Bis(aldehydes): Versatile precursors for novel bis(14H‐dibenzo[a,j]xanthenes), bis(pyrano[3,2‐c:5,6‐c']dichromenedione), and bis(dihydrobenzo[a]xanthenones) via multicomponent reactions

Abstract

AbstractA synthesis of novel bis(4‐(14H‐dibenzo[a,j]xanthenes) and bis(dihydro‐8H‐benzo[a]xanthenones) was performed in good yields via pseudo‐multicomponent, or multicomponent reactions, of bis‐aldehydes with four equivalents of β‐naphthol or with a mixture of two equivalents of each β‐naphthol and dimedone in the presence of a catalytic amount of p‐toluenesulfonic acid. Bis(pyrano[3,2‐c:5,6‐c′]dichromenediones) or tetrakis(4‐hydroxy‐2H‐chromen‐2‐ones) could also be obtained in good yields through pseudo‐multicomponent reactions of bis(aldehydes) with four molar ratio of 4‐hydroxycoumarin.