Acetonitrile → (2R,5R)-4-Benzyloxycarbonylmethyl-5-methoxymethyl-2-methyl-piperazine-1-carboxylic acid tert-butyl ester

HRID 1475285Notes

Reaction equation

HRID 1475285 reaction equation
[C:1]([O:5][C:6]([N:8]1[CH2:13][C@H:12]([CH2:14][O:15][CH3:16])[NH:11][CH2:10][C@H:9]1[CH3:17])=[O:7])([CH3:4])([CH3:3])[CH3:2].C(=O)([O-])[O-].[K+].[K+].C(#N)C.Br[CH2:28][C:29]([O:31][CH2:32][C:33]1[CH:38]=[CH:37][CH:36]=[CH:35][CH:34]=1)=[O:30]>C(Cl)(Cl)Cl>[C:1]([O:5][C:6]([N:8]1[CH2:13][C@H:12]([CH2:14][O:15][CH3:16])[N:11]([CH2:28][C:29]([O:31][CH2:32][C:33]2[CH:38]=[CH:37][CH:36]=[CH:35][CH:34]=2)=[O:30])[CH2:10][C@H:9]1[CH3:17])=[O:7])([CH3:4])([CH3:3])[CH3:2]

Participants

6

Reactant 4

HCID 6342AcetonitrileHCID 11430Potassium CarbonateHCID 62576Benzyl bromoacetateHCID 86723930tert-butyl (2R,5R)-5-(methoxymethyl)-2-methylpiperazine-1-carboxylate

Product 1

HCID 86723931(2R,5R)-4-Benzyloxycarbonylmethyl-5-methoxymethyl-2-methyl-piperazine-1-carboxylic acid tert-butyl esterYield 92%

Reagents, catalysts & solvents 1

HCID 6212ChloroformSolvent

Procedure

To a stirred suspension of (2R,5R)-5-methoxymethyl-2-methyl-piperazine-1-carboxylic acid tert-butyl ester (11 g, 45 mmol), potassium carbonate (6.79 g, 49.14 mmol) and acetonitrile (48 mL) was added benzyl bromoacetate (7.08 mL, 44.67 mmol) dropwise at ambient temperature. The reaction was stirred for 18 h at ambient temperature, then diluted with chloroform (150 mL), filtered and the filtrate concentrated. The crude oil was purified by column chromatography on silica gel (gradient elution, 0-70%, EtOAc/petrol), to give the title compound (16 g, 92%) as a pale yellow oil. 1H NMR (Me-d3-OD): 7.45-7.22 (5H, m), 5.21-5.12 (2H, m), 4.84 (2H, s), 4.16-4.03 (1H, m), 3.91 (1H, d), 3.62 (1H, d), 3.56-3.40 (2H, m), 3.31-3.19 (3H, m), 3.04-2.92 (1H, m), 2.80 (1H, dd), 2.68 (1H, dd), 1.48 (9H, s), 1.19 (3H, d).

Workup

  1. filtrationfiltered
  2. concentrationthe filtrate concentrated
  3. customThe crude oil was purified by column chromatography on silica gel (gradient elution, 0-70%, EtOAc/petrol)

Sources & evidence

ORD record
ord-aea7d0222dd54a8e816c08deb435f4ee
Source dataset
uspto-grants-2015_04
Patent number
US09018214B2

Reaction notes

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