The reductive fission of methyl sulphides, 1,3-dithiolans, and a 1,3-oxathiolan by sodium in liquid ammonia

Abstract

The fact that 2,3-dimercaptopropanol can be regenerated from its SS-methylene derivative, but not from its SS-isopropylidene derivative, by sodium in liquid ammonia, is explained by the difference in stability of the respective intermediate alkylthio-derivatives. In a series of 2-(alkylthio)ethanols, only the methylthio-compound is cleaved. The isopropylidene derivatives of cyclohexane-trans-1,2-dithiol, 2-mercaptocyclohexanol, and propane-1,2-dithiol give, respectively, trans-2-(isopropylthio)cyclohexanethiol, trans-2-isopropoxycyclohexanethiol, and a mixture of 2-(isopropylthio)propane-1-thiol and 1-(isopropylthio)propane-2-thiol. In contrast to the last example, the partial cleavage of the isopropylidene derivative of 2,3-dimercaptopropanol occurs only in one direction, to give 2-isopropylthio-3-mercaptopropanol.

The rates of alkaline hydrolysis have been measured for some acetates containing alkylthio- or methoxy-groups. 2-(Alkylthio)ethanols are slowly converted into 1,2-bisalkylthioethanes when boiled with dilute hydrochloric acid.