Log in

Relevant bibliographies by topics / Secondary P-deuterium isotope effects / Journal articles

To see the other types of publications on this topic, follow the link: Secondary P-deuterium isotope effects.

Journal articles on the topic 'Secondary P-deuterium isotope effects'

Author: Grafiati

Published: 5 June 2025

Last updated: 1 August 2025

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'Secondary P-deuterium isotope effects.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Koerner, Terry, Kenneth Charles Westaway, Raymond A. Poirier та Y. Wang. "An unusually large secondary α-deuterium kinetic isotope effect in hydride ion SN2 reactions". Canadian Journal of Chemistry 78, № 8 (2000): 1067–72. http://dx.doi.org/10.1139/v00-100.

Full text

Abstract:

Theoretical calculations at the HF/6-31+G* level suggest the secondary α-deuterium kinetic isotope effects for hydride ion SN2 reactions are much larger than expected for the structure of the transition state. The secondary α-deuterium kinetic isotope effects for the SN2 reactions between sodium borohydride (hydride ion) and para-methyl- and para-chlorobenzyl chlorides are much larger than expected as the theoretical calculations suggest. It appears the secondary α-deuterium isotope effects are larger than expected for the structure of the SN2 transition state because the hydride ion is too sm

APA, Harvard, Vancouver, ISO, and other styles

2

Choi, Hyung Soo, and Robert L. Kuczkowski. "Ozonolysis of styrene and p-nitrostyrene. Secondary deuterium isotope effects." Journal of Organic Chemistry 50, no. 6 (1985): 901–2. http://dx.doi.org/10.1021/jo00206a042.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Smith, Peter James, David AJ Crowe, and Kenneth Charles Westaway. "Using secondary alpha deuterium kinetic isotope effects to determine the stereochemistry of an E2 reaction; the stereochemistry of the E2 reaction of 1-chloro-2-phenylethane with potassium tert-butoxide in tert-butyl alcohol." Canadian Journal of Chemistry 79, no. 7 (2001): 1145–52. http://dx.doi.org/10.1139/v01-086.

Full text

Abstract:

Isotopic labelling studies have shown that the E2 reaction of 1-chloro-2-phenylethane with potassium tert-butoxide in tert-butyl alcohol occurs via an anti-periplanar stereochemistry. This demonstrates that the different secondary alpha deuterium kinetic isotope effects found for the high and low base concentrations and in the presence of 18-crown-6 ether are because of changes in transition state structure that occur when the form of the reacting base changes rather than to a change in the stereochemistry of the reaction.Key words: E2 reaction, stereochemistry, secondary alpha deuterium kinet

APA, Harvard, Vancouver, ISO, and other styles

4

Alston, William C., Kari Haley, Ryszard Kanski, Christopher J. Murray, and Julianto Pranata. "Secondary Deuterium Isotope Effects for Enolization Reactions." Journal of the American Chemical Society 118, no. 28 (1996): 6562–69. http://dx.doi.org/10.1021/ja942053k.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Pham, T. V., and K. C. Westaway. "Solvent effects on nucleophilic substitution reactions. III. The effect of adding an inert salt on the structure of the SN2 transition state." Canadian Journal of Chemistry 74, no. 12 (1996): 2528–30. http://dx.doi.org/10.1139/v96-283.

Full text

Abstract:

The nitrogen and secondary α-hydrogen–deuterium kinetic isotope effects found for the SN2 reaction between thiophenoxide ion and benzyldimethylphenylammonium ion at different ionic strengths in DMF at 0 °C indicate that the structure of the transition state changes markedly with the ionic strength of the reaction mixture. In fact, a more reactant-like, more ionic, transition state is found at the higher ionic strength. This presumably occurs because a more ionic transition state is more stable in the more ionic solvent. Key words: transition state, ionic strength, secondary α deuterium kinetic

APA, Harvard, Vancouver, ISO, and other styles

6

Fang, Yao-Ren, and Kenneth Charles Westaway. "Isotope effects in nucleophilic substitution reactions. VIII. The effect of the form of the reacting nucleophile on the transition state structure of an SN2 reaction." Canadian Journal of Chemistry 69, no. 6 (1991): 1017–21. http://dx.doi.org/10.1139/v91-149.

