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Articles de revues sur le sujet « Cyclopropane »

Auteur : Grafiati

Publié le 4 juin 2021

Mis à jour le 25 juillet 2025

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1

Craig, Alexander J., та Bill C. Hawkins. "The Bonding and Reactivity of α-Carbonyl Cyclopropanes". Synthesis 52, № 01 (2019): 27–39. http://dx.doi.org/10.1055/s-0039-1690695.

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The cyclopropane functionality has been exploited in a myriad of settings that range from total synthesis and methodological chemistry, to medical and materials science. While it has been seen in such a breadth of settings, the typical view of the cyclopropane moiety is that its reactivity is derived primarily from the release of ring strain. While this simplified view is a useful shorthand, it ignores the specific nature of cyclopropyl molecular orbitals. This review aims to present the different facets of cyclopropane bonding by examining the main models that have been used to explain the re

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2

Dent, BR, B. Halton, and AMF Smith. "Synthesis and Trapping of Some Reactive Cyclopropenes." Australian Journal of Chemistry 39, no. 10 (1986): 1621. http://dx.doi.org/10.1071/ch9861621.

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Commencing with 1,1,2-tribromo-2-trimethylsilylcyclopropane (1d), 1,2- dibromo -and 1-bromo-2-trimethylsilyl-cyclopropene (2d) and (6) are easily prepared. These reactive cyclopropenes decompose on standing at ambient temperature but can be trapped in situ as Diels-Alder adducts (4) and (5). Furthermore, 1,2-bis( trimethylsilyl )- and 1- trimethylsilyl-cyclopropene (8) and (9) can be prepared from cyclopropane (1d) via the bromo - and lithio-trimethylsilylcyclopropenes (6) and (7) in a 'one-pot' procedure and trapped as adducts (4e,f) respectively.

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3

Gemoets, J. P., M. Bravo, C. E. McKenna, G. J. Leigh, and B. E. Smith. "Reduction of cyclopropene by NifV- and wild-type nitrogenases from Klebsiella pneumoniae." Biochemical Journal 258, no. 2 (1989): 487–91. http://dx.doi.org/10.1042/bj2580487.

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The nitrogenase from wild-type Klebsiella pneumoniae reduces cyclopropene to cyclopropane and propene in the ratio 1:2 at pH 7.5. We show in this paper that the nitrogenase from a nifV mutant of K. pneumoniae also reduces cyclopropene to cyclopropane and propene, but the ratio of products is now 1:1.4. However, both nitrogenases exhibit the same Km for cyclopropene (2.1 x 10(4) +/- 0.2 x 10(4) Pa), considerably more than the Km for the analogous reaction with Azotobacter vinelandii nitrogenase under the same conditions (5.1 x 10(3) Pa). Analysis of the data shows that the different product rat

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Kohout, Ladislav. "The synthesis of 5,6-cyclopropanocholestanes with oxygen functions in positions 3 and 7." Collection of Czechoslovak Chemical Communications 51, no. 2 (1986): 429–35. http://dx.doi.org/10.1135/cccc19860429.

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The Simmons-Smith methylenation of the double bond in 3β-acetoxycholest-5-en-7-ols takes place selectively under formation of an adduct the configuration of which is determined by the configuration of the 7-hydroxyl group: 7β-alcohol IV gave 5β,6β-cyclopropane derivative VI, 7α-alcohol V gave 5α,6α-cyclopropane derivative VIII. On photochemically initiated cyclization of 3β-acetoxy-B-homo-5-en-7a-one (XIII) we obtained the product with an α-cyclopropane ring exclusively, i.e. 3β-acetoxy-5,6α-cyclopropano-5α-cholestan-7-one (XII).

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Ben Hamadi, Naoufel, and Ahlem Guesmi. "Synthesis of New Spiro-Cyclopropanes Prepared by Non-Stabilized Diazoalkane Exhibiting an Extremely High Insecticidal Activity." Molecules 27, no. 8 (2022): 2470. http://dx.doi.org/10.3390/molecules27082470.

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The synthesis of new insecticidal gem-dimethyspiro-cyclopropanes derived from pyrrolidine-2,3-dione have been described, and their biological effect against different insect species has been evaluated. The presented results demonstrate the excellent insecticidal activity of cyclopropane 5c against Aedes aegypti and Musca domestica. Cyclopropane 5c showed the quickest knockdown and the best killing against Aedes aegypti and Musca domestica compared to trans-chrysanthemic acid and pyrethrin. The biological results of the high insecticidal activity were confirmed by the results of docking. This i

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Singh, Satya Prakash, and Pompozhi Protasis Thankachan. "Hydroboration of Substituted Cyclopropane: A Density Functional Theory Study." Advances in Chemistry 2014 (August 18, 2014): 1–7. http://dx.doi.org/10.1155/2014/427396.

