Jul-Aug 1982 Monomethyl Isomers of Benzo[ò]naphtho[2,l-£Í]thiophene 861 EXPERIMENTAL Melting points were determined on a Thomas Hoover melting point apparatus and are uncorrected. The ir spectra were obtained on a Beckman Acculab 2 spectrometer. 'H-nmr spectra were obtained on a Varian EM 360A spectrometer in the solvents indicated. Chemical shifts are reported in Ô units. Mass spectra were obtained on a Hewlett-Packard model 5980A ...