Chemistry of thienopyridines. XXIX. The reissert‐henze reaction as a route to simple c‐substituents alpha to the heteronitrogen atom

Treatment of a thienopyridine N‐oxide with benzoyl chloride and cyanide ion (Reissert‐Henze reaction) was shown to produce the corresponding cyanothienopyridine (43‐84% yield in three parent systems), wherein the cyano substituent occurs alpha to the heteronitrogen atom. In further transformations (in two systems) the cyano group was converted successively to carbamoyl (66‐89%),and thiocarbamoyl (3543%) functions. For 4‐substituted thieno[2,3‐6]pyridine 7‐oxides, methyl and chloro substituents were retained on Reissert‐Henze reaction, but the nitro group was replaced by CI or H. Some new TV‐oxides and TV‐oxide complexes are reported.