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The hydroboration of substituted cyclopropanes has been investigated using the B3LYP density functional method employing 6-31G** basis set. Borane moiety approaching the cyclopropane ring has been reported. It is shown that the reaction proceeds via a three-centered, “loose” and “tight,” transition states when boron added to the cyclopropane across a bond to a substituents. Single point calculations at higher levels of theory were also performed at the geometries optimized at the B3LYP level, but only slight changes in the barriers were observed. Structural parameters for the transition state

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Trudeau, Stéphane, and Pierre Deslongchamps. "Novel synthesis of a highly functionalized cyclopropane derivative." Canadian Journal of Chemistry 81, no. 9 (2003): 1003–11. http://dx.doi.org/10.1139/v03-119.

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A model study was carried out to explore the feasibility of synthesizing fused tricyclic ring structures containing a C7C8 double bond juncture (steroid numbering) by employing an SN2' cyclization of a silyl enol ether to displace an allylic acetate as the key step. Instead of the anticipated product, highly functionalized cyclopropanes were obtained. These novel cyclopropane structures are the result of the concomitant 1,2-migration of a dithiane thioether moiety and the eventual displacement of the acetate group, followed by the cyclization of the silyl enol ether.Key words: tricycles, SN2'

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Fadeev, Alexander A., Alexey O. Chagarovskiy, Anton S. Makarov, et al. "Synthesis of (Het)aryl 2-(2-hydroxyaryl)cyclopropyl Ketones." Molecules 25, no. 23 (2020): 5748. http://dx.doi.org/10.3390/molecules25235748.

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A simple general method for the synthesis of 1-acyl-2-(ortho-hydroxyaryl)cyclopropanes, which belong to the donor–acceptor cyclopropane family, has been developed. This method, based on the Corey–Chaykovsky cyclopropanation of 2-hydroxychalcones, allows for the preparation of a large diversity of hydroxy-substituted cyclopropanes, which can serve as promising building blocks for the synthesis of various bioactive compounds.

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Ramnauth, Jailall, and Edward Lee-Ruff. "Photodecarbonylation of chiral cyclobutanones." Canadian Journal of Chemistry 75, no. 5 (1997): 518–22. http://dx.doi.org/10.1139/v97-060.

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Triplet photosensitized irradiation of 2(S),3(R)-bis[(benzoyloxy)methyl]cyclobutanone gave optically pure (−)E-1(S),2(S)-bis(benzoyloxymethyl)cyclopropane as a major product in the nonpolar fraction along with its stereoisomer and cycloelimination products. The absolute stereochemistry of the chiral cyclopropane was established by independent synthesis and X-ray crystal structure determination of a synthetic precursor. The distribution of decarbonylation and cycloelimination products was inversely dependent on the concentration of the substrate. Irradiation of the same ketone in tetrahydrofura

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Finta, Zoltán, Zoltán Hell, Agnieszka Cwik, and László Tőke. "A Simple Synthesis of 1,1,2-tris-(Hydroxymethyl)-Cyclopropane and Its Dihalo Derivatives." Journal of Chemical Research 2002, no. 9 (2002): 459–60. http://dx.doi.org/10.3184/030823402103172653.

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The phase transfer catalytic cyclopropanation of the malonic ester of allylic alcohol or its 3,3-dibromo and 3,3-dichloro derivatives yields bicyclic cyclopropane carboxylic acid lactones; reduction of these lactones with LiAlH4 in boiling THF yields the appropriate 1,1,2-tris-(hydroxymethyl)cyclopropanes in satisfactory yield.

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Rademacher, Paul. "Photoelectron Spectra of Cyclopropane and Cyclopropene Compounds." Chemical Reviews 103, no. 4 (2003): 933–76. http://dx.doi.org/10.1021/cr0100143.

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Hassenrück, Jessica, and Valentin Wittmann. "Cyclopropene derivatives of aminosugars for metabolic glycoengineering." Beilstein Journal of Organic Chemistry 15 (March 4, 2019): 584–601. http://dx.doi.org/10.3762/bjoc.15.54.

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Cyclopropenes have been proven valuable chemical reporter groups for metabolic glycoengineering (MGE). They readily react with tetrazines in an inverse electron-demand Diels–Alder (DAinv) reaction, a prime example of a bioorthogonal ligation reaction, allowing their visualization in biological systems. Here, we present a comparative study of six cyclopropene-modified hexosamine derivatives and their suitability for MGE. Three mannosamine derivatives in which the cyclopropene moiety is attached to the sugar by either an amide or a carbamate linkage and that differ by the presence or absence of

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13

Simaan, Marwan, and Ilan Marek. "Diastereo- and enantioselective preparation of cyclopropanol derivatives." Beilstein Journal of Organic Chemistry 15 (March 21, 2019): 752–60. http://dx.doi.org/10.3762/bjoc.15.71.

