Synthesis of sulfur-containing heterocyclic compounds by cyclocondensationof acetylenic derivatives of anthraquinone with sodium sulfide

Abstract

Reaction of vic- alkynylchloro- and vic- chloro-(1-oxoalk-2-ynyl)- anthraquinones with Na2S in ethanol, with short heating, has been shown to afford anthrathiophenediones and anthrathiopyrantriones, respectively, generally in good yields. Under the same conditions, 1-alkynylanthraquinones also undergo cyclocondensation to give anthra[2,1-b]thiophene-6,11-diones.