Ammonium Chloride → 2,2-Bis(tert-butoxycarbonylamino)-5-(1-ethoxycarbonyl-ethylamino)-pentanoic acid benzyl ester

HRID 79705Notes

Reaction equation

HRID 79705 reaction equation
[C:1](O[BH-](OC(=O)C)OC(=O)C)(=O)[CH3:2].[Na+].[CH2:15]([O:22][C:23](=[O:45])[C:24]([NH:37][C:38]([O:40][C:41]([CH3:44])([CH3:43])[CH3:42])=[O:39])([NH:29][C:30]([O:32][C:33]([CH3:36])([CH3:35])[CH3:34])=[O:31])[CH2:25]CC=O)[C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1.Cl.[CH2:47]([O:49][C:50](=[O:54])[C@H:51]([CH3:53])[NH2:52])[CH3:48].[Cl-].[NH4+]>ClCCl>[CH2:15]([O:22][C:23](=[O:45])[C:24]([NH:29][C:30]([O:32][C:33]([CH3:36])([CH3:34])[CH3:35])=[O:31])([NH:37][C:38]([O:40][C:41]([CH3:42])([CH3:43])[CH3:44])=[O:39])[CH2:25][CH2:1][CH2:2][NH:52][CH:51]([C:50]([O:49][CH2:47][CH3:48])=[O:54])[CH3:53])[C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1

Participants

6

Reactant 4

HCID 25517Ammonium ChlorideHCID 2724356L-Alanine, ethyl ester, hydrochloride (1:1)HCID 5049666Sodium triacetoxyborohydrideHCID 866488762,2-Bis(tert-butoxycarbonylamino)-5-oxo-pentanoic acid benzyl ester

Product 1

HCID 866488772,2-Bis(tert-butoxycarbonylamino)-5-(1-ethoxycarbonyl-ethylamino)-pentanoic acid benzyl esterYield 41.8%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

Sodium triacetoxyborohydride (5 g, 23.5 mmol) was added to a solution of 2,2-bis(tert-butoxycarbonylamino)-5-oxo-pentanoic acid benzyl ester (3.34 g, 7.9 mmol) and alanine ethyl ester hydrochloride (3.62 g, 23.5 mmol) in dichloromethane (30 mL). After 1 hour saturated ammonium chloride (10 mL) was added and the mixture was stirred for 5 minutes. The aqueous phase was extracted with dichloromethane (2×15 mL), and the combined organic phases were dried over sodium sulfate, filtered and the solvent was removed under reduced pressure. The resulting residue was subjected to flash chromatography with eluent of(10% methanol in ethyl acetate) and hexane. The product-containing fractions were combined and the solvent was removed under reduced pressure to provide 2,2-bis(tert-butoxycarbonylamino)-5-(1-ethoxycarbonyl-ethylamino)-pentanoic acid benzyl ester (1.7 g, 3.3 mmol, 41%). C27H42N2O8 calculated 522.3 observed [M+1]+ 523.3; rt=2.08 min.

Workup

  1. extractionThe aqueous phase was extracted with dichloromethane (2×15 mL)
  2. dry with materialthe combined organic phases were dried over sodium sulfate
  3. filtrationfiltered
  4. customthe solvent was removed under reduced pressure
  5. customthe solvent was removed under reduced pressure

Sources & evidence

ORD record
ord-8cb48817f4f447f590d4c5e920553bb5
Source dataset
uspto-grants-2014_09
Patent number
US08841278B2

Reaction notes

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