Serendipitous synthesis of 4-thioxochromen-2-one derivatives through the one-pot three-component reaction of primary amines, carbon disulfide, and 4-chlorocoumarin-3-carbaldehyde

Coumarins are an important class of natural and synthetic compounds that show various biological activities [1], which often depending on the substituent on the benzopyran moiety. For example, some coumarine derivatives having pyridine substituted at 3- or 4-position of the coumarine ring possess CNS depressant activity [2]. Also a number of coumarin derivatives used as an intermediate to produce various biologically active compounds [3]. In addition, these compounds are useful as organic electroluminescent materials [4]. In this paper we wish to report One-Pot three component reaction between 4-chlorocoumarin-3-carbaldehyde andprimary amines in the presence of carbon disulfide and thriethylamine leads to 4-thioxochromen-2-one derivativesin good to excellent yields.