1,4-Dioxane hydrochloride → 4-{2-[2-(Acetylamino)-1,3-thiazol-4-yl]ethyl}benzyl hydrazinecarboxylate hydrochloride
Reaction equation
[NH:1]([C:10]([O:12][CH2:13][C:14]1[CH:19]=[CH:18][C:17]([CH2:20][CH2:21][C:22]2[N:23]=[C:24]([NH:27][C:28](=[O:30])[CH3:29])[S:25][CH:26]=2)=[CH:16][CH:15]=1)=[O:11])[NH:2]C(OC(C)(C)C)=O.O1CCOCC1.[ClH:37]>ClCCl>[ClH:37].[NH:1]([C:10]([O:12][CH2:13][C:14]1[CH:15]=[CH:16][C:17]([CH2:20][CH2:21][C:22]2[N:23]=[C:24]([NH:27][C:28](=[O:30])[CH3:29])[S:25][CH:26]=2)=[CH:18][CH:19]=1)=[O:11])[NH2:2]Participants
4
Procedure
To a suspension of 4-{2-[2-(acetylamino)-1,3-thiazol-4-yl]ethyl}benzyl tert-butyl hydrazine-1,2-dicarboxylate (203.0 mg, 0.467 mmol) in anhydrous dichloromethane (2.3 ml) was added 4M hydrogen chloride dioxane solution (2.3 ml, 9.2 mmol). After stirring at room temperature for 2.5 hr, the mixture was concentrated under reduced pressure. Ethyl acetate was added to the concentrated residue, and the mixture was concentrated again under reduced pressure. This operation was performed 3 times to remove hydrogen chloride gas azeotropically. The residue was suspended in ethyl acetate and filtered. The filtered product was washed with ethyl acetate and dried under reduced pressure to give the title compound (179.3 mg, quantitative) as a white solid.