作者:D. Greif、M. Pulst、M. Weißenfels
DOI:10.1055/s-1987-33432
日期:——
The Synthesis of 2H-Thiopyranes from ß-Thioxoaldehydes [4+2]-Cycloaddition reactions between enaminothioketones and activated alkenes, which are described by Quiniou et al.,1-4 usually require relatively harsh reaction conditions, and produce the title compounds only in moderate yields. Much better results can be achieved by a new synthesis of 3-acyl-2H-thiopyranes starting with dicyclohexylammonium salts of monothio-ß-dicarbonyl compounds and unsaturated aldehydes or ketones. The mechanism of this new reaction is characterized by Michael addition followed by an aldol reaction.
从 ß-Thioxoaldehydes 合成 2H-Thiopyranes [4+2]-Cycloaddition reactions between enaminothioketones and activated alkenes,which are described by Quiniou et al.以单硫代-ß-二羰基化合物的二环己基铵盐和不饱和醛或酮为起点,合成 3-acyl-2H-thiopyranes 的新方法可以获得更好的结果。这种新反应的机理是先发生迈克尔加成反应,然后发生醛醇反应。