Regioselectivity in the Schmidt Reaction: First Synthesis of Pyrano[3,2-b]azepines
作者:Marijan Kočevar、Franc Pozgan、Slovenko Polanc
DOI:10.3987/com-01-s(k)53
日期:——
The Schmidt reaction of 5,6,7,8-tetrahydro-2H-1-benzopyran-2-ones (1) has been investigated. Derivatives of pyrano[3,2-c]azepines (2) and isomeric pyrano[3,2-b]azepines (3) were isolated by the application of trimethylsilyl azide or sodium azide in a methylene chloride or a chloroform solution in the presence of sulfuric acid At low temperature products (2) were almost sole products, while at higher