Arylidene Derivatives as Synthons in Heterocyclic Synthesis

Abstract

This review describes the synthetic procedures for the preparation of arylideneacetophenones, arylidenecycloalkanones, 2-arylidene-1-indanones, 2-arylidene-1-tetralones, 2-arylidene-1-benzosuberones, aurones, 1-thioaurones, 3-arylidene-4-chromanones, 3-arylidene-1-thio-4-chromanones, 3-arylideneflavanones, 3-arylidene-1-thioflavanones, arylideneanilines, arylidenemalononitriles, diethyl arylidenemalonates, ethyl arylidenecyanoacetates, arylidenecyanoacetamides, 5-arylidene derivatives of barbituric and thiobarbituric acids, arylidene derivatives of Meldrum’s acid and arylidene derivatives of dimedone. Also, it demonstrates the reactivity of these arylidene derivatives in heterocyclic synthesis with emphasis on the most recent findings. Some of these are the α,β-enones, víz. aurones and 3-arylidene-4-chromanones belong to the natural products. The others are synthetic substances which are convenient and important intermediates for the synthesis of a variety of useful and novel heterocyclic systems.