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The diastereoselective carbocupration reaction of alkoxy-functionalized cyclopropene derivatives, followed by a subsequent trapping of the resulting cyclopropylmetal species with an electrophilic source of oxygen (oxenoid) afforded various tetrasubstituted cyclopropanol derivatives in high diastereo- and enantiomeric ratios. Similarly, the enantioselective copper-catalyzed carbomagnesiation/oxidation (or amination) sequence on achiral nonfunctionalized cyclopropenes provided the desired cyclopropanol (and cyclopropylamine) derivatives in excellent diastereo- and enantiomeric excesses.

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Matyas, Libor, Radek Pohl, and Alexander Kasal. "Neighboring Group Participation in 12,20-Dioxopregnanes." Natural Product Communications 2, no. 11 (2007): 1934578X0700201. http://dx.doi.org/10.1177/1934578x0700201108.

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12,20-Dioxo-5α-pregnan-3β-yl acetate, obtained from hecogenin, was treated with NaH in DMSO to yield the bridged cyclopropano ketone, 3β-hydroxy-12α,21-cyclo-12β,21-methano-5α,17α-pregnan-20-one. In tert-BuOH the reaction leads to 3β-hydroxy-12,21-cyclo-5α-pregn-12,21-en-20-one. Experimental data prove that the new methylene group of the cyclopropane ring came from DMSO.

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15

Song, Xixi, Junbiao Chang, Yuanyuan Zhu, Shuang Zhao, and Minli Zhang. "Diastereoselective Synthesis of Spirobarbiturate-Cyclopropanes through Organobase-Mediated Spirocyclopropanation of Barbiturate-Based Olefins with Benzyl Chlorides." Synthesis 51, no. 04 (2018): 899–906. http://dx.doi.org/10.1055/s-0037-1609637.

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The organobase-mediated diastereoselective spirocyclopropanation of barbiturate-based olefins with 2,4-disubstituted benzyl chlorides has been developed. The reactions were carried out efficiently to afford the desired spirobarbiturate-cyclopropanes in up to 95% yield with more than 20:1 dr in favor of anti-isomers. In order to extend synthetic utility of the spiro-products, a Lewis acid induced cyclopropane-ring-expansion isomerization was also demonstrated.

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Aleksandrova, Anastasiia M., Alona S. Cherednichenko, and Yuliya V. Rassukana. "The Synthesis of Functionalized Dimethylphosphinoyl Cyclopropanes and Cyclobutanes." Journal of Organic and Pharmaceutical Chemistry 21, no. 4 (2023): 36–42. http://dx.doi.org/10.24959/ophcj.23.299237.

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A simple preparative approach to a series of functionalized dimethylphosphinoyl-containing cyclopropanes and cyclobutanes has been developed; it is based on cyclocondensation of dimethylphosphinoyl acetonitrile with 1,2- and 1,3-dibromoalkanes. Synthetic procedures for obtaining nitriles, amines and carboxylic acids containing in their structure small saturated cyclic rings of cyclopropane or cyclobutane and a dimethylphosphine oxide fragment, which are popular in drug design, have been developed.

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17

Wanapun, D., K. A. Van Gorp, N. J. Mosey, M. A. Kerr, and T. K. Woo. "The mechanism of 1,3-dipolar cycloaddition reactions of cyclopropanes and nitrones A theoretical study." Canadian Journal of Chemistry 83, no. 10 (2005): 1752–67. http://dx.doi.org/10.1139/v05-182.

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The 1,3-dipolar cycloaddition reaction of cyclopropanes and nitrones to give tetrahydro-1,2-oxazine has been studied with density functional theory calculations at the B3LYP/6-31+G(d,p) level of theory. Realistic substituents were modelled including those at the 2-, 3-, 4-, and 6-positions of the final oxazine ring product. The strained σ bond of the cyclopropane was found to play the role of an alkene in a conventional [3+2] dipolar cycloaddition. Two distinct, but similar, reaction mechanisms were found an asymmetric concerted pathway and a stepwise zwitterionic pathway. The reaction barri

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Miranda, Margarida S., Darío J. R. Duarte, Joaquim C. G. Esteves da Silva, and Joel F. Liebman. "Protonated heterocyclic derivatives of cyclopropane and cyclopropanone: classical species, alternate sites, and ring fragmentation." Canadian Journal of Chemistry 93, no. 7 (2015): 708–14. http://dx.doi.org/10.1139/cjc-2015-0029.

