Facile Synthesis of (2-Amino-3-(benzothiazol-2-yl)-4H-chromen- 4-yl)phosphonate Derivatives under Mild Conditions

Abstract

A series of (2-amino-3-(benzothiazol-2-yl)-4H-chromen-4-yl)phosphonate derivatives were synthesized in good to excellent yields by Michael addition/cyclization of diphenyl phosphite to diverse substituted (E)-2-(benzothiazol-2-yl)-3-(2-hydroxyphenyl)acrylonitriles under catalyst-free condition in water. Meanwhile, one-pot three component reaction of salicylaldehyde, 2-(benzothiazol-2-yl)acetonitrile and diphenyl phosphate was also tested using Et 3 N as catalyst to synthesize these phosphonate derivatives