Synthesis of 9,10-dihydrophenanthrenes including orchinol methyl ether

Abstract

Reduction of 2-phenylindole gave the dihydro derivative which was hydrogenolysed to give bibenzyl-2-amine. The latter was best converted into 9,10-dihydrophenanthrene by decomposition of the derived azosulphone. Several methoxydihydrophenanthrenes, including orchinol methyl ether, were prepared by this route.     Conversion of dihydrophenanthrenes into phenanthrenes may be conveniently effected by benzylic bromination followed by dehydrobromination.