Synthesis of the sulphur analogue of psilocin and some related compounds
Possible routes to NN-dimethyl-2-(4-hydroxy-3-benzo[b]thienyl)ethylamine, the sulphur analogue of the hallucinogen, psilocin, have been examined, and several new 4-benzyloxy- and 4-methoxy-benzo[b]thiophen derivatives have been obtained. In particular, 4-benzyloxy-3-methylbenzo[b]thiophen was prepared by a four-stage process from o-benzyloxyacetophenone. A successful synthesis of the required amine started from 4-methoxy-3-methylbenzo[b]thiophen-2-carboxylic acid, the crucial stage being the conversion of the derived 4-methoxy-3-methylbenzo[b]thiophen into 3-bromomethyl-4-methoxybenzo[b]thiophen. An attempted synthesis of 4-hydroxy-3-methylbenzo[b]thiophen from 3-methylthiophen is described.