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A computational study has been performed for protonated oxygen- or nitrogen-containing heterocyclic derivatives of cyclopropane and cyclopropanone. We have searched for the most stable conformations of the protonated species using density functional theory with the B3LYP functional and the 6-31G(2df,p) basis set. More accurate enthalpy values were obtained from G4 calculations. Proton affinities and gas-phase basicities were accordingly derived.

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Babu, Kaki Raveendra, Xin He, and Silong Xu. "Lewis Base Catalysis Based on Homoconjugate Addition: Rearrangement of Electron-Deficient Cyclopropanes and Their Derivatives." Synlett 31, no. 02 (2019): 117–24. http://dx.doi.org/10.1055/s-0039-1690753.

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Cyclopropane is one of the most reactive functionalities owing to its intrinsic ring strain. Transition-metal catalysis and Lewis acid catalysis have been extensively used in ring openings of cyclopropanes; however, Lewis base-catalyzed activation of cyclopropanes remains largely unexplored. Upon nucleophilic attack with Lewis bases, cyclopropanes undergo ring cleavage in a manner known as homoconjugate addition to form zwitterionic intermediates, which have significant potential for reaction development but have garnered little attention. Here, we present a brief overview of this area, with a

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Mlostoń, Grzegorz, Mateusz Kowalczyk, André U. Augustin, Peter G. Jones, and Daniel B. Werz. "Ferrocenyl-substituted tetrahydrothiophenes via formal [3 + 2]-cycloaddition reactions of ferrocenyl thioketones with donor–acceptor cyclopropanes." Beilstein Journal of Organic Chemistry 16 (June 10, 2020): 1288–95. http://dx.doi.org/10.3762/bjoc.16.109.

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Ferrocenyl thioketones reacted with donor–acceptor cyclopropanes in dichloromethane at room temperature in the presence of catalytic amounts of Sc(OTf)3 yielding tetrahydrothiophene derivatives, products of formal [3 + 2]-cycloaddition reactions, in moderate to high yields. In all studied cases, dimethyl 2-arylcyclopropane dicarboxylates reacted with the corresponding aryl ferrocenyl thioketones in a completely diastereoselective manner to form single products in which (C-2)-Ar and (C-5)-ferrocenyl groups were oriented in a cis-fashion. In contrast, the same cyclopropanes underwent reaction wi

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Ledingham, Edward, Christopher Merritt, Christopher Sumby, Michelle Taylor, and Ben Greatrex. "Stereoselective Cyclopropanation of (–)-Levoglucosenone Derivatives Using Sulfonium and Sulfoxonium Ylides." Synthesis 49, no. 12 (2017): 2652–62. http://dx.doi.org/10.1055/s-0036-1588971.

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The synthesis of tri- and tetrasubstituted cyclopropanes from 3-aryl-substituted levoglucosenones (LGO) has been developed. In contrast to the unstabilised ylide dimethylsulfonium methylide which gives epoxides from LGO via 1,2-addition, we have found that the soft nucleophile dimethylsulfoxonium methylide affords cyclopropanes in moderate yields from LGO and in excellent yields and stereoselectivity with 3-aryl LGO derivatives. The use of 1,1,3,3-tetramethylguanidine as base in DMSO to generate the ylide provided the best yields and shortest reaction times. Ester stabilised sulfonium ylides c

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Ivanova, Olga, Vladimir Andronov, Irina Levina, Alexey Chagarovskiy, Leonid Voskressensky, and Igor Trushkov. "Convenient Synthesis of Functionalized Cyclopropa[c]coumarin-1a-carboxylates." Molecules 24, no. 1 (2018): 57. http://dx.doi.org/10.3390/molecules24010057.

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A simple method has been developed for the synthesis of cyclopropa[c]coumarins, which belong to the donor-acceptor cyclopropane family and, therefore, are promising substrates for the preparation of chromene-based fine chemicals. The method, based on the acetic acid-induced intramolecular transesterification of 2-arylcyclopropane-1,1-dicarboxylates, was found to be efficient for substrates containing hydroxy group directly attached to the aromatic ring.

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Vereshchagin, Anatolii N., Michail N. Elinson, Nikita O. Stepanov, and Gennady I. Nikishin. "New Way to Substitute Tetracyanocyclopropanes: One-Pot Cascade Assembling of Carbonyls and Malononitrile by the Only Bromine Direct Action." ISRN Organic Chemistry 2011 (July 26, 2011): 1–5. http://dx.doi.org/10.5402/2011/469453.

