N. Takeda, N. Tokitoh, R. Okazaki
1997
Citations
0
Influential Citations
20
Citations
Journal
Chemistry: A European Journal
Abstract
The first rotational isomers of thiobenzaldehydes, TbtCHS (2a and 2b; Tbt = 2,4,6-tris[bis(trimethylsilyl)methyl]phenyl), were synthesized and isolated as stable crystalline compounds by the desulfurization of the corresponding overcrowded cyclic polysulfides TbtCHSn (n = 5 or 8) with phosphine reagents. The molecular structures of 2a and 2b in the solid state, determined by X-ray crystallographic analysis, differed in their conformations, which were essentially identical with those in solution as revealed by 1H{1H} nuclear Overhauser effect (NOE) experiments. The isomeric thiobenzaldehydes 2a and 2b were found to undergo thermal interconversion. A kinetic study of this process gave reasonable kinetic and thermodynamic parameters for conformational isomerizations of this type. Interesting differences in reactivity among the two isomers 2a,b and 2,4,6-tri-tert-butylthiobenzaldehyde (1) were shown in the reactions with hydrazine and m-chloroperoxybenzoic acid.