Elimination–addition mechanisms of acyl group transfer: evidence for rate-limiting breakdown of a sulphene-2,4-dinitrophenoxide ion encounter complex in the base-catalysed hydrolysis of 2,4-dinitrophenyl arylmethanesulphonate esters

Abstract

The base-catalysed hydrolysis of 2,4-dinitrophenyl arylmethanesulphonate esters via an E1cB_i mechanism undergoes a change in rate limiting step in pyridine buffers of high concentration from proton transfer to breakdown of a sulphene-2,4-dinitrophenoxide ion encounter complex.