sodium hydroxide; Raney Ni alloy in ethanol 1 h; Ambient temperature; Yield given;

1: Raney Ni alloy, 2 N aq. NaOH / ethanol / 1 h / Ambient temperature 2: 1.) oxygen, tetraphenylporphine, 2.) triphenylphosphine / 1.) CH2Cl2, -70 deg C, irradiation, 2 h, 2.) -70 deg C, 10 min View Scheme

2,2'-oxalyldi(o-sulfobenzimide) in acetonitrile 1) r.t., 15 min, 2) reflux, 30 min;