33712-36-6Relevant academic research and scientific papers
Chemical pressure effect by selective deuteration in the molecular-based conductor, 2,5-dimethyl-N,N'-dicyano-p-benzoquinone immine-copper salt, (DMe-DCNQI)2Cu
Aonuma, Shuji,Sawa, Hiroshi,Kato, Reizo
, p. 1541 - 1550 (2007/10/02)
The mixed-valence copper salt of DMe-DCNQI91, where DMe-DCNQI=2,5-dimethyl-N,N'-dicyano-p-benzoquinone diimine) is a molecular conductor whose electrical and magnetic properties are quite sensitive to pressure.We have performed selective deuteriation of the molecule 1.By control of the position and number of deuterium atoms, the low-pressure region (ca. 500 bar) in the pressure-temperature phase diagram of (1)2Cu was reproduced at ambient pressure.The equivalency of the deuteriation and pressure effects is explained from steric origins; 'contraction' aroused by the slightly shorter C-D bond (steric isotope effect) and 'constriction' by pressure.
Side Chain Hydroxylation of Aromatic Compounds by Fungi. Part 4. Influence of the para Substituent on Kinetic Isotope Effects During Benzylic Hydroxylation by Mortierella isabellina
Holland, Herbert L.,Brown, Frances M.,Conn, Morgan
, p. 1651 - 1655 (2007/10/02)
The benzylic hydroxylation of a series of para-substituted toluenes by the fungus Mortierella isabellina has been studied by using CD3, CHD2, and CH2D methyl labelled substrates.Inter- and intramolecular primary and secondary deuterium kinetic isotope effect ratios have been determined: the intermolecular primary effects are maximal with strongly electron-withdrawing para substituents (R = CN and CF3), while the intramolecular primary effects are minimal for R = H but increase in instances where R is electron donating or withdrawing.These results are interpreted in terms of a dependence of the hydroxylation mechanism on the nature of the para substituent.
Isotope effects in nucleophilic substitution reactions. IV. The effect of changing a substituent at the α carbon on the structure os SN2 transition states
Westaway, Kenneth Charles,Waszczylo, Zbigniew
, p. 2500 - 2520 (2007/10/02)
Kinetic studies, secondary α-deuterium kinetic isotope effects, primary chlorine kinetic isotope effects (1), Hammett ρ values determined by changing the substituent in the nucleophile, and activation parameters have been used to determine the detailed (relative) structures of the transition states for the S2 reactions between para-substituted benzyl chlorides and thiophenoxide ion.A rationale for the U-shaped Hammett ρ plots observed when para-substituted benzyl compounds react with negatively charged nucleophiles is also presented.
