Benzopyrans. Part 42. Reactions of 4-Oxo-4<i>H</i>-1-benzopyran-3-carbaldehyde with some active methylene compounds in the presence of ammonia
作者:Chandra Kanta Ghosh、Anirban Ray、Amarendra Patra
DOI:10.1002/jhet.5570380632
日期:2001.11
The title aldehyde 1 in the presence of ammonia gives the pyridine derivatives 9-11 respectively with acetylacetone, diethyl malonate and ethyl cyanoacetate, and ethyl (or methyl)-l-benzopyrano[4,3-b]pyri-dine-3-carboxylate 22 (or 23) with ethyl (or methyl) acetoacetate. Acetylacetone pretreated with ammonia condenses with 1 giving the fused pyridine 24. Ammonia converts the ester 6 to the pyridine