Full text

Abstract:

A spectroscopic investigation indicated that lithium thiophenoxide exists as a contact ion pair complex in dry diglyme whereas the other alkali metal thiophenoxides exist as a solvent-separated ion pair complex in diglyme. The addition of small amounts of water converts the lithium thiophenoxide contact ion pair complex into a solvent-separated ion pair complex. A smaller secondary α-deuterium kinetic isotope effect and a larger Hammett p value are observed when the nucleophile is the contact ion pair complex in the SN2 reaction between n-butyl chloride and thiophenoxide ion in diglyme. This i

APA, Harvard, Vancouver, ISO, and other styles

7

K., Ranganayakulu, and Y. S. Murthy N. "Solvolytic studies in cycloalkyl systems." Journal of Indian Chemical Society Vol. 88, Feb 2011 (2011): 307–13. https://doi.org/10.5281/zenodo.5773579.

Full text

Abstract:

Professor (Retd.), Department of Chemistry, National Institute of Technology, Warangal-506 004, Andhra Pradesh, India Department of Chemistry, Malia Reddy Engineering College, Secunderabad-500 014, Andhra Pradesh, India <em>E-mail</em> : nysrim@yahoo.co.in <em>Manuscript received 14 May 2009, accepted 15 September 2009</em> The angular dependence of the C-H/C-D bond for a stabilization of the developing carbonium ion in the transition state of the solvolysis reaction of cycloalkyl halides has been investigated. This has been achieved by studying the rate of solvolysis of eight cyclic β-de

APA, Harvard, Vancouver, ISO, and other styles

8

Smith, Peter James, та Kenneth Charles Westaway. "Secondary α hydrogen–deuterium kinetic isotope effects in the syn-elimination reaction of 2-phenylethyldimethylamine oxide". Canadian Journal of Chemistry 65, № 9 (1987): 2149–53. http://dx.doi.org/10.1139/v87-359.

Full text

Abstract:

The secondary α-deuterium kinetic isotope effect has been measured for the thermal reaction of 2-phenylethyldimethylamine oxide in 90 mol% DMSO–H2O at 60.0 °C. A large secondary α-deuterium isotope effect of 1.158 per α-D was found, which indicates significant [Formula: see text] bond rupture and very little double bond formation at the transition state for this concerted syn-elimination process. The observed large normal value for (kH/kD)α is discussed in terms of the use of secondary α-D isotope effects for the determination of stereochemistry for a concerted elimination process. Various iso

APA, Harvard, Vancouver, ISO, and other styles

9

Westaway, Kenneth Charles, and Zhu-Gen Lai. "Isotope effects in nucleophilic substitution reactions. VI. The effect of ion pairing on the transition state structure of SN2 reactions." Canadian Journal of Chemistry 66, no. 5 (1988): 1263–71. http://dx.doi.org/10.1139/v88-205.

Full text

Abstract:

Spectroscopic and conductivity studies of sodium thiophenoxide solutions in four different solvents and the secondary α-deuterium kinetic isotope effects found in the presence of 15-crown-5 ether demonstrate that the secondary α-deuterium kinetic isotope effect and transition state structure for the SN2 reaction between sodium thiophenoxide and n-butyl chloride are significantly different, depending on whether the ionic reactant is a solvent-separated ion-pair complex or a free ion. In all three solvents in which the form of the ionic reactant changes, a smaller isotope effect and tighter tran

APA, Harvard, Vancouver, ISO, and other styles

10

Wasylishen, Roderick E., and Neil Burford. "The influence of charge on nuclear magnetic resonance isotope effects." Canadian Journal of Chemistry 65, no. 12 (1987): 2707–12. http://dx.doi.org/10.1139/v87-449.

Full text

Abstract:

Deuterium isotope effects on the 31P shielding constants and spin–spin coupling constants in the isoelectronic series, PH2−, PH3, PH4+, are examined. Also, deuterium isotope effects on the nuclear magnetic resonance parameters of SnH3− are examined and compared with our earlier results on SnH4 and SnH3+. The experimental results are analyzed using the models of Jameson and Osten. In each isoelectronic series it is found that the isotope effects on the heavy atom chemical shifts are largest for the negatively charged ions and essentially zero for the positively charged ions, as predicted by rec

APA, Harvard, Vancouver, ISO, and other styles

11

Shiner, V. J., Henry R. Mahler, R. H. Baker, and R. R. Hiatt. "SECONDARY DEUTERIUM ISOTOPE EFFECTS IN CHEMICAL AND BIOCHEMICAL REACTIONS*." Annals of the New York Academy of Sciences 84, no. 16 (2006): 583–95. http://dx.doi.org/10.1111/j.1749-6632.1960.tb39091.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

Romero, Jonathan, Andrés Reyes, and Julien Wist. "Secondary deuterium isotope effects on the acidity of glycine." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 77, no. 4 (2010): 845–48. http://dx.doi.org/10.1016/j.saa.2010.08.016.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Away, Kenneth Charles West, and Zhu-Gen Lai. "Solvent effects on SN2 transition state structure. II: The effect of ion pairing on the solvent effect on transition state structure." Canadian Journal of Chemistry 67, no. 2 (1989): 345–49. http://dx.doi.org/10.1139/v89-056.

