. Based on the thermal properties and x-ray diffraction, it appears that SCC forms a structure analogous to the type II monolayer structure observed with cholesterol esters.

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42

Kawamura, K., K. Okuzawa, S. G. Aggarwal, H. Irie, Y. Kanaya, and Z. Wang. "Determination of gaseous and particulate carbonyls (glycolaldehyde, hydroxyacetone, glyoxal, methylglyoxal, nonanal and decanal) in the atmosphere at Mt. Tai." Atmospheric Chemistry and Physics 13, no. 10 (May 28, 2013): 5369–80. http://dx.doi.org/10.5194/acp-13-5369-2013.

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Abstract. Gaseous and particulate semi-volatile carbonyl compounds were determined every three hours in the atmosphere of Mount Tai (elevation, 1534 m) in the North China Plain during 2–5, 23–24 and 25 June 2006 under clear sky conditions. Using a two-step filter cartridge in a series, particulate carbonyls were first collected on a quartz filter and then gaseous carbonyls were collected on a quartz filter impregnated with O-benzylhydroxylamine (BHA). After the two-step derivatization with BHA and N,O-Bis(trimethylsilyl)trifluoroacetamide (BSTFA), carbonyl derivatives were measured using a gas chromatography. The gaseous concentrations were obtained as follow: glycolaldehyde (range 0–826 ng m−3, average 303 ng m−3), hydroxyacetone (0–579 ng m−3, 126 ng m−3), glyoxal (46–1200 ng m−3, 487 ng m−3), methylglyoxal (88–2690 ng m−3, 967 ng m−3), n-nonanal (0–500 ng m−3, 89 ng m−3), and n-decanal (0–230 ng m−3, 39 ng m−3). These concentrations are among the highest ever reported in the urban and forest atmosphere. We found that gaseous α-dicarbonyls (glyoxal and methylglyoxal) are more than 20 times more abundant than particulate carbonyls and that glycolaldehyde is one order of magnitude more abundant than in aerosol phase. In contrast, hydroxyacetone and normal aldehydes (nonanal and decanal) are equally present in both phases. Time-resolved variations of carbonyls did not show any a clear diurnal pattern, except for hydroxyacetone. We found that glyoxal, methylglyoxal and glycolaldehyde positively correlated with levoglucosan (a tracer of biomass burning), suggesting that a contribution from field burning of agricultural wastes (wheat crops) is significant for the bifunctional carbonyls in the atmosphere of Mt. Tai. Upward transport of the pollutants to the mountaintop from the low lands in the North China Plain is a major process to control the distributions of carbonyls in the upper atmosphere over Mt. Tai.

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43

Liu, Zeqian, Yang Cui, Qiusheng He, Lili Guo, Xueying Gao, Yanli Feng, Yuhang Wang, and Xinming Wang. "Seasonal Variations of Carbonyls and Their Contributions to the Ozone Formation in Urban Atmosphere of Taiyuan, China." Atmosphere 12, no. 4 (April 17, 2021): 510. http://dx.doi.org/10.3390/atmos12040510.

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Ambient carbonyls are critical precursors of ozone (O3) and secondary organic aerosols (SOA). To better understand the pollution characteristics of carbonyls in Taiyuan, field samplings were conducted, and 13 carbonyls were detected in an urban site of Taiyuan for the four seasons. The total concentration of carbonyls in the atmosphere was 19.67 ± 8.56 μg/m3. Formaldehyde (7.70 ± 4.78 μg/m3), acetaldehyde (2.95 ± 1.20 μg/m3) and acetone (5.57 ± 2.41 μg/m3) were the dominant carbonyl compounds, accounting for more than 85% of the total carbonyls. The highest values for formaldehyde and acetone occurred in summer and autumn, respectively, and the lowest occurred in winter. The variations for acetaldehyde were not distinct in the four seasons. Formaldehyde and acetone levels increased obviously in the daytime and decreased at night, while acetaldehyde did not show significant diurnal variations. Higher temperature and stronger sunlight intensity could facilitate the photochemical reaction of volatile organic compounds (VOCs) and enhance the O3 levels in summer. Formaldehyde and acetaldehyde contributed 70–95% of carbonyls’ ozone formation potential (OFP) caused by carbonyls with the highest totals of 268.62 μg/m3 and 38.14 μg/m3, respectively. The highest concentrations of carbonyls from south and southwest winds in summer suggest that the coke industries in the southern Taiyuan Basin should be, firstly, controlled for the alleviation of ozone pollution.

