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 ...