Efficient one-pot synthesis of cyclopenta[b]thiophen-1-ones and 1,3-di(2-thiophenyl)propan-1-ones from thiophenes

Article abstract of DOI:10.1055/s-1997-1207

The reaction of N,N-dimethylacrylamide/triflic anhydride complex with substituted thiophenes led to the corresponding cyclopenta[b]thiophen-1-ones and 1,3-di(2-thiophenyl)propan-1-ones. The application of 2-bromo-N,N-dimethylacrylamide in this reaction allows 2-bromo-substituted five- or seven-membered thiophene-fused cyclic ketones to be obtained.