abstract |
Mixtures of (1) a quaternary ammonium salt(s) and (2) 1,4-diazabicyclo[2.2.2]octane are novel catalysts in the process of reacting an alkali metal phenate, pyridinate or pyrimidiate with an O,O-dialkyl phosphorochloridothioate or O-alkyl phenylphosphonochloridothioate to produce the corresponding phosphorothioates and phenylphosphonothioates. The process is conducted under alkaline conditions in a liquid reaction medium. As an example, O,O-diethyl 0-(3,5,6-trichloro-2-pyridyl)phosphorothioate is prepared in excellent yields and purity by reacting sodium 3,5,6-trichloropyridinate with O,O-diethyl phosphorochloridothioate in a stirred methylene chloride-water reaction medium in the presence of a catalytic amount of benzyltriethylammonium chloride and 1,4-diazabicyclo[2.2.2]octane. |