Benzomorphan related compounds. V. Synthesis of thienomorphans

Abstract

A series of thieno [2,3‐ƒ]‐, [3,2‐ƒ]‐ and [3,4‐ƒ]morphans prepared both by the Grewe synthesis and by the reaction of 2‐cyanopyridines with 3‐thienyllithium is described. Furthermore, a new synthetic route to thieno [2,3‐ƒ] morphans from 3‐ketotetrahydrolhiophene is reported. Separation and assignment of the α‐ and β‐diastereomerie structures by means of nmr data is reported. Some side products were isolated and their structures were confirmed on the basis of their spectral data. Mechanisms for their formation are proposed.