P,P-Diphenylphosphinic azide → 2H,3H-[1,2]thiazolo[5,4-b]pyridin-3-one

Reaction equation

C1(P([N:15]=[N+]=[N-])(C2C=CC=CC=2)=O)C=CC=CC=1.[SH:18][C:19]1[N:27]=[CH:26][CH:25]=[CH:24][C:20]=1[C:21](O)=[O:22]>N1C=CC=CC=1.C(N(CC)CC)C>[S:18]1[C:19]2=[N:27][CH:26]=[CH:25][CH:24]=[C:20]2[C:21](=[O:22])[NH:15]1

Participants

Procedure

To a solution of diphenylphosphoryl azide (39.41 g, 0.139 mol) in pyridine (160 ml) and triethylamine (19 ml) was added 2-mercaptonicotinic acid (21.57 g, 0.139 mol) portionwise at 0° C. The reaction mixture was stirred overnight at room temperature and afterwards concentrated in vacuo. Ethanol (15 ml) was added at 30° C. to the crude product. Filtration at room temperature afforded a yellow solid which was washed with ethanol (15 ml) and dried in vacuo (10 mbar). 17.04 g (89%) of the title compound were obtained as light yellow solid.