Full text

Abstract:

Identical secondary α-deuterium kinetic isotope effects (transition state structures) in the SN2 reaction between n-butyl chloride and a free thiophenoxide ion in aprotic and protic solvents confirm the validity of the Solvation Rule for SN2 Reactions. These isotope effects also suggest that hydrogen bonding from the solvent to the developing chloride ion in the SN2 transition state does not have a marked effect on the magnitude of the chlorine (leaving group) kinetic isotope effects. Unlike the free ion reactions, the secondary α-deuterium kinetic isotope effect (transition state structure) f

APA, Harvard, Vancouver, ISO, and other styles

14

Wasylishen, Roderick E., and Jan O. Friedrich. "Deuterium isotope effects on nuclear shielding constants and spin–spin coupling constants in the ammonium ion, ammonia, and water." Canadian Journal of Chemistry 65, no. 9 (1987): 2238–43. http://dx.doi.org/10.1139/v87-373.

Full text

Abstract:

Deuterium isotope effects on 15N chemical shifts have been investigated for the ammonium ion, ammonia, and aniline; 1Δ15N(2/1H) equals −293.3, −622.9, and −714.6 ppb respectively. Deviations from additivity are noted for NH4−nDn+ and NH3−nDn; these deviations follow the predictions of Jameson and Osten. For ammonia, examination of the proton nuclear magnetic resonance spectrum yields 1Δ1H(15/14N) = −2.0 ± 0.4 ppb and [Formula: see text]. An accurate value of −1545 ± 5 ppb was obtained for 1Δ17O(2/1H) in water. Derivatives of the heavy atom shielding constants with respect to extensions in the

APA, Harvard, Vancouver, ISO, and other styles

15

Perrin, Charles L. "Comment on “The role of electrostatic induction in secondary isotope effects on acidity” by E. A. Halevi, New J. Chem., 2014, 38, 3840." New Journal of Chemistry 39, no. 2 (2015): 1517–21. http://dx.doi.org/10.1039/c4nj01887g.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Fang, Yao-ren, Zhu-gen Lai, and Kenneth Charles Westaway. "Isotope effects in nucleophilic substitution reactions X. The effect of changing the nucleophilic atom on ion-pairing in an SN2 reaction." Canadian Journal of Chemistry 76, no. 6 (1998): 758–64. http://dx.doi.org/10.1139/v98-056.

Full text

Abstract:

The effect of ion-pairing in an SN2 reaction is very different when the nucleophilic atom is changed from sulfur to oxygen, i.e., changing the nucleophile from thiophenoxide ion to phenoxide ion. When the nucleophile is sodium thiophenoxide, ion-pairing markedly alters the secondary α -deuterium kinetic isotope effect (transition state structure) and the substituent effect found by changing the para substituent on the nucleophile. When the nucleophile is sodium phenoxide, ion-pairing does not significantly affect the secondary α -deuterium or the chlorine leaving group kinetic isotope effects

APA, Harvard, Vancouver, ISO, and other styles

17

Muchall, Heidi M., and Nick H. Werstiuk. "A computational study on the sources of deuterium secondary kinetic isotope effects in carbocation-forming reactions." Canadian Journal of Chemistry 76, no. 12 (1998): 1926–30. http://dx.doi.org/10.1139/v98-234.

