A new reaction of acid chlorides. Intramolecular ortho-chlorination
作者:Maureen Byers、Alexander R. Forrester、I. Lennox John、Ronald H. Thomson
DOI:10.1039/p19810001092
日期:——
2-(2-Arylazophenoxy)-2-methylpropanoic acids (1) react with thionyl chloride to form 4-(2-chloroanilino)-benzoxazinones (3) in high yield. The reaction proceeds through the acidchloride which undergoes cyclisation with intramolecular electrophilic transfer of the chlorine to ring B. This selective ortho-chlorination is general for azo-acids (1) in which ring B contains a free ortho-position and –M