in quinoline soln. of porphyrin in quinoline heated to reflux (in the dark, under N2), addn. of VO(acac)2, stirred (2 h), monitored by UV; evapn., extn. (CH2Cl2), filtration (short alumina column), slow evapn.,addn. of MeOH, crystn.;

in neat (no solvent) under N2 or Ar; heated for 45 min at 240°C in a test tube; the solid is dissolved in CH2Cl2, filtd., the soln. is chromd., the solid is recrystd. (benzene/methanol);

O2 in toluene toluene soln. exposing to air at room temp.; identified by IR spectrum;

O2 in neat (no solvent, solid phase) exposing to air at room temp.; identified by IR spectrum;