Diethyl Ether → Tert-butyl 4-(6-chloropyrazin-2-YL)piperazine-1-carboxylate

HRID 1296618Notes

Reaction equation

HRID 1296618 reaction equation
[N:1]1([C:7]([O:9][C:10]([CH3:13])([CH3:12])[CH3:11])=[O:8])[CH2:6][CH2:5][NH:4][CH2:3][CH2:2]1.[Cl:14][C:15]1[CH:20]=[N:19][CH:18]=[C:17](Cl)[N:16]=1.C([O-])([O-])=O.[K+].[K+].CCOCC>C(#N)C>[Cl:14][C:15]1[N:16]=[C:17]([N:4]2[CH2:5][CH2:6][N:1]([C:7]([O:9][C:10]([CH3:13])([CH3:12])[CH3:11])=[O:8])[CH2:2][CH2:3]2)[CH:18]=[N:19][CH:20]=1

Participants

6

Reactant 4

HCID 3283Diethyl EtherHCID 11430Potassium CarbonateHCID 785042,6-DichloropyrazineHCID 143452tert-Butyl piperazine-1-carboxylate

Product 1

HCID 18186946Tert-butyl 4-(6-chloropyrazin-2-YL)piperazine-1-carboxylateYield 90%

Reagents, catalysts & solvents 1

HCID 6342AcetonitrileSolvent

Conditions

Temperature
65 °C

Procedure

A mixture of tert-butyl 1-piperazinecarboxylate (5.07 g, 27.2 mmol), 2,6-dichloropyrazine (3.38 g, 22.7 mmol), and K2CO3 (4.09 g, 30.0 mmol) in acetonitrile (20 mL) was stirred at 65° C. for 12.5 h and for a further 15 h at room temperature. Ether was added and the suspension was filtered. Concentration in vacuo fumished the crude product as an oil that crystallized upon standing. Purification by chromatography on silica gel using ethyl acetate/n-hexane (6:4) as eluent gave 6.1 g (90%) of the title compound as a solid. HRMS m/z calcd for C13H19ClN4O2 (M)+ 298.1197, found 298.1211. Anal. (C13H19ClN4O2) C, H, N.

Workup

  1. filtrationthe suspension was filtered
  2. concentrationConcentration in vacuo
  3. customcrystallized
  4. customPurification by chromatography on silica gel

Sources & evidence

ORD record
ord-e7e2fb7935bf4a178c5e0b4cc44e63b7
Source dataset
uspto-grants-2007_07
Patent number
US07247633B2

Reaction notes

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