Kinetic Evidence for the Formation of a Tetrahedral Intermediate in the Aqueous Solvolysis of Ethyl Trifluorothiolacetate

Photolysis of phenylacetic acid and methyl phenylacetate in methanol

“…The increased yields of carbon dioxide at higher temperatures may be evidence for a secondary reaction, e.g., from carboxyl radical. But the major role of carboxyl in our scheme (1) is that it provides a plausible alternate to the formation of hydrogen atoms and eventually of molecular hydrogen. Moreover, the carboxyl radical is a primary product of the thermolysis of 1; such studies have, in fact, led to an assignment of the dissociation energy of the benzyl to carboxyl bond, Z>(C6H6CH2-COOH) = 55 kcal/mol.23 Dissociation of the carboxyl radical to carbon dioxide and a hydrogen atom is endothermic by ca.…”

“…In the absence of interferences, the amount of bibenzyl (BB) or toluene in a cyclohexane extract could be determined by comparing the uv absorption spectra with standard solutions. In the concentration range of interest, e.g., [1][2][3][4][5] 6 Columns: Pac Q or Porapac Q polymer beads, 120-150 mesh, in 0.25 in. X 5 ft aluminum; OV-17 or 5% OV-17 on Anachrom ABS, 70-80 mesh, in 0.25 in.…”

“…An internal standard of 70 µ of methyl undecanoate (>95%) was added to each solution, prior to its injection onto an OV-17 column. The concentrations of 1 in the original samples were determined by comparison of the ratios of the peak heights and peak areas with standard solutions; both peak height and peak area ratios were linear functions of [1] or [2],…”

“…and Joschek have surveyed a large number of aromatic molecules for the formation of the solvated electron by flash photolysis.2 Subsequently, detailed mechanisms and product patterns were developed for the photochemical behavior of phenols and related derivatives.3 Here, we are concerned with the several routes by which irradiated phenylacetic acid (1) and methyl phenylacetate (2) go to their products.4 Although 1 might be regarded as the parent of some acids and a model for others, it turns out that this view could be misleading with respect to the photobehavior of carboxylic acid derivatives in general.5 (1) Taken from the Ph.D. Thesis of T. O. M., Illinois Institute of Technology, 1970. Financial support from the Federal Water Pollution Control Administration in the form of a fellowship for T. O. M. and from Public Health Service Grant GM 7021 is gratefully acknowledged.…”

“…The nmr spectrum of the polymer indicates a high degree of reduction even though some benzyl groups are still evident. 1 The equivalent weight of ca. 180 as compared to 136 for 1 also indicates that some nonacid groups, e.g., benzyl, hydroxymethyl, have been incorporated.…”