1,1'-Thiocarbonyldiimidazole → 4-(4-Isothio-cyanatophenyl)-1-piperazinecarboxylic acid, 1,1-dimethylethyl ester
反応式
[NH2:1][C:2]1[CH:7]=[CH:6][C:5]([N:8]2[CH2:13][CH2:12][N:11]([C:14]([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[O:15])[CH2:10][CH2:9]2)=[CH:4][CH:3]=1.[C:21](N1C=CN=C1)(N1C=CN=C1)=[S:22]>CN(C)C=O>[N:1]([C:2]1[CH:7]=[CH:6][C:5]([N:8]2[CH2:13][CH2:12][N:11]([C:14]([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[O:15])[CH2:10][CH2:9]2)=[CH:4][CH:3]=1)=[C:21]=[S:22]参加物
4
実験手順
A solution of 4-(4-aminophenyl)-1-piperazinecarboxylic acid, 1,1-dimethylethyl ester (15 g, 54.1 mmol) (from Step B above) in N,N-dimethylformamide (120 mL) was added dropwise to a cooled (−15° C.) solution of 1,1′-thiocarbonyldiimidazole (9.66 g, 54.2 mmol) (Aldrich) in N,N-dimethylformamide (40 mL). After the addition was complete, the cooling bath was removed and the solution was stirred for 1 h. The mixture was poured into ice-water (1 L), stirred for 30 minutes, and extracted with diethyl ether. The combined extracts were dried over Na2SO4, and evaporated in vacuo to provide 4-(4-isothio-cyanatophenyl)-1-piperazinecarboxylic acid, 1,1-dimethylethyl ester (18 g, 94%).