Full text

Abstract:

Calculations at the HF-DFT hybrid Becke3LYP level of theory have been undertaken on protonated 2-exo- and 2-endo-norbornanols as model substrates for 2-exo- and 2-endo-norbornyl brosylates to explore the source of the experimentally determined deuterium secondary kinetic isotope effects (KIEs). Calculations on protonated alcohols as models reproduce the "normal" behaviour of 2-endo substrate 5. The observed endo γ-KIE in the 7-unsubstituted 2-exo system 4 is shown to arise from internal return, while those in the 7-chloro substituted 2-exo substrates 1 and 2 can be explained with competing 1,3

APA, Harvard, Vancouver, ISO, and other styles

18

Baldwin, John E., and Stephanie R. Singer. "Deuterium kinetic isotope effects on the thermal isomerizations of deuteriocyclopropane to deuterium-labeled propenes." Canadian Journal of Chemistry 83, no. 9 (2005): 1510–15. http://dx.doi.org/10.1139/v05-167.

Full text

Abstract:

The gas-phase thermal isomerizations of deuteriocyclopropane to the four possible monodeuterium-labeled propenes have been followed at 435 °C. The observed distribution of products provides estimates of two deuterium kinetic isotope effects, the secondary [Formula: see text] for the carboncarbon bond cleavage leading to trimethylene diradical reactive intermediates and the primary [Formula: see text] ratio for a [1,2] shift of a hydrogen or deuterium leading from the diradical to a labeled propene. The values determined are [Formula: see text] = 1.09 ± 0.03 and [Formula: see text] = 1.55 ± 0.

APA, Harvard, Vancouver, ISO, and other styles

19

Kovach, Ildiko M., Son Do, and Richard L. Schowen. "?-Secondary deuterium isotope effect and solvent isotope effects in catalysis by subtilisin BPN?" Journal of Physical Organic Chemistry 3, no. 4 (1990): 260–65. http://dx.doi.org/10.1002/poc.610030409.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Perrin, Charles L., and Phaneendrasai Karri. "Position-Specific Secondary Deuterium Isotope Effects on Basicity of Pyridine." Journal of the American Chemical Society 132, no. 34 (2010): 12145–49. http://dx.doi.org/10.1021/ja105331g.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Perrin, Charles L., and Yanmei Dong. "Nonadditivity of Secondary Deuterium Isotope Effects on Basicity of Trimethylamine." Journal of the American Chemical Society 130, no. 33 (2008): 11143–48. http://dx.doi.org/10.1021/ja803084w.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Rossi, Maria Helena, Antonia Sonia Stachissini, and Luciano Do Amaral. "Secondary .alpha.-deuterium isotope effects in the formation of imines." Journal of Organic Chemistry 55, no. 4 (1990): 1300–1303. http://dx.doi.org/10.1021/jo00291a038.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Mann, Brian E., Peter W. Cutts, James McKenna, Jean M. McKenna, and Catriona M. Spencer. "Secondary Deuterium Kinetic Isotope Effects in Enantioselective Hydroborations with(+)-Diisopinocampheylborane." Angewandte Chemie International Edition in English 25, no. 6 (1986): 577–78. http://dx.doi.org/10.1002/anie.198605771.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Kim, Sung Chun, Amar N. Singh, and Frank M. Raushel. "Analysis of the galactosyltransferase reaction by positional isotope exchange and secondary deuterium isotope effects." Archives of Biochemistry and Biophysics 267, no. 1 (1988): 54–59. http://dx.doi.org/10.1016/0003-9861(88)90007-0.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Holm, Torkil, Jørgen Øgaard Madsen, Claus Nielsen, et al. "Secondary beta-Deuterium Kinetic Isotope Effects in Reactions of Grignard Reagents." Acta Chemica Scandinavica 46 (1992): 985–88. http://dx.doi.org/10.3891/acta.chem.scand.46-0985.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Young, Paul R., and Patrick E. McMahon. "Iodide reduction of sulfilimines. Secondary deuterium isotope effects on sulfurane formation." Journal of Organic Chemistry 51, no. 21 (1986): 4078–80. http://dx.doi.org/10.1021/jo00371a035.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Westaway, Kenneth Charles, Zbigniew Waszczylo, Peter James Smith, and Kanchugarakoppal S. Rangappa. "Large concentration effects on the magnitude of secondary alpha-deuterium kinetic isotope effects." Tetrahedron Letters 26, no. 1 (1985): 25–28. http://dx.doi.org/10.1016/s0040-4039(00)98456-9.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Guo, X., and M. L. Sinnott. "A kinetic-isotope-effect study of catalysis by Vibrio cholerae neuraminidase." Biochemical Journal 294, no. 3 (1993): 653–56. http://dx.doi.org/10.1042/bj2940653.

