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The syntheses of the previously unreported k,6-dihydrothieno13 j^-bj thiophene, cyclopentajb]thiophene and cyclopentajjojthiophene are reported. The nuclear magnetic resonance and ultraviolet spectra of these compounds are discussed with respect to possible ring strain in the thiophene nucleus. Several new 2,3“disubstituted thiophene derivatives are also reported. Ethyl 2-amino-4H-indeno [l,2-bJthiophene-3-carboxylate and ethyl 2-amino-8H-indeno£2,l-bJthiophene-3“carbo:xylate were prepared. Attempts to remove the amino and ester functions of the latter oompaund were unsuccessful. 8H-Indeno[2,1-bjthiophene was prepared in good yield in a four step synthesis. Several new derivatives of the 8H-indenoJj2,1-bjthiophene system were prepared. Metalation of 8H-indenojj2, l-b J thiophene occurred in the methylene position while metalation of 2-benzylthiophene occurred in the thiophene ring. Interpretations of the results are discussed. A convenient route to 5}7~dihydrbbisindeno [2,l-b; l',2'-d]thiophene was discovered. Earlier literature reports on the preparation of this compound were found to be incorrect. Molecular orbital calculations were made on the thiophene analogs of fluorene and indene with respect to predicting the acidity of these compounds.