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44

Das, Aniruddha, Soumen Sarkar, Baitan Chakraborty, Abhishek Kar, and Umasish Jana. "Catalytic Alkyne/Alkene-Carbonyl Metathesis: Towards the Development of Green Organic Synthesis." Current Green Chemistry 7, no. 1 (May 15, 2020): 5–39. http://dx.doi.org/10.2174/2213346106666191105144019.

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The construction of carbon-carbon bond through the metathesis reactions between carbonyls and olefins or alkynes has attracted significant interest in organic chemistry due to its high atomeconomy and efficiency. In this regard, carbonyl–alkyne metathesis is well developed and widely used in organic synthesis for the atom-efficient construction of various carbocycles and heterocycles in the presence of catalytic Lewis acids or Brønsted acids. On the other hand, alkene-carbonyl metathesis is recently developed and has been a topic of great importance in the field of organic chemistry because they possess attractive qualities involving metal-mediated, metal-free intramolecular, photochemical, Lewis acid-mediated ring-closing metathesis, ring-opening metathesis and cross-metathesis. This review covers most of the strategies of carbonyl–alkyne and carbonyl–olefin metathesis reactions in the synthesis of complex molecules, natural products and pharmaceuticals as well as provides an overview of exploration of the metathesis reactions with high atom-economy as well as environmentally and ecologically benign reaction conditions.

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45

Pace, Vittorio, and Wolfgang Holzer. "Chemoselective Activation Strategies of Amidic Carbonyls towards Nucleophilic Reagents." Australian Journal of Chemistry 66, no. 5 (2013): 507. http://dx.doi.org/10.1071/ch13042.

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Important advancements have been made in recent years in the development of chemoselective additions of nucleophiles to well known inert amide carbonyls in the presence of multi-electrophilic substrates. Herein, we present the most relevant results showing how carbonyl amides can be chemoselectively functionalised in the presence of electrophilic functionalities such as Weinreb amides.

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46

Liepa, AJ, AJ Liepa, TC Morton, and TC Morton. "Synthesis of 1-(α-Acyloxy-2-hydroxybenzyl)Azoles and Related Compounds by an Acyl Transfer Reaction." Australian Journal of Chemistry 42, no. 11 (1989): 1961. http://dx.doi.org/10.1071/ch9891961.

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Novel azole adducts were produced by reaction of azoles and 2-acyloxyaryl aldehydes. The mechanism of the reaction involves attack by the azole at the carbonyl group and transfer of the acyl group to form an azole-substituted benzylic ester. 2-Acyloxyaryl ketones did not undergo an analogous reaction. An aminal was formed rather than an azole-substituted benzylic carbonate when a 2-aryl aldehyde carbonate was used as substrate.

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47

Li, Guoliang, Limei Wen, and R. Bruce King. "Heterobimetallic Chromium Manganese Carbonyl Nitrosyls: Comparison with Isoelectronic Homometallic Binuclear Chromium Carbonyl Nitrosyls and Manganese Carbonyls." Inorganics 7, no. 10 (October 21, 2019): 127. http://dx.doi.org/10.3390/inorganics7100127.

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The heterometallic chromium-manganese carbonyl nitrosyls CrMn(NO)(CO)n (n = 9, 8) have been investigated by density functional theory. The lowest energy CrMn(NO)(CO)9 structures have unbridged staggered conformations with a ~2.99 Å Cr–Mn single bond similar to the experimental and lowest energy structures of the isoelectronic Mn2(CO)10 and Cr2(NO)2(CO)8. A significantly higher energy CrMn(NO)(CO)9 isomer has a nearly symmetrical bridging nitrosyl group and a very weakly semibridging carbonyl group. The two lowest energy structures of the unsaturated CrMn(NO)(CO)8 have a five-electron donor bridging η2-µ-NO nitrosyl group or a four-electron donor bridging η2-µ-CO group, as well as a Cr–Mn single bond of length ~2.94 Å. The next higher energy CrMn(NO)(CO)8 structure has exclusively terminal CO and NO ligands and a shorter Cr–Mn single bond of ~2.85 Å, suggesting an 18-electron configuration for the manganese atom and a 16-electron configuration for the chromium atom indicated by a vacant coordination site nearly perpendicular to the Cr–Mn bond.

