Ethyl cyanoacetate → tert-Butyl 4-(cyanoacetyl)piperazine-1-carboxylate

HRID 1726021Notes

Reaction equation

HRID 1726021 reaction equation
[C:1]([O:5][C:6]([N:8]1[CH2:13][CH2:12][NH:11][CH2:10][CH2:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2].[C:14]([CH2:16][C:17](OCC)=[O:18])#[N:15]>C1(C)C=CC=CC=1>[C:14]([CH2:16][C:17]([N:11]1[CH2:12][CH2:13][N:8]([C:6]([O:5][C:1]([CH3:4])([CH3:2])[CH3:3])=[O:7])[CH2:9][CH2:10]1)=[O:18])#[N:15]

Participants

4

Reactant 2

HCID 7764Ethyl cyanoacetateHCID 143452tert-Butyl piperazine-1-carboxylate

Product 1

HCID 18946315tert-Butyl 4-(cyanoacetyl)piperazine-1-carboxylateYield 36.3%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

A mixture of 1-tert-butoxycarbonylpiperazine (7.44 g, 40 mmol) and ethyl cyanoacetate (8.53 mL, 80 mmol) was gently stirred in 20 mL of toluene at 90° C. for 2 days. The mixture was concentrated and purified by silica gel column chromatography, eluting with 30% ethyl acetate in n-hexane to provide the title compound (3.68 g). MS (ESI(−)) m/e 252 (M−H)−; 1H NMR (300 MHz, DMSO-d6) δ 3.41 (m, 4H), 3.27-3.35 (m, 4H), 2.72 (m, 2H), 2.38 (m, 2H), 1.41 (s, 9H).

Workup

  1. concentrationThe mixture was concentrated
  2. custompurified by silica gel column chromatography
  3. washeluting with 30% ethyl acetate in n-hexane

Sources & evidence

ORD record
ord-6bd9e1d6e9ff42ecb6e30704abd7d4bb
Source dataset
uspto-grants-2009_02
Patent number
US07491718B2

Reaction notes

Loading…