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The new type of the chemical cascade reaction was found: formation of cyclopropanes from carbonyl compounds and CH acid by the only bromine direct action. The action of aqueous bromine on the carbonyl compounds and malononitrile in EtOH-H2O solutions in the presence of NaOAc results in the formation of 3-substituted 1,1,2,2-tetracyanocyclopropanes in 48–93% yields. The latter are well-known precursors for the different bicyclic heterosystems, among them those containing cyclopropane ring and those possessing different types of pharmacological activity.

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Fang, Zeguo, Nawaf Al-Maharik, Peer Kirsch, Matthias Bremer, Alexandra M. Z. Slawin, and David O’Hagan. "Synthesis of organic liquid crystals containing selectively fluorinated cyclopropanes." Beilstein Journal of Organic Chemistry 16 (April 14, 2020): 674–80. http://dx.doi.org/10.3762/bjoc.16.65.

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This paper describes the synthesis of a series of organic liquid crystals (LCs) containing selectively fluorinated cyclopropanes at their termini. The syntheses used difluorocarbene additions to olefin precursors, an approach which proved straightforward such that these liquid crystal candidates could be efficiently prepared. Their physical and thermodynamic properties were evaluated and depending on individual structures, they either displayed positive or negative dielectric anisotropy. The study gives some guidance into effective structure–property relationships for the design of LCs contain

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Zhang, Junliang, and Yuanjing Xiao. "ChemInform Abstract: Cyclization of Cyclopropane- or Cyclopropene-Containing Compounds." ChemInform 41, no. 38 (2010): no. http://dx.doi.org/10.1002/chin.201038242.

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Denson, J. S. "Cyclopropane." International Anesthesiology Clinics 36, no. 4 (1998): 61–82. http://dx.doi.org/10.1097/00004311-199803640-00008.

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Lamberty, J. M. "Cyclopropane." Anaesthesia 42, no. 2 (1987): 212–13. http://dx.doi.org/10.1111/j.1365-2044.1987.tb03011.x.

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Ball, C., and R. N. Westhorpe. "Cyclopropane." Anaesthesia and Intensive Care 34, no. 6 (2006): 701. http://dx.doi.org/10.1177/0310057x0603400621.

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Mato, Mauro, Inmaculada Martín-Torres, Bart Herlé, and Antonio M. Echavarren. "Cyclopropane–alkene metathesis by gold(i)-catalyzed decarbenation of persistent cyclopropanes." Organic & Biomolecular Chemistry 17, no. 17 (2019): 4216–19. http://dx.doi.org/10.1039/c9ob00359b.

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Boichenko, Maksim A., Andrey Yu Plodukhin, Vitaly V. Shorokhov, et al. "Synthesis of 1,5-Substituted Pyrrolidin-2-ones from Donor–Acceptor Cyclopropanes and Anilines/Benzylamines." Molecules 27, no. 23 (2022): 8468. http://dx.doi.org/10.3390/molecules27238468.

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We developed a straightforward synthetic route to pharmacologically important 1,5-substituted pyrrolidin-2-ones from donor–acceptor cyclopropanes bearing an ester group as one of the acceptor substituents. This method includes a Lewis acid-catalyzed opening of the donor–acceptor cyclopropane with primary amines (anilines, benzylamines, etc.) to γ-amino esters, followed by in situ lactamization and dealkoxycarbonylation. The reaction has a broad scope of applicability; a variety of substituted anilines, benzylamines, and other primary amines as well as a wide range of donor–acceptor cyclopropan

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Gavrus, Delia. "Envisioning Cyclopropane: Scientific Product or Medical Technology?" Scientia Canadensis 33, no. 1 (2011): 3–28. http://dx.doi.org/10.7202/1000843ar.

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In the late 1920s, V.E. Henderson and his team at the University of Toronto discovered the anaesthetic properties of cyclopropane. For a number of reasons, Henderson did not envision cyclopropane as a useful technology: to him it was simply a gas that possessed anaesthetic properties, rather than a potential clinical product, and this explains why cyclopropane was not first introduced into Toronto hospitals. In contrast, the practicing anaesthesiologist Ralph M. Waters envisioned cyclopropane as a medical technology, partly because it could assist his effort to professionalize anaesthesiology

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Don Lawson, Chioma, Max Maza-Iglesias, Muthana Sirhan, Jumaa Al Dulayymi та Mark Baird. "The Synthesis of Single Enantiomers of α-Mycolic Acids of Mycobacterium tuberculosis and Related Organisms, with Alternative Cyclopropane Stereochemistries". SynOpen 01, № 01 (2017): 0103–16. http://dx.doi.org/10.1055/s-0036-1588556.

