Lithium Hydroxide → tert-Butyloxycarbonyl-glycylphenylalanine

HRID 1903367Notes

Reaction equation

HRID 1903367 reaction equation
C[O:2][C:3](=[O:24])[C@H:4]([CH2:17][C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1)[NH:5][C:6](=[O:16])[CH2:7][NH:8][C:9]([O:11][C:12]([CH3:15])([CH3:14])[CH3:13])=[O:10].[Li+].[OH-]>CO>[C:12]([O:11][C:9]([NH:8][CH2:7][C:6]([NH:5][C@H:4]([C:3]([OH:24])=[O:2])[CH2:17][C:18]1[CH:19]=[CH:20][CH:21]=[CH:22][CH:23]=1)=[O:16])=[O:10])([CH3:15])([CH3:13])[CH3:14]

Participants

4

Reactant 2

HCID 3939Lithium HydroxideHCID 13036549HCID 13036549, compound

Product 1

HCID 151217tert-Butyloxycarbonyl-glycylphenylalanine

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

t-Boc-gly-phe-OCH3, 6a, (9.2 g, 2.7 ×10-2 mole), 1M aqueous LiOH (30 ml, 3.0 ×10-2 mole), and methanol (100 ml) are stirred at room temperature for 2 hours. Most of the methanol is evaporated. The concentrate is diluted with water (10 ml) and transferred to a separatory funnel. The mixture is then acidified with 1M aqueous HCl (50 ml) and the aqueous acidic mixture subsequently extracted with CHCl3 (4 times). The combined CHCl3 extracts are washed with saturated aqueous NaCl before being dried over Na2SO4. Filtration of the drying agent and evaporation of the filtrate gives a foam which when triturated with Et2O/hexane affords 7a as a colorless solid which crystallizes from ethyl acetate/hexane as colorless needles: 6.3 g (71%), m.p. 138-141° C.

Workup

  1. customMost of the methanol is evaporated
  2. additionThe concentrate is diluted with water (10 ml)
  3. customtransferred to a separatory funnel
  4. extractionthe aqueous acidic mixture subsequently extracted with CHCl3 (4 times)
  5. washThe combined CHCl3 extracts are washed with saturated aqueous NaCl
  6. dry with materialbefore being dried over Na2SO4
  7. filtrationFiltration of the drying agent and evaporation of the filtrate
  8. customgives a foam which when
  9. customtriturated with Et2O/hexane

Sources & evidence

ORD record
ord-da280d9d12614f86a9d99d51e00fbb6c
Source dataset
uspto-grants-1984_03
Patent number
US04435571

Reaction notes

Loading…