Full text

Abstract:

Michaelis-Menten parameters for hydrolysis of seven aryl N-acetyl alpha-D-neuraminides by Vibrio cholerae neuraminidase at pH 5.0 correlate well with the leaving-group pKa (delta pK 3.0; beta 1g (V/K) = -0.73, r = -0.93; beta 1g (V) = -0.25; r = -0.95). The beta-deuterium kinetic-isotope effect, beta D2(V), for the p-nitrophenyl glycoside is the same at the optimum pH of 5.0 (1.059 +/- 0.010) as at pH 8.0 (1.053 +/- 0.010), suggesting that isotope effects are fully expressed with this substrate at the optimum pH. For this substrate at pH 5.0, leaving group 18O effects are 18(V) = 1.040 +/- 0.0

APA, Harvard, Vancouver, ISO, and other styles

29

Leighton, Kevin L., and Roderick E. Wasylishen. "Deuterium isotope effects on the 119Sn shielding constants and spin–spin coupling constants in stannane and the stannonium cation." Canadian Journal of Chemistry 65, no. 7 (1987): 1469–73. http://dx.doi.org/10.1139/v87-250.

Full text

Abstract:

Deuterium induced isotope effects on the 119Sn chemical shielding constants have been measured for stannane and the stannonium cation; they are found to be approximately −0.403 ppm/D and −0.05 ppm/D respectively. The 119Sn shifts in the series SnDnH4−n (n ≤ 4) deviate from additivity as predicted by Jameson and Osten. The primary and secondary isotope effects on Sn–H spin–spin coupling for stannane were obtained and are −2.8 Hz and −1.7 Hz respectively. The primary isotope effect for Sn–H spin–spin coupling for the stannonium cation was found to be −11.6 ± 7 Hz; an accurate value for the secon

APA, Harvard, Vancouver, ISO, and other styles

30

Smith, Peter James, Kanchugarakoppal S. Rangappa та Kenneth Charles Westaway. "Secondary α-deuterium kinetic isotope effects for the E2 reaction of the 2-phenylethyl halides with tert-butoxide ion in tert-butyl alcohol". Canadian Journal of Chemistry 63, № 1 (1985): 100–102. http://dx.doi.org/10.1139/v85-017.

Full text

Abstract:

Secondary α-deuterium kinetic isotope effects have been determined for the elimination reactions of 2-phenylethyl halides with tert-butoxide in tert-butyl alcohol at 40 °C in the presence and absence of the crown ether 18C6. The second-order rate constant k2 and the normal (kH/kD)α effect remained constant when the tert-butoxide concentration was varied for reaction of the iodo and bromo compounds. However, both the magnitude of k2 and the secondary α-deuterium isotope effect were significantly dependent on [t-BuO−] when chlorine and fluorine are the leaving groups. It is noteworthy that (kH/k

APA, Harvard, Vancouver, ISO, and other styles

31

Perrin, Charles L., and Yanmei Dong. "Secondary Deuterium Isotope Effects on the Acidity of Carboxylic Acids and Phenols." Journal of the American Chemical Society 129, no. 14 (2007): 4490–97. http://dx.doi.org/10.1021/ja069103t.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Adediran, S. A., S. A. Deraniyagala, Yang Xu та R. F. Pratt. "β-Secondary and Solvent Deuterium Kinetic Isotope Effects on β-Lactamase Catalysis†". Biochemistry 35, № 11 (1996): 3604–13. http://dx.doi.org/10.1021/bi952107i.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Barnes, John A., та Ian H. Williams. "Theoretical investigation of the origin of secondary α-deuterium kinetic isotope effects". J. Chem. Soc., Chem. Commun., № 16 (1993): 1286–87. http://dx.doi.org/10.1039/c39930001286.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Vujanić, P., E. Gacs-Baitz, Z. Meić, T. Šuste, and V. Smrečki. "Primary and secondary deuterium-induced isotope effects for13C NMR parameters of benzaldehyde." Magnetic Resonance in Chemistry 33, no. 6 (1995): 426–30. http://dx.doi.org/10.1002/mrc.1260330604.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

Dzierzawska, Joanna, Arkadiusz Jarota, Michal Karolak, et al. "Carbon and secondary deuterium kinetic isotope effects on SN2 methyl transfer reactions." Journal of Physical Organic Chemistry 20, no. 12 (2007): 1114–20. http://dx.doi.org/10.1002/poc.1267.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Kluger, Ronald, and Michael Brandl. "Secondary .beta.-deuterium isotope effects in decarboxylation and elimination reactions of .alpha.-lactylthiamin: intrinsic isotope effects of pyruvate decarboxylase." Journal of the American Chemical Society 108, no. 24 (1986): 7828–32. http://dx.doi.org/10.1021/ja00284a056.

