Synthesis of all of the monomethyl isomers of naphtho[2,1‐b]thiophene

All isomers of the monomethylnaphtho[2,1‐b]thiophenes were synthesized by photocyclization of 2‐styryl‐thiophenes which were either prepared by the Wadsworth‐Emmons reaction or by the condensation of 2‐lithiothiophene with the corresponding carbonyl compounds.