Phosphorodithioates containing carboxylic acid ester and amide groups

9 Phosphorodithioates containing carboxylic acid ester and amide groups 

Cassaday c/ al. (1948) prepared several S-carbamoylmethyl phosphorodithioates by the reaction of the salts of 0,0-dialkyl phosphorodithioic acids with various N-substituted chloroacetamides, and investigated their biological properties. Of these, practical importance has been attained by O.O-dimethyl-S-(N-methylcarbamoyl)-methyl phosphorodithioate, known by the name dimethoate (85). 

Due to its great practical importance, several other methods have been developed for the preparation of dimethoate. According to the process of Kochmann et al. 

The process of Young and Berkelhammer (1959) is also based on the formation of the amide group as the last step. According to this process, 0,0-dimethyl- 

S-carboxymethyl phosphorodithicfete (86) is reacted with dimethyl phosphoro-chloridate, and the mixed anhydride formed is treated with methylamine  

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