Abstract A kinetic study is reported for aminolysis of S-4-nitrophenyl X-substituted thiobenzoates 3a-g in 80 mol%/20 mol% DMSO at. Thiol esters 3a-g are 7.8-47.6 fold more reactive than the corresponding oxygen esters (ie, 4-nitrophenyl X-substituted benzoates 1a- g). Such reactivity order appears to be in accordance with the expectation that 4- nitrothiophenoxide in 3a-g is a better nucleofuge than 4-nitrophenoxide in 1a-g since the ...
