A simple and efficient method has been developed for the rapid synthesis of substituted 4H-1, 4-benzothiazines (3) from 2-aminobenzenethiols (1) and β-ketoester/β-diketones (2) in dry media undermicrowaveirradiation using basic alumina as solidsupport.
Synthesis of Disubstituted 6-Chloro-5-methyl-4H-1,4-benzothiazines: Novel Heterocycles
作者:Ram K. Rathore、Radha R. Gupta
DOI:10.1135/cccc19952209
日期:——
2-Amino-4-chloro-3-methylbenzenethiol in the form of dimer condensed with 8 β-diketones or β-ketoesters to form an enaminoketone or ester intermediate which underwent spontaneous oxidative cyclization to form 6-chloro-5-methyl-2,3-disubstituted 4H-1,4-benzothiazines.