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

HRID 1677736Notes

Reaction equation

HRID 1677736 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>C(Cl)Cl>[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 solution of 1-Boc-piperazine (25 g, 0.13 mol) in anhydrous DCM (500 mL) at 0° C. 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) slowly over a period of 30 min. The reaction mixture was stirred at RT for 16 hours and washed with a 10% aqueous solution of sodium bicarbonate, water and brine. The organic layer was dried and the solvent was removed under vacuum. The residue was purified by chromatography using chloroform/methanol (95/5) as eluent to afford 15 g (57%) of the title compound as a solid. TLC—Chloroform/methanol (9/1): Rf=0.7.

Workup

  1. washwashed with a 10% aqueous solution of sodium bicarbonate, water and brine
  2. customThe organic layer was dried
  3. customthe solvent was removed under vacuum
  4. customThe residue was purified by chromatography

Sources & evidence

ORD record
ord-01c71d38bce4456eb3292c62f9fb49da
Source dataset
uspto-grants-2011_08
Patent number
US08008302B2

Reaction notes

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