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We report the synthesis of three stereoisomers of a mycolic acid from Mycobacterium tuberculosis containing a di-cis-cyclopropane and of two stereoisomers of a mycolic acid containing a proximal trans-cyclopropane and a distal cis-cyclopropane.

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Mead, Keith, and Yahaira Reyes. "Acetoxy-Substituted Cyclopropane Dicarbonyls as Stable Donor–Acceptor–Acceptor Cyclopropanes." Synthesis 47, no. 19 (2015): 3020–26. http://dx.doi.org/10.1055/s-0034-1379934.

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Ben Hamadi, Naoufel, Ahlem Guesmi, and Wided Nouira. "Asymmetric one-pot synthesis of cyclopropanes." Macedonian Journal of Chemistry and Chemical Engineering 35, no. 1 (2016): 45. http://dx.doi.org/10.20450/mjcce.2016.835.

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Cycloaddition of the diazoalkanes to electron-deficient olefins (in situ) affords polysubstituted cyclopropanes in high yields (up to 85%). Deprotection of the ketal protecting group provided water-soluble cyclopropane-bearing carbohydrate in good yields. Antimicrobial activity screening of the synthesized compounds 8 and 9, utilizing a variety of Gram-positive (Staphylococcus aureus and Enterococcus fecalis), Gram-negative bacteria (Escherichia coli and Klebsiella pneumoniae) and yeast (Candida albicans), exhibited that all the prepared analogues acquire promising activities against both Gram

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Herraiz, Ana G., and Marcos G. Suero. "New Alkene Cyclopropanation Reactions Enabled by Photoredox Catalysis via Radical Carbenoids." Synthesis 51, no. 14 (2019): 2821–28. http://dx.doi.org/10.1055/s-0037-1611872.

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We describe the recent emergence of a new approach for the synthesis of cyclopropane rings by means of photoredox catalysis. This methodology relies on the photocatalytic generation of radical carbenoids or carbenoid-like radicals as cyclopropanating species, and is characterized by excellent functional group tolerance, chemoselectivity and the ability to form cyclopropanes with excellent control from E/Z alkene mixtures. The mild reaction conditions and employment of user-friendly reagents are highly attractive features that may lead to this approach being used in academic and industrial labo

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Altamore, Timothy M., Oanh T. K. Nguyen, Quentin I. Churches, et al. "Concise Synthesis of Enantiomerically Pure (1'S,2'R)- and (1'R,2'S)-2S-Amino-3-(2'-aminomethyl-cyclopropyl)propionic Acid: Two E-Diastereoisomers of 4,5-Methano-L-lysine." Australian Journal of Chemistry 66, no. 9 (2013): 1105. http://dx.doi.org/10.1071/ch13309.

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A concise synthesis of both E-isomers of 2S-amino-3-(2′-aminomethyl-cyclopropyl)propionic acid, new methano-l-lysines, is described. The synthetic route includes nine steps from l-methionine, with a key step involving the cyclopropanation of an intermediate E-allylic alcohol. The resultant hydroxymethylcyclopropanes were readily separated and converted into the title α-amino acids. The stereochemistry around the cyclopropane rings was deduced by conducting the cyclopropanation in the presence of N,N,N′,N′-tetramethyl-d-tartaric acid diamide butylboronate, a chiral controller which is known to

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Bilera, Igor V. "The Formation of Small Amounts of Cyclopropane during Pulsed Pyrolysis of C4–C5 Acyclic Alkanes in the Adiabatic Compression Reactor." Reactions 4, no. 3 (2023): 381–97. http://dx.doi.org/10.3390/reactions4030023.

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During high-temperature pulse pyrolysis of acyclic butanes and pentanes under adiabatic compression conditions, cyclopropane, a stressed cyclic hydrocarbon, was found among the reaction products in small quantities for the first time. The analysis of the reaction products was performed by gas chromatography using three capillary columns of different polarity, selectivity and sufficient efficiency. The identification of reaction products, including cyclopropane, was performed using retention times of individual substances and model mixtures, as well as comparing chromatograms with reference chr

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Zhuo, Chun-Xiang, and Jia-Le Wang. "Catalytic Deoxygenative Cyclopropanation of 1,2-Dicarbonyl or Monocarbonyl Compounds via Molybdenum Catalysis." Synlett 33, no. 07 (2021): 599–608. http://dx.doi.org/10.1055/a-1696-4553.

