Photochemical reactions of cyclic saturated a-diketones in toluene or p-xylene produce 1: l adducts as major products and smaller amounts of reduced diketone and bibenzyls, as expected from previous work. In addition, reaction of BOD gave 2% of the decarbonylation product, p-methylbenzyl cyclohexyl ketone; reaction of camphorquinone gave a mixture of decarbonylation products (10% total) including saturated and unsaturated monoketones. ...