Pyridine → (S)-4-benzyl-2-(2-methanesulfonyloxy-ethyl)piperazine-1-carboxylic acid tert-butyl ester

HRID 131400Notes

Reaction equation

HRID 131400 reaction equation
[C:1]([O:5][C:6]([N:8]1[CH2:13][CH2:12][N:11]([CH2:14][C:15]2[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=2)[CH2:10][C@@H:9]1[CH2:21][CH2:22][OH:23])=[O:7])([CH3:4])([CH3:3])[CH3:2].N1C=CC=CC=1.[CH3:30][S:31](Cl)(=[O:33])=[O:32]>ClCCl.C(=O)(O)[O-].[Na+]>[NH3:8].[CH3:1][OH:5].[C:1]([O:5][C:6]([N:8]1[CH2:13][CH2:12][N:11]([CH2:14][C:15]2[CH:16]=[CH:17][CH:18]=[CH:19][CH:20]=2)[CH2:10][C@@H:9]1[CH2:21][CH2:22][O:23][S:31]([CH3:30])(=[O:33])=[O:32])=[O:7])([CH3:4])([CH3:3])[CH3:2]

Participants

7

Reactant 3

HCID 1049PyridineHCID 31297Methanesulfonyl chlorideHCID 15406045(S)-4-Benzyl-2-(2-hydroxyethyl)piperazine-1-carboxylic acid tert-butyl ester

Product 2

HCID 21705897Ammonia methanolYield 5%HCID 86604576(S)-4-benzyl-2-(2-methanesulfonyloxy-ethyl)piperazine-1-carboxylic acid tert-butyl esterYield 123.5%

Reagents, catalysts & solvents 2

HCID 6344DichloromethaneSolvent3×HCID 516892Sodium BicarbonateSolvent

Procedure

To a solution of (S)-4-benzyl-2-(2-hydroxyethyl)piperazine-1-carboxylic acid tert-butyl ester (4.87 g, 15.2 mmol) in dichloromethane (200 mL), add pyridine (1.84 mL, 22.8 mmol) followed by methanesulfonyl chloride (1.29 mL, 16.7 mmol). Stir at room temperature overnight, then dilute with saturated aqueous sodium bicarbonate. Extract three times with dichloromethane; dry combined organic extracts over sodium sulfate, filter and concentrate in vacuo to give a brown residue. Redissolve residue in dichloromethane and apply to a plug of silica gel. Wash plug with 5% 2N ammonia-methanol in dichloromethane to obtain (S)-4-benzyl-2-(2-methanesulfonyloxy-ethyl)piperazine-1-carboxylic acid tert-butyl ester (3.74 g, 62%) as a yellow-brown thick oil.

Workup

  1. extractionExtract three times with dichloromethane
  2. customdry
  3. filtrationfilter
  4. concentrationconcentrate in vacuo
  5. customto give a brown residue

Sources & evidence

ORD record
ord-7515a520812d4d84adc1e86c622dea02
Source dataset
uspto-grants-2008_06
Patent number
US07384934B2

Reaction notes

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