Self-Alkylation of some Dialkyl Phosphate Esters

Abstract

THE alkylation of tertiary amines by neutral phosphate esters has been reported¹, and in one instance self-methylation has been observed². Thus, Andrews et al. found that (m-dimethyl phosphato)-N-dimethylaniline forms the quaternary zwitterion slowly at room temperature and rapidly on heating. Hobbiger³ found that the anticholinesterase activity of the dimethyl, diethyl and di-isopropyl ternary compounds increased in water, which suggests that (dialkyl phosphato)-N-dimethylalkylanilinium compounds are formed by the bimolecular reaction: The dialkyl quaternary compounds are powerful inhibitors of cholinesterase⁴, whereas it is unlikely that the zwitterion is.