Reactions With Cyanothioacetamide Derivative: Synthesis and Reactions of Some Thieno[2,2-B]pyridine, Pyridothienopyridazine, Pyrazolo[3,4=b]pyridine and Pyridopyrazolo-1,2,4-Triazine Derivatives

Thiocarboxamidocinnaonihile derivatives 3a,b reacted with ethyl-benzoylacetate (4) to give pyridinethione derivatives 5a,b which were used as starting materials for synthesis of several hetero-cyclic compounds. Reactions with phenacyl bromides 6a,b, chloroacetone (8), α-chloraacetylacetone and methyl iodide gave thieno[2,3-b]pyridines 7a-d. 2-S-methylacetylpyridine derivatives 9a,b 2-S-methyldiacetyl pyridine derivatives 114b and 2-S-methyl pyridine derivatives 14a,b respectively. Several cyclization reactions were performed with 10% KOH, nitrous acid and hydrazine hydrate to give an additional ring on 9a,b, 10a,b, 11a,b and 14a,b.