Full text

APA, Harvard, Vancouver, ISO, and other styles

37

Chickos, James S. "Secondary deuterium isotope effects in the thermolysis of 2,2-dimethyl-1-vinyl-cyclobutane." Journal of the Chemical Society, Perkin Transactions 2, no. 8 (1987): 1109. http://dx.doi.org/10.1039/p29870001109.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Gajewski, Joseph J., Wojciech Bocian, Nancy L. Brichford, and Johanna L. Henderson. "Secondary Deuterium Kinetic Isotope Effects in Irreversible Additions of Allyl Reagents to Benzaldehyde." Journal of Organic Chemistry 67, no. 12 (2002): 4236–40. http://dx.doi.org/10.1021/jo0164002.

Full text

APA, Harvard, Vancouver, ISO, and other styles

39

Kluger, Ronald, and Michael Brandl. ".beta.-Deuterium secondary isotope effects in heterolytic decarboxylation reactions. Manifestations of negative hyperconjugation." Journal of Organic Chemistry 51, no. 21 (1986): 3964–68. http://dx.doi.org/10.1021/jo00371a010.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Perrin, Charles L., and Agnes Flach. "No Contribution of an Inductive Effect to Secondary Deuterium Isotope Effects on Acidity." Angewandte Chemie International Edition 50, no. 33 (2011): 7674–76. http://dx.doi.org/10.1002/anie.201102125.

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Sergeyeva, N. D., N. M. Sergeyev, and W. T. Raynes. "Deuterium-induced primary and secondary isotope effects on13C,H coupling constants in halomethanes." Magnetic Resonance in Chemistry 36, no. 4 (1998): 255–60. http://dx.doi.org/10.1002/(sici)1097-458x(199804)36:4<255::aid-omr259>3.0.co;2-4.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Perrin, Charles L., and Agnes Flach. "No Contribution of an Inductive Effect to Secondary Deuterium Isotope Effects on Acidity." Angewandte Chemie 123, no. 33 (2011): 7816–18. http://dx.doi.org/10.1002/ange.201102125.

Full text

APA, Harvard, Vancouver, ISO, and other styles

43

Okazaki, Masaharu, Kazumi Toriyama, Keichi Nunome, Hachizo Muto, and Takeshi Shiga. "Two independent isotope effects and their magnetic field dependences in the photoreduction of menadione in deuterium labeled SDS micellar solutions. A spin trapping study." Canadian Journal of Chemistry 66, no. 8 (1988): 1832–35. http://dx.doi.org/10.1139/v88-296.

Full text

Abstract:

Spin adduct yields in the photoreduction of menadione (2-methylnaphthoquinone) in isotope labeled micellar solutions were measured as functions of the external magnetic field. As surfactants, ordinary SDS, perdeuteriated SDS, and a mixture of the two were employed. In a mixed micellar solution, a normal isotope effect on the spin adduct yield was observed. On the other hand, in the pure micellar solutions with each of the former two surfactants, a reversed isotope effect was observed. These two apparent isotope effects depend on the external magnetic field and were separated into two independe

APA, Harvard, Vancouver, ISO, and other styles

44

Tschuikow-Roux, E., Jan Niedzielski, and F. Faraji. "Competitive photochlorination and kinetic isotope effects for hydrogen/deuterium abstraction from the methyl group in C2H6, C2D6, CH3CHCl2, CD3CHCl2, CH3CCl3, and CD3CCl3." Canadian Journal of Chemistry 63, no. 5 (1985): 1093–99. http://dx.doi.org/10.1139/v85-185.

Full text

Abstract:

The abstraction of hydrogen and deuterium from ethane, 1,1-dichloroethane, 1,1,1-trichloroethane, and some of their deuterated analogs by photochemically generated ground state chlorine atoms has been investigated in the temperature range 7–95 °C using methane as competitor. Rate constants and their temperature coefficients are reported for the following reactions:[Formula: see text]An Arrhenius law temperature dependence was observed in all cases. Mixed primary and α-secondary kinetic isotope effects are k1/k2 = 2.79 ± 0.27, k4/k6 = 4.13 ± 0.32, k7/k8 = 1.46 ± 0.12 at 298 K and decrease to k1

APA, Harvard, Vancouver, ISO, and other styles

45

Lai, Zhu-Gen, and Kenneth Charles Westaway. "Isotope effects in nucleophilic substitution reactions. VII. The effect of ion pairing on the substituent effects on SN2 transition state structure." Canadian Journal of Chemistry 67, no. 1 (1989): 21–26. http://dx.doi.org/10.1139/v89-004.

