DIETHYL N,N-DIMETHYLAMINOMETHYLENEMALONATE IN THE SYNTHESIS OF FUSED HETEROCYCLIC-SYSTEMS

The reactions of diethyl N,N-dimethylaminomethylenemalonate (3) with N - and C- nucleophiles were studied. In the reaction of 3 with heterocy clic amines 4, with the amino group attached at alpha-position in resp ect to the ring nitrogen atom, substitution of the dimethylamino group in 3 with the heterocyclic amino took place to give diethyl heteroary laminomethylenemalonates 5, which can cyclize into fused azino- 6 or a zolopyrimidinones 7. In the reaction of 3 with the compound with an ac tive methylene group attached at alpha-position in regard to the ring nitrogen atom, such as pyridinylacetonitrile (8), ethyl pyridinyl- (9) , and quinolinylacetate (10), fused quinolizines 11 and 12, and benzo[ c]quinolizine 13 were formed, respectively. Heterocyclic systems with an active or potentially active methylene group incorporated in the ri ng system, such as pyrazole 14, pyrimidine 15, and pyridine derivative 18, gave with 3 fused pyranones 16, 17, and 19, and dihydroxynaphthal enes 22 and 23 naphtho[2,1-b]pyranones 24 and 25.