Reactions of 4-substituted tetrafluoropyridine derivatives with sulfur nucleophiles: SNAr and annelation processes

Reactions of model sulfur centred nucleophiles with 4-nitro-, 4-phenylsulfonyl- and 4-cyano-tetrafluoropyridine gave products arising from substitution of the nitro- and sulfonyl substituent or ring fluorine respectively. Ring fused products are formed upon reaction of 4-cyano-tetrafluoropyridine with mercapto-acetic acid ethyl ester.