Dimethyl Sulfoxide → (2S,5R)-2,5-Dimethyl-4-(5-nitro-pyridin-2-yl)-piperazine-1-carboxylic acid tert-butyl ester

HRID 1504314Notes

Reaction equation

HRID 1504314 reaction equation
Cl[C:2]1[CH:7]=[CH:6][C:5]([N+:8]([O-:10])=[O:9])=[CH:4][N:3]=1.[C:11]([O:15][C:16]([N:18]1[CH2:23][C@@H:22]([CH3:24])[NH:21][CH2:20][C@@H:19]1[CH3:25])=[O:17])([CH3:14])([CH3:13])[CH3:12].C(=O)([O-])[O-].[K+].[K+].CS(C)=O>>[C:11]([O:15][C:16]([N:18]1[CH2:23][C@@H:22]([CH3:24])[N:21]([C:2]2[CH:7]=[CH:6][C:5]([N+:8]([O-:10])=[O:9])=[CH:4][N:3]=2)[CH2:20][C@@H:19]1[CH3:25])=[O:17])([CH3:14])([CH3:12])[CH3:13]

Participants

5

Reactant 4

HCID 679Dimethyl SulfoxideHCID 11430Potassium CarbonateHCID 783082-Chloro-5-nitropyridineHCID 11745988(2S,5R)-1-Boc-2,5-dimethylpiperazine

Product 1

HCID 86682794(2S,5R)-2,5-Dimethyl-4-(5-nitro-pyridin-2-yl)-piperazine-1-carboxylic acid tert-butyl esterYield 81.4%

Procedure

A mixture of 2-chloro-5-nitropyridine (1.0 g, 6.3 mmol), (2S,5R)-2,5-dimethyl-piperazine-1-carboxylic acid tert-butyl ester (1.4 g, 6.3 mmol), and potassium carbonate (1.7 g, 13 mmol) was stirred in DMSO (5.0 mL, 70 mmol) at 100° C. overnight. The reaction mixture was filtered thru a silica gel pad, which was washed with EtOAc (200 mL). The filtrate was washed with water (2×10 mL), concentrated, and purified by silica gel chromatography (eluted with ethyl acetate/hexane=0 to 80%) to give the title intermediate (1.724 g, 81% yield) as a yellow solid.

Workup

  1. filtrationThe reaction mixture was filtered thru a silica gel pad, which
  2. washwas washed with EtOAc (200 mL)
  3. washThe filtrate was washed with water (2×10 mL)
  4. concentrationconcentrated
  5. custompurified by silica gel chromatography (eluted with ethyl acetate/hexane=0 to 80%)

Sources & evidence

ORD record
ord-ae36bdcf0da7485889afa429fe5ea7ea
Source dataset
uspto-grants-2015_12
Patent number
US09212168B2

Reaction notes

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