Benzyl chloroformate → N2-((1,1-Dimethylethoxy)carbonyl)-N5-((phenylmethoxy)carbonyl)-D-ornithine

HRID 1518773Notes

Reaction equation

HRID 1518773 reaction equation
[NH:1]([C:10]([O:12][C:13]([CH3:16])([CH3:15])[CH3:14])=[O:11])[C@@H:2]([C:7]([OH:9])=[O:8])[CH2:3][CH2:4][CH2:5][NH2:6].Cl[C:18]([O:20][CH2:21][C:22]1[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1)=[O:19]>[OH-].[Na+]>[CH2:21]([O:20][C:18]([NH:6][CH2:5][CH2:4][CH2:3][C@@H:2]([NH:1][C:10]([O:12][C:13]([CH3:16])([CH3:15])[CH3:14])=[O:11])[C:7]([OH:9])=[O:8])=[O:19])[C:22]1[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1

Participants

4

Reactant 2

HCID 10387Benzyl chloroformateHCID 7019681(R)-5-Amino-2-((tert-butoxycarbonyl)amino)pentanoic acid

Product 1

HCID 7272030N2-((1,1-Dimethylethoxy)carbonyl)-N5-((phenylmethoxy)carbonyl)-D-ornithine

Reagents, catalysts & solvents 1

HCID 14798Sodium HydroxideSolvent2×

Procedure

To a solution of Boc-D-Orn-OH (0.50 g, 2.2 mmol) in aqueous NaOH (1M, 5 mL) at 0° C. was added benzyl chloroformate (0.37 mL, 2.6 mmol, 1.2 equiv) followed by aqueous NaOH (1M, 5 mL). After stirring for 2 hours at room temperature, the reaction mixture was poured to separatory funnel and extracted with ether. The aqueous layer was acidified to pH 3 with aqueous 10% citric acid and extracted with ethyl acetate. The combined organic layer was washed with brine, dried with Na2SO4, filtered and concentrated in vacuo to afford compound 3.2.1a (0.57 g, 72%) which was used for the next step without further purification. MS m/z (M+Na) 389.2. 1H NMR (400 MHz, DMSO-d6) 12.37 (br-s, 1H), 7.35-7.25 (m, 5H), 7.20 (t, J=5.31 Hz, 1H), 7.01 (d, J=8.02 Hz, 1H), 4.97 (s, 2H), 3.83-3.77 (m, 1H), 2.94 (dd, 2H), 1.67-1.56 (m, 1H), 1.53-1.37 (m, 3H), 1.34 (s, 9H).

Workup

  1. additionthe reaction mixture was poured to separatory funnel
  2. extractionextracted with ether
  3. extractionextracted with ethyl acetate
  4. washThe combined organic layer was washed with brine
  5. dry with materialdried with Na2SO4
  6. filtrationfiltered
  7. concentrationconcentrated in vacuo
  8. customto afford compound 3.2.1a (0.57 g, 72%) which
  9. customwas used for the next step without further purification

Sources & evidence

ORD record
ord-5b34a6e57ac9405d924313c2d4cf569f
Source dataset
uspto-grants-2015_07
Patent number
US09072696B2

Reaction notes

Loading…