Reactions of aryl dimethylphosphinothioate esters with anionic oxygen nucleophiles: transition state structure in 70% water-30% ethanol.

ABSTRACT: Aryl dimethylphosphinates, 2, react with anionic oxygen nucleophiles in water via a concerted (A_ND_N) mechanism. With EtO^- in anhydrous ethanol, the mechanism is associative (A_N + D_N), with rate-limiting pentacoordinate intermediate formation. This change in mechanism with solvent change has been ascribed to changes in the nucleophile and leaving group basicities accompanying solvent change. This paper reports on a kinetic analysis of the reactions of the aryl dimethylphosphinothioates, 3a-g, with oxygen nucleophiles in 70% water-30% ethanol (v/v) solvent at 25 °C, reactions known to proceed by a concerted mechanism in water, to test the rationalization stated above, since the nucleophiles and LGs of interest are more basic in aq

SUBMITTER: Kalu GI 

PROVIDER: S-EPMC8695247 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature