ozone in dichloromethane solvent ozonization at -78°C for 1 h, Bi-compd. soln. addn. to ozonized solvent in 1 portion, suspn. allowing to warm to room temp. (30 min), filtration (Celite), filtrate evapn. (reduced pressure); residue chromy. (silica gel, CH2Cl2/EtOH 1:0 to 50:1); elem. anal.;

1: brine / chloroform 2: ozone / dichloromethane View Scheme

1: 2-Hydroxypyridine With potassium tert-butylate in tetrahydrofuran T=20°C; 0.166667 h; 2: tris(2-methoxyphenyl)bismuth dichloride in tetrahydrofuran 3 h; Heating;

1: KO-t-Bu / dichloromethane 2: dichloromethane 3: copper(II) bis(trifluoromethanesulfonate) / dichloromethane View Scheme

in dichloromethane Bi-salt soln. addn. to Ag2O suspn., suspn. refluxing in dark for 4 h, mixt. filtration (Celite), filtrate evapn. (reduced pressure); recrystn. (CH2Cl2/EtOAc 1:5); elem. anal.;

1: 2-Hydroxypyridine With potassium tert-butylate in tetrahydrofuran T=20°C; 0.166667 h; 2: tris(2-methoxyphenyl)bismuth dichloride in tetrahydrofuran 3 h; Heating;