Phosphorus oxychloride → 4-Chloro-6-(5-trifluoromethyl-1,3,4-oxadiazol-2-yl)quinazoline
Reaction equation
[F:1][C:2]([F:20])([F:19])[C:3]1[O:7][C:6]([C:8]2[CH:9]=[C:10]3[C:15](=[CH:16][CH:17]=2)[N:14]=[CH:13][NH:12][C:11]3=O)=[N:5][N:4]=1.P(Cl)(Cl)([Cl:23])=O>C(N(CC)CC)C>[Cl:23][C:11]1[C:10]2[C:15](=[CH:16][CH:17]=[C:8]([C:6]3[O:7][C:3]([C:2]([F:20])([F:19])[F:1])=[N:4][N:5]=3)[CH:9]=2)[N:14]=[CH:13][N:12]=1Participants
4
Procedure
6-(5-Trifluoromethyl-1,3,4-oxadiazol-2-yl)quinazolin-4-one (0.79 g) was treated with phosphorus oxychloride (18 ml) and triethylamine (8 ml) at reflux under N2 for 2 hours. The mixture was concentrated in vacuo and the residue azeotroped with toluene. This was then taken up in ethyl acetate and washed with 5% sodium bicarbonate and saturated brine, dried over magnesium sulphate and concentrated in vacuo to give the title compound (0.76 g) as an orange solid; δH CDCl3 9.17(1H,s), 9.05 (1H,d), 8.69(1H,dd), 8.30(1H,d).