

MICROWAVE-ASSISTED SEQUENTIAL THREE-COMPONENT SYNTHESIS OF PYRROLYL-SUBSTITUTED CHROMENO[2,3-c]ISOQUINOLIN-5-AMINES

Abstract
Sequential one-pot domino reaction of homophthalonitrile, salicylaldehydes, and pyrroles in basic media under MW irradiation results in the formation of novel chromeno[2,3-c]isoquinolin-5-amines. The transformation represents a domino sequence that starts with Knoevenagel condensation, followed by two nucleophilic cyclizations, consecutively forming 2-iminochromene and 5-iminoisoquinoline cycles. Michael addition of the pyrrole unit to the chromene cycle finishes the transformation. The reaction tolerates various salicylaldehydes and pyrroles, producing target molecules with good 45–67% yields.
Keywords
2-aminochromene; isoquinolin-5-amines; salicylaldehyde; domino reaction; multicomponent reaction.
Latvian Institute of Organic Synthesis - Aizkraukles iela, 21, Riga, LV-1006, Latvia - hgs@osi.lv