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AbstractThe cyclopropanation of alkenes through the transition-metal-catalyzed decomposition of diazo compounds is a powerful and straightforward strategy to produce cyclopropanes. Nevertheless, the appeal of further application of this strategy is tempered by the potentially explosive nature of the diazo substrates. Therefore, it is highly desirable to develop sustainable and operationally safe surrogates for diazo compounds. In this Synpacts article, we discuss recent advances on the cyclopropane syntheses through the catalytic cyclopropanation of alkenes and metal carbenes generated in situ

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Hara, Koji, Edmond I. Eger, Michael J. Laster, and R. Adron Harris. "Nonhalogenated Alkanes Cyclopropane and Butane Affect Neurotransmitter-gated Ion Channel and G-protein–coupled Receptors." Anesthesiology 97, no. 6 (2002): 1512–20. http://dx.doi.org/10.1097/00000542-200212000-00025.

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Background Anesthetic mechanisms of nonhalogenated alkanes cyclopropane and butane are not understood. This study was designed to look at which neurotransmitter receptors are possible targets for these anesthetics. Methods Effects of cyclopropane and butane on eight recombinant receptors expressed in Xenopus oocytes were examined electrophysiologically. To address molecular mechanisms of interaction with glycine and gamma-aminobutyric acid type A (GABA(A)) receptors, cyclopropane was further tested on alpha1(S267C) glycine receptor and alpha2(S270X)beta1 GABA(A) receptors that were mutated to

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Luo, Hui-Xin, You-Hong Niu, Xiao-Ping Cao, and Xin-Shan Ye. "Cyclopropenes for the Synthesis of Cyclopropane-Fused Dihydroquinolines and Benzazepines." Advanced Synthesis & Catalysis 357, no. 13 (2015): 2893–902. http://dx.doi.org/10.1002/adsc.201500203.

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Liu, Yu, Qiao-Lin Wang, Zan Chen, et al. "Oxidative radical ring-opening/cyclization of cyclopropane derivatives." Beilstein Journal of Organic Chemistry 15 (January 28, 2019): 256–78. http://dx.doi.org/10.3762/bjoc.15.23.

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The ring-opening/cyclization of cyclopropane derivatives has drawn great attention in the past several decades. In this review, recent efforts in the development of oxidative radical ring-opening/cyclization of cyclopropane derivatives, including methylenecyclopropanes, cyclopropyl olefins and cyclopropanols, are described. We hope this review will be of sufficient interest for the scientific community to further advance the application of oxidative radical strategies in the ring-opening/cyclization of cyclopropane derivatives.

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Sathishkannan, Gopal, V. John Tamilarasan, and Kannupal Srinivasan. "Nucleophilic ring-opening reactions of trans-2-aroyl-3-aryl-cyclopropane-1,1-dicarboxylates with hydrazines." Organic & Biomolecular Chemistry 15, no. 6 (2017): 1400–1406. http://dx.doi.org/10.1039/c6ob02552h.

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trans-2-Aroyl-3-aryl-cyclopropane-1,1-dicarboxylates gave dihydropyrazoles when treated with arylhydrazines in refluxing EtOH, whereas they afforded cyclopropane-fused pyridazinones upon treatment with hydrazines in refluxing AcOH.

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Barkan, Daniel, Vivek Rao, George D. Sukenick, and Michael S. Glickman. "Redundant Function of cmaA2 and mmaA2 in Mycobacterium tuberculosis cis Cyclopropanation of Oxygenated Mycolates." Journal of Bacteriology 192, no. 14 (2010): 3661–68. http://dx.doi.org/10.1128/jb.00312-10.

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ABSTRACT The Mycobacterium tuberculosis cell envelope contains a wide variety of lipids and glycolipids, including mycolic acids, long-chain branched fatty acids that are decorated by cyclopropane rings. Genetic analysis of the mycolate methyltransferase family has been a powerful approach to assign functions to each of these enzymes but has failed to reveal the origin of cis cyclopropanation of the oxygenated mycolates. Here we examine potential redundancy between mycolic acid methyltransferases by generating and analyzing M. tuberculosis strains lacking mmaA2 and cmaA2, mmaA2 and cmaA1, or m

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Freedman, Teresa B., Diane L. Hausch, Steven J. Cianciosi, and John E. Baldwin. "Kinetics of thermal racemization of (2S,3S)-1-13C-1,2,3-d3-cyclopropane followed by vibrational circular dichroism spectroscopy." Canadian Journal of Chemistry 76, no. 6 (1998): 806–10. http://dx.doi.org/10.1139/v98-070.

