Experimental Section Ozonation of Tetraphenylcyclopentadienone (1). Ten millimoles of ozone was passed into a solution of 10 mmol of 1 (Aldrich, mp 217-220" C) in 100 mL of dichloromethane at-78" C by the usual procedure (earlier papers of senior author). The ozone absorption was generally quantitative and the reaction mixture changes from deep purple to light gold. The solvent wm removed via a rotary evaporator and the red-gold ...
