Thioamides, from Grignard reagents

Dithioacids have been generated from carbon disulfide with Grignard reagents or alkyl lithium at 0 °C. Subsequent treatment with sulfonamide in situ gives the corresponding both aliphatic as well as aromatic thioamides in 70-90% yields (Scheme 10).31... 

Thioacylation of amines have been developed as a synthetic method for thioamides. Various thioacylating agents can be used. The dithioic acid salts 41, which are generated in situ from organolithium or Grignard reagents with CS2,... 

Thioamides can be obtained in 40—60% yield by the reaction of Grignard reagents with triphenylphosphine thiocyanate. In a continuation of earlier work, Yoshida s group has found that a large range of enolates (e.g. those from ketones, esters, amides, acetoacetates) add in a conjugative manner to a,jS-unsaturated thioamides the derivatives thus obtained can easily be converted into esters and amides (cf. 3, 253). 

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