2-(3-Chlorophenyl)-5,6,7,8-tetrahydroquinazolin-4-ol → 4-Chloro-2-(3-chlorophenyl)-5,6,7,8-tetrahydroquinazoline
Reaction equation
O(Cl)[Cl:2].[P+5].[Cl:5][C:6]1[CH:7]=[C:8]([C:12]2[NH:21][C:20](=O)[C:19]3[CH2:18][CH2:17][CH2:16][CH2:15][C:14]=3[N:13]=2)[CH:9]=[CH:10][CH:11]=1>>[Cl:2][C:20]1[C:19]2[CH2:18][CH2:17][CH2:16][CH2:15][C:14]=2[N:13]=[C:12]([C:8]2[CH:9]=[CH:10][CH:11]=[C:6]([Cl:5])[CH:7]=2)[N:21]=1Participants
3
Conditions
- Temperature
- 100 °C
Procedure
Phosphorus(V) oxychloride (17.6 g, 114.7 mmol) was slowly added to 2-(3-chlorophenyl)-5,6,7,8-tetrahydroquinazolin-4(3H)-one (2.2 g, 8.5 mmol) at 0° C. The reaction mixture was warmed to 100° C. and held at that temperature for 2 h. After this time, the mixture was cooled, quenched with saturated sodium hydroxide, and extracted with ethyl acetate. The combined organic layer was dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated. The residue was purified by column chromatography (silica, hexanes/dichloromethane) to afford the title compound (2.1 g, 23%) as a white solid. MW=279.16. 1H NMR (CDCl3, 300 MHz) δ 8.43-8.37 (m, 1H), 8.32-8.24 (m, 1H), 7.49-7.33 (m, 2H), 3.03-2.87 (m, 2H), 2.86-2.70 (m, 2H), 1.98-1.83 (m, 4H); APCI MS m/z 279 [M+H]+.