C(OC([N:8]1[CH2:13][CH2:12][N:11]([C:14]2[CH:19]=[CH:18][C:17]([C:20]#[N:21])=[C:16]([F:22])[CH:15]=2)[CH2:10][CH2:9]1)=O)(C)(C)C.Cl>CO>[F:22][C:16]1[CH:15]=[C:14]([N:11]2[CH2:10][CH2:9][NH:8][CH2:13][CH2:12]2)[CH:19]=[CH:18][C:17]=1[C:20]#[N:21]A solution of 4-(4-cyano-3-fluoro-phenyl)-piperazine-1-carboxylic acid tert-butyl ester (6.97 g, 22.83 mmol) in methanol (250 mL) was saturated with HCl gas and stirred at ambient temperature overnight. The reaction was concentrated, saturated sodium bicarbonate (250 mL) was added and the slurry was stirred for 1 hour. The resulting solid was filtered off, rinsed well with water, air dried then evacuated overnight. As water was removed from the solid, it turned to a milky yellow solid which slowly solidified to give 2-fluoro-4-piperazin-1-yl-benzonitrile as a waxy solid (3.84 g, 82%).
Wird geladen…