Unusual Reaction of 1,2-Dihydro- 5,6-tetramethylenespiro{cyclohexane-2-thieno- 2,3-dpyrimidine-4(3H)-thione} with 2-Bromo-4'-methylacetophenone

摘要

1,2-Dihydro-5,6-tetramethylenespiro {cyclohexane-2-thieno2,3-dpyrimidme-4(3H)-thione} I was alkylated with ethyl iodide 1 and α-chloroaceta-nilide 2 in DMF solution in the presence of KOH involving the sulfur atom of thioxo-group to give the corresponding thioethers. The use of 2-bromo- 4'-methylacetophenone II in this reaction as the alkylating agent led unexpectedly to the cross-recyclization of the pyrimidine fragment of the heterocyclic system I and to the formation of 2-(2-hydroxy-4,5,6,7-tetrahydrobenzobthiophen-3-yl)-4-(4-methylphenyl)thiazole III.