Benzyl Alcohol → Boc-DTrp-OBzl

HRID 1906

Reaction equation

HRID 1906 reaction equation
[C:1]([O:5][C:6]([NH:8][C@@H:9]([C:20]([OH:22])=[O:21])[CH2:10][C:11]1[C:19]2[C:14](=[CH:15][CH:16]=[CH:17][CH:18]=2)[NH:13][CH:12]=1)=[O:7])([CH3:4])([CH3:3])[CH3:2].[CH2:23](O)[C:24]1[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=1.Cl.CN(C)CCCN=C=NCC.O>C(Cl)Cl.CN(C)C1C=CN=CC=1>[CH2:23]([O:21][C:20](=[O:22])[C@@H:9]([CH2:10][C:11]1[C:19]2[C:14](=[CH:15][CH:16]=[CH:17][CH:18]=2)[NH:13][CH:12]=1)[NH:8][C:6]([O:5][C:1]([CH3:4])([CH3:2])[CH3:3])=[O:7])[C:24]1[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=1

Participants

7

Reactant 4

HCID 244Benzyl AlcoholHCID 962WaterHCID 111050N-((tert-Butoxy)carbonyl)-D-tryptophanHCID 27239391,3-Propanediamine, N'-(ethylcarbonimidoyl)-N,N-dimethyl-, monohydrochloride

Product 1

HCID 10739405Boc-DTrp-OBzl

Reagents, catalysts & solvents 2

HCID 142844-(Dimethylamino)pyridineCatalystHCID 6344DichloromethaneSolvent

Procedure

Finely divided t-butoxycarbonyl-D-tryptophan (3 g, 10 mmol) was suspended in methylene chloride and benzyl alcohol (1.08 mL, 10 mmol) and 4-dimethylaminopyridine (0.12 g, 1 mmol) were added and stirred at room temperature. Solid 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (1.92 g, 10 mmol) was then added in three roughly equal portions over 5 minutes. The reaction mixture was stirred for 3 hours at room temperature during which time the reaction mixture became a homogeneous solution. The reaction mixture was poured into water (100 mL) and extracted with methylene chloride (2×50 mL). The combined methylene chloride layers were washed with 5% aqueous citric acid solution (100 mL) and 5% aqueous sodium bicarbonate solution (100 mL). The resulting methylene chloride layer was dried over magnesium sulfate, filtered and evaporated under vaccum to give an off-white solid. This solid material was chromatographed on silica gel using ethyl acetate/hexanes (2:3 v/v) as eluant. This afforded 3.56 g (91%) of the desired benzyl ester as a white amorphous powder.

Workup

  1. stirringThe reaction mixture was stirred for 3 hours at room temperature during which time the reaction mixture
  2. extractionextracted with methylene chloride (2×50 mL)
  3. washThe combined methylene chloride layers were washed with 5% aqueous citric acid solution (100 mL) and 5% aqueous sodium bicarbonate solution (100 mL)
  4. dry with materialThe resulting methylene chloride layer was dried over magnesium sulfate
  5. filtrationfiltered
  6. customevaporated under vaccum
  7. customto give an off-white solid
  8. customThis solid material was chromatographed on silica gel

Sources & evidence

ORD record
ord-8d15441bff9244cf8bac899003f74801
Source dataset
uspto-grants-1998_03
Patent number
US05726319

Linked notes

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