Tandem Wolff rearrangement-“α-cyclization of tertiary amines” sequence: Synthesis of some 1H-2-benzopyran derivatives
作者:Françoise Léost、Bernard Chantegrel、Christian Deshayes
DOI:10.1016/s0040-4020(98)00275-0
日期:1998.6
The thermolyses of dimethyl 1-diazo-2-oxo(2-(N,N-disubstituted aminomethyl)phenyl)-ethylphosphonates6a-e or the related ester 6f afford 1-disubstituted amino-1H-2-benzopyran derivatives 9a-f through a 3-step sequence involving Wolff rearrangement, [1,5] hydride shift and subsequent ring closure. Compounds 9 can be easily transformed into 1-hydroxy-, 1-methoxy- or 1-thiophenoxy-1H-2-benzopyran or isoquinoline
对1-重氮-2-氧代二甲基(2-(N,N-二取代氨基甲基)苯基)-乙基膦酸酯6a-e或相关酯6f进行热解得到1-二取代氨基-1 H -2-苯并吡喃衍生物9a-f通过涉及Wolff重排,[1,5]氢化物转移和随后的闭环的3步序列。通过各种亲核试剂的作用,化合物9可以容易地转化为1-羟基-,1-甲氧基-或1-噻吩氧基-1 H -2-苯并吡喃或异喹啉衍生物。还描述了将该反应扩展至一些类似于6的杂环重氮膦酸酯。