Yield given. Multistep reaction;

oxygen; 5,15,10,20-tetraphenylporphyrin in dichloromethane T=-10 - -5°C; 0.5 h; Irradiation; Yields of byproduct given;

titanium(IV) isopropylate; 4 A molecular sieve; oxygen; 5,15,10,20-tetraphenylporphyrin 1.) CH2Cl2, -10 to -5 deg C, irradiation, 2.5 h, 2.) 0 deg C, 6 h; Yield given. Multistep reaction;