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
在氨存在下的标题醛1分别与乙酰丙酮,丙二酸二乙酯和氰基乙酸乙酯,以及(或甲基)-1-苯并吡喃并[4,3 - b ]吡啶-丁-3-羧酸酯分别给出吡啶衍生物9-11 22(或23)用乙酰乙酸乙酯(或甲基)。用氨预处理的乙酰丙酮与1缩合,得到稠合的吡啶24。氨将酯6转化为吡啶13或14。22和23的铬酸氧化分别提供香豆素吡啶25和26。