Intermolecular Friedel-Crafts acylation of various substituted alkyl-or alkoxybenzenes with oxalyl chloride using carbon disulfide as solvent gave rise to the benzils la-k. Subsequent intramolecular oxidative coupling with either thallium (II1) oxide/trifluoroacetic acid or vanadium (V) oxyfluoride/boron trifluoride diethyl etherate resulted in the corresponding phenanthrene-9, lO-diones 2a-d. It has been shown that oxygen functionalities at the 3, 3', ...