SYNTHESIS OF SOME NEW SPIROHETEROCYCLES RELATED TO SPIRO[INDOLINE-3,2'-[1,3]OXATHIALANE]-2,5'-DIONE

The reaction of indole-2,3-dione (1a) and/or 1-methylindole-2,3-dione (1b) with mercaptoacetic acid in the presence of 4-toluenesulfonic aci d as a catalyst afforded spiro[indoline-3,2'-[1,3]oxathialane]-2,5'-di ones (2a, b). Compounds 2a and/or 2b were reacted with the appropriate aliphatic and/or aromatic primary amines to give compounds 3a-j. The reaction of 2a, b with hydrazine hydrate, phenylhydrazine and p-nitrop henylhydrazine yielded spiroderivatives 4a-c. Friedel-Crafts reactions of 2a and 2b with arenes in the presence of aluminium chloride cataly st afforded spiroindoline isothiochroman derivatives 5a-h.