P(RNCH2CH2)3N: AN EFFICIENT PROMOTER FOR THE SYNTHESIS OF 3-SUBSTITUTED COUMARINS

ABSTRACT

The title compounds wherein R = Me or i-Pr function as efficient promoters for the formation of coumarins in good to excellent yields (80–95%) from salicylaldehydes and di-activated methylene compounds of the type R′CH₂CO₂Et (R′ = CO₂Et, COMe, CN). Although the yields are not generally superior to those reported in the literature, our methodology is more convenient in that milder conditions and shorter reaction times are facilitated by the use of the aforementioned commercially available catalysts.