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Vibrational circular dichoism spectra recorded for (2S,3S)-1-13C-1,2,3-d3-cyclopropane and for mixtures of it and the three related stereoisomers prepared through gas-phase thermal stereomutation reactions at 407°C lead to the rate constant for racemization: kα = (4k1 + 4k12) = (3.12 ± 0.04) x 10-5 s-1. This and the rate constant measured for geometrical equilibration between the two chiral and the two achiral stereoisomers of 1-13C-1,2,3-d3-cyclopropane, ki = (8k1 + 4k12) = (4.63 ± 0.20) x 10-5 s-1, give two equations in two unknowns, and allow one to solve for one-center (k1) and two-center

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Jalkanen, K. J., J. D. Gale, G. J. Jalkanen, D. F. McIntosh, A. A. El-Azhary, and G. M. Jensen. "trans-1,2-Dicyano-cyclopropane and other cyano-cyclopropane derivatives." Theoretical Chemistry Accounts 119, no. 1-3 (2007): 211–29. http://dx.doi.org/10.1007/s00214-007-0391-6.

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Wang, Lizhong, Zhenjie Su, Siran Qian, Weijian Ye, and Cunde Wang. "Efficient Preparation of 2,3-Disubstituted Cyclopropane-1-Carbonitriles via Selective Decarboxylation of 1-Cyanocyclopropane-1-Carboxylates." Journal of Chemical Research 41, no. 11 (2017): 636–40. http://dx.doi.org/10.3184/174751917x15094552081161.

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2,3-Disubstituted cyclopropane-1-carbonitriles were efficiently formed via a selective decarboxylation reaction of substituted 2-aroyl-3-aryl-1-cyano-cyclopropane-1-carboxylates in up to 92% yield. The structures of three typical compounds were confirmed by X-ray crystallography.

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Sedenkova, Kseniya N., Kristian S. Andriasov, Tamara S. Kuznetsova, and Elena B. Averina. "Oxyfunctionalization of CH2-Group Activated by Adjacent Three-Membered Ring." Current Organic Synthesis 15, no. 4 (2018): 515–32. http://dx.doi.org/10.2174/1570179415666180405113158.

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Background: Increasing use of the three-membered ring in drug development initiates the search for efficient methods of transformations of cyclopropane derivatives. Oxidation of methylene group activated by an adjacent cyclopropane represents a direct approach towards carbonylcyclopropanes, allows avoiding unnecessary synthetic stages and meets the requirements of atom economy. Objective: In this review all available data concerning the oxidation of cyclopropane-containing hydrocarbons and their functionally substituted derivatives are systematized, and the general regularities between the str

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Corfield, Peter W. R., and Richard A. Kershaw. "Crystal structures of two bicyclo[5.1.0]octanes: potassiumtrans-bicyclo[5.1.0]octane-4-carboxylate monohydrate andcis-bicyclo[5.1.0]octan-4-yl 4-bromobenzenesulfonate." Acta Crystallographica Section E Crystallographic Communications 73, no. 9 (2017): 1357–62. http://dx.doi.org/10.1107/s2056989017011756.

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The crystal structures of thetrans-fused compound potassiumtrans-bicyclo[5.1.0]octane-4-carboxylate monohydrate, K+·C9H13O2−·H2O, (I), and ofcis-bicyclo[5.1.0]octan-4-yl 4-bromobenzenesulfonate, C14H17BrO3S, (II), have been determined. Compound (I) represents the smallesttrans-fused cyclopropane structure known to date, and features the expectedshorteningof the bridging C—C bond relative to the other cyclopropane bond lengths, in contrast to thecis-fused system, (II), where all of the cyclopropane bond lengths are the same. The bicyclic ring system of (I) is disordered across a crystallographi

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Budynina, Ekaterina, Konstantin Ivanov, Ivan Sorokin, and Mikhail Melnikov. "Ring Opening of Donor–Acceptor Cyclopropanes with N-Nucleophiles." Synthesis 49, no. 14 (2017): 3035–68. http://dx.doi.org/10.1055/s-0036-1589021.

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Ring opening of donor–acceptor cyclopropanes with various N-nucleophiles provides a simple approach to 1,3-functionalized compounds that are useful building blocks in organic synthesis, especially in assembling various N-heterocycles, including natural products. In this review, ring-opening reactions of donor–acceptor cyclopropanes with amines, amides, hydrazines, N-heterocycles, nitriles, and the azide ion are summarized.1 Introduction2 Ring Opening with Amines3 Ring Opening with Amines Accompanied by Secondary Processes Involving the N-Center3.1 Reactions of Cyclopropane-1,1-diesters with Pr

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Xie, Yaoming, and Henry F. Schaefer. "Aluminirene (HAlC2H2) and aluminirane (HAlC2H4): aluminum-substituted counterparts of cyclopropene and cyclopropane." Journal of the American Chemical Society 112, no. 14 (1990): 5393–400. http://dx.doi.org/10.1021/ja00170a001.

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