Full text

Abstract:

The secondary α-deuterium kinetic isotope effects and substituent effect found in the SN2 reactions between a series of para-substituted sodium thiophenoxides and benzyldimethylphenylammonium ion are significantly larger when the reacting nucleophile is a free ion than when it is a solvent-separated ion pair complex. Tighter transition states are found when a poorer nucleophile is used in both the free ion and ion pair reactions. Also, the transition states for all but one substituent are tighter for the reactions with the solvent-separated ion pair complex than with the free ion. Hammett ρ va

APA, Harvard, Vancouver, ISO, and other styles

46

Extier, Thomas, Thibaut Caley, and Didier M. Roche. "Modelling water isotopologues (¹H²H¹⁶O, ¹H₂¹⁷O) in the coupled numerical climate model iLOVECLIM (version 1.1.5)." Geoscientific Model Development 17, no. 5 (2024): 2117–39. http://dx.doi.org/10.5194/gmd-17-2117-2024.

Full text

Abstract:

Abstract. Stable water isotopes are used to infer changes in the hydrological cycle for different climate periods and various climatic archives. Following previous developments of δ18O in the coupled climate model of intermediate complexity, iLOVECLIM, we present here the implementation of the 1H2H16O and 1H217O water isotopes in the different components of this model and calculate the associated secondary markers deuterium excess (d-excess) and oxygen-17 excess (17O-excess) in the atmosphere and ocean. So far, the latter has only been modelled by the atmospheric model LMDZ4. Results of a 5000

APA, Harvard, Vancouver, ISO, and other styles

47

Pham, Thuy Van, та Robert A. McClelland. "The nature of the transition state in diarylmethyl cation nucleophile combination reactions as probed by secondary α-deuterium isotope effects". Canadian Journal of Chemistry 79, № 12 (2001): 1887–97. http://dx.doi.org/10.1139/v01-182.

Full text

Abstract:

Transition-state structures for the carbocationnucleophile combination reactions of (4-substituted-4'- methoxydiphenyl)methyl cations with water, chloride, and bromide ions in acetonitrilewater mixtures have been investigated by measuring the secondary α-deuterium kinetic and equilibrium isotope effects. Rate constants in the combination direction were measured with laser flash photolysis. Equilibrium constants were measured for the water reaction by a comparison method in moderately concentrated sulfuric acid solutions, for the bromide reaction via the observation of reversible combination,

APA, Harvard, Vancouver, ISO, and other styles

48

Suarez, Javier, and Vern L. Schramm. "Isotope-specific and amino acid-specific heavy atom substitutions alter barrier crossing in human purine nucleoside phosphorylase." Proceedings of the National Academy of Sciences 112, no. 36 (2015): 11247–51. http://dx.doi.org/10.1073/pnas.1513956112.

Full text

Abstract:

Computational chemistry predicts that atomic motions on the femtosecond timescale are coupled to transition-state formation (barrier-crossing) in human purine nucleoside phosphorylase (PNP). The prediction is experimentally supported by slowed catalytic site chemistry in isotopically labeled PNP (13C, 15N, and 2H). However, other explanations are possible, including altered volume or bond polarization from carbon-deuterium bonds or propagation of the femtosecond bond motions into slower (nanoseconds to milliseconds) motions of the larger protein architecture to alter catalytic site chemistry.

APA, Harvard, Vancouver, ISO, and other styles

49

Bentley, T. William. "Secondary α-Deuterium Kinetic Isotope Effects: Assumptions Simplifying Interpretations of Mechanisms of Solvolyses of Secondary Alkyl Sulfonates". Journal of Organic Chemistry 69, № 5 (2004): 1756–59. http://dx.doi.org/10.1021/jo035793x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Gajewski, Joseph J., and Kyle R. Gee. "Solvent, counterion, and secondary deuterium kinetic isotope effects in the anionic oxy Cope rearrangement." Journal of the American Chemical Society 113, no. 3 (1991): 967–71. http://dx.doi.org/10.1021/ja00003a033.

Full text

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!