84017-05-0Relevant articles and documents
Methylation of a Benzene Ring as a Chemical Signal. Marked Changes in the Pattern of Temperature Dependence of the Selectivity in Oxidation of a Pair of Associating Thiols
Endo, Tadashi,Okubo, Akihiro,Kaneko, Yuji,Uehara, Masatoshi,Tasai, Hidetoshi,et al.
, p. 2224 - 2232 (1982)
Temperature dependence of the selectivity has been studied in oxidation of a pair of assotiating thiols, each with the recognition site 1>, with O2 in 80percent (v/v) acetonitrile-20percent water in the range of -10 to 70 deg C.The selectivity for R1=C6H4CH3 shows a minimum at 35 deg C, whereas for R1=C6H5 the selectivity exhibits a maximum at 35 deg C; for R1=C6H4C2H5 plots of the selectivity against temperature shows a sigmoid-like curve.The selectivity in oxidation of a pair of non-associating thiols, 2-(dimethylamino)ethanethiol and a para-substituted benzenethiol, remains practically unaltered with temperature in the same solvent.Though thiol-disulfide exchange reaction proceeds slowly below 35 deg C, the selectivity in the exchange differs entirely from that in the oxidation.It has been found that changes in hydrophobocity with R1 and temperature cannot explain dramatic alterations in the selectivity with R1 and temperature.