Cyanogen Bromide → tert-Butyl 4-cyanopiperazine-1-carboxylate

HRID 888201Notes

Reaction equation

HRID 888201 reaction equation
[C:1]([N:8]1[CH2:13][CH2:12][NH:11][CH2:10][CH2:9]1)([O:3][C:4]([CH3:7])([CH3:6])[CH3:5])=[O:2].[N:14]#[C:15]Br>ClCCl>[C:15]([N:11]1[CH2:10][CH2:9][N:8]([C:1]([O:3][C:4]([CH3:7])([CH3:6])[CH3:5])=[O:2])[CH2:13][CH2:12]1)#[N:14]

Participants

4

Reactant 2

HCID 10476Cyanogen BromideHCID 143452tert-Butyl piperazine-1-carboxylate

Product 1

HCID 14068968tert-Butyl 4-cyanopiperazine-1-carboxylateYield 57%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

To a cold (0° C.) solution of 1-Boc-piperazine (25 g, 0.13 mol) in dry dichloromethane (500 mL) was added TEA (52 mL, 0.40 mol) followed by a solution of cyanogen bromide (28.5 g, 0.27 mol) in anhydrous DCM (250 mL) over a period of 30 min. The reaction mixture was stirred at RT for 16 hours, then washed with a 10% aq. solution of sodium bicarbonate, water, brine and dried. The solvent was removed under vacuum and the residue was purified by flash chromatography (CHCl3/MeOH 95/5) to give 15 g (57%) of The title compound as a solid. TLC-CHCl3/MeOH (9/1): Rf=0.7.

Workup

  1. washwashed with a 10% aq. solution of sodium bicarbonate, water, brine
  2. customdried
  3. customThe solvent was removed under vacuum
  4. customthe residue was purified by flash chromatography (CHCl3/MeOH 95/5)

Sources & evidence

ORD record
ord-2d2acc75b0f24859a0a4e69f05d38d1e
Source dataset
uspto-grants-2012_08
Patent number
US08247437B2

Reaction notes

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