Pentatomic heteroaromatic cations. Part VI. New syntheses of aldehydes and ketones by reaction of 1,3-benzodithiolylium salts with Grignard reagents

Abstract

2-Substituted and 2,2-disubstituted 1,3-benzodithioles are formed when 1,3-benzodithiolylium and 2-phenyl-1,3-benzodithiolylium perchlorates, respectively, react with Grignard reagents. The products can be hydrolysed to aldehydes and ketones by treatment with chloramine τ followed by mercury(II) chloride. This procedure offers a sound alternative method for the synthesis of aldehydes by formylation of Grignard reagents, and it suggests a new route for the total synthesis of symmetric and asymmetric ketones from alkyl and aryl halides via such reagents.