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48

Bujok, Jolanta, Marlena Gąsior-Głogowska, Michał Marszałek, Natalia Trochanowska-Pauk, František Zigo, Alexander Pavľak, Małgorzata Komorowska, and Tomasz Walski. "Applicability of FTIR-ATR Method to Measure Carbonyls in Blood Plasma after Physical and Mental Stress." BioMed Research International 2019 (March 26, 2019): 1–9. http://dx.doi.org/10.1155/2019/2181370.

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Introduction. Oxidative stress is a state of imbalance between the production of reactive oxygen species and antioxidant defenses. It results in the oxidation of all cellular elements and, to a large extent, proteins, causing inter alia the formation of carbonyl groups in their structures. The study focused on assessment of changes in the plasma protein-bound carbonyls in police horses after combat training and after rest and the applicability of infrared spectroscopy with a Fourier transform, utilizing the attenuated total reflectance (FTIR-ATR) in detecting plasma protein oxidation. Methods. We evaluated the influence of both the different concentrations of hydrogen peroxide and combat training on protein carbonylation in horse blood plasma. The oxidation of plasma proteins was assessed using a spectrophotometric method based on the carbonyl groups derivatization with 2,4-dinitrophenylhydrazine (DNPH). The measured values were correlated with the carbonyl groups concentrations determined by means of the FTIR-ATR method. Results. The linear correlation between the DNPH and FTIR-ATR methods was shown. The concentration of plasma protein-bound carbonyls significantly deceased in police horses after one-day rest when compared to the values measured directly after the combat training (a drop by 23%, p<0.05 and 29%, p<0.01 measured by DNPH and FTIR-ATR methods, respectively). These results were consistent with the proteins phosphorylation analysis. Conclusion. The FTIR-ATR method may be applied to measure the level of plasma proteins peroxidation.

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Hosoya, Akihiro, Tadashi Narita, and Hiroshi Hamana. "Radical Addition of Diethyl Carbonate to Pentafluoropropen-2-yl Benzoate." Collection of Czechoslovak Chemical Communications 73, no. 12 (2008): 1655–62. http://dx.doi.org/10.1135/cccc20081655.

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The reactivity in radical addition of diethyl carbonate to pentafluoropropen-2-yl benzoate [CF2=C(CF3)OCOC6H5] (BPFP) was investigated to afford the one-to-one addition product by the carbon-carbon bond formation in the presence of dibenzoyl peroxide at 80 °C. The reaction took place predominantly on the methylene group of diethyl carbonate. The mechanism of the hydrogen abstraction from diethyl carbonate followed by the addition to BPFP was proposed. This might be the first example that shows an addition of an organic compound bearing carbonyl group to a polyfluorinated vinyl compound. The method may be a facile way to prepare pentafluoroalkyl-substituted organic compounds by the formation of carbon-carbon bonds with the aid of fluorine atoms. The radical addition reaction of dipropyl carbonate, ethyl methyl carbonate, dibenzyl carbonate and ethylene carbonate to BPFP showed no peaks assignable to addition products by the analysis of reaction systems with GC-MS.

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50

Niang-Gaye, P., and N. Karpel van Leitner. "Participation des radicaux carbonate à l’oxydation de l’atrazine lors de l’ozonation de solutions aqueuses contenant des ions hydrogénocarbonate." Revue des sciences de l'eau 18, no. 1 (April 12, 2005): 65–86. http://dx.doi.org/10.7202/705550ar.

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L’étude porte sur la détermination de la contribution des espèces O3, OH° et CO3°- dans la dégradation de l’atrazine lors de l’ozonation de solutions contenant différentes concentrations en ions hydrogénocarbonate et en carbone organique. Le suivi de la concentration en atrazine et en ozone dissous, et les expressions cinétiques ont permis de calculer les concentrations en radicaux hydroxyle et carbonate au cours des réactions. A partir des données expérimentales obtenues sur des eaux pures additionnées de carbone organique et inorganique, les résultats indiquent que l’élimination du micropolluant résulte de l’action de l’ozone (pour une faible part), des radicaux hydroxyle issus de la décomposition de l’ozone, mais aussi pour une part très significative, des radicaux carbonate. La participation des radicaux CO3°- diminue lorsque la concentration en carbone organique augmente. Les radicaux carbonate peuvent être responsable de plus de 40 % de la dégradation de l’atrazine lors de l’ozonation en présence de 7 mM d’ions hydrogénocarbonate et 129 µM d’ions glycolate utilisés comme molécule modèle pour l’apport de carbone organique. Les résultats obtenus sur des eaux naturelles confirment les conclusions déduites des expériences sur des eaux de composition connue.

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Journal articles on the topic 'Carbonyle'

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