Hydrogen chloride-ethyl acetate → Hydrochloric Acid

Reaction equation

C(OC([NH:8][C@@H:9]([CH3:33])[C:10]([NH:12][C@@H:13]([CH2:24][C:25]1[CH:30]=[CH:29][C:28]([O:31][CH3:32])=[CH:27][CH:26]=1)[C:14]([O:16][CH2:17][C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1)=[O:15])=[O:11])=O)(C)(C)C.[ClH:34].CCOC(C)=O>>[NH2:8][C@@H:9]([CH3:33])[C:10]([NH:12][C@@H:13]([CH2:24][C:25]1[CH:26]=[CH:27][C:28]([O:31][CH3:32])=[CH:29][CH:30]=1)[C:14]([O:16][CH2:17][C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1)=[O:15])=[O:11].[ClH:34]

Participants

Reactant 2

HCID 21866389Hydrogen chloride-ethyl acetate

HCID 59254431(S)-benzyl 2-((S)-2-((tert-butoxycarbonyl)amino)propanamido)-3-(4-methoxyphenyl)propanoate

Product 2

HCID 313Hydrochloric Acid

HCID 130394596(S)-benzyl 2-((S)-2-aminopropanamido)-3-(4-methoxyphenyl)propanoate

Procedure

A solution of (S)-benzyl 2-((S)-2-((tert-butoxycarbonyl)amino)propanamido)-3-(4-methoxyphenyl)propanoate (29.0 g, 63.6 mmol) in 3 N HCl-EtOAc (150 mL) was stirred for 1 h at ambient temperature. The mixture was concentrated and the residue was washed with petroleum ether (100 mL) to afford (S)-benzyl 2-((S)-2-aminopropanamido)-3-(4-methoxyphenyl)propanoate as an HCl salt (quant.), which was used directly in the next step without further purification.