Dichloromethane → 1-(2-Chloro-6-nitrophenyl)piperazine

HRID 2220530Notes

Reaction equation

HRID 2220530 reaction equation
C(OC([N:8]1[CH2:13][CH2:12][N:11]([C:14]2[C:19]([N+:20]([O-:22])=[O:21])=[CH:18][CH:17]=[CH:16][C:15]=2[Cl:23])[CH2:10][CH2:9]1)=O)(C)(C)C.C(Cl)Cl>FC(F)(F)C(O)=O>[Cl:23][C:15]1[CH:16]=[CH:17][CH:18]=[C:19]([N+:20]([O-:22])=[O:21])[C:14]=1[N:11]1[CH2:12][CH2:13][NH:8][CH2:9][CH2:10]1

Participants

4

Reactant 2

HCID 6344DichloromethaneHCID 587677041-Boc-4-(2-chloro-6-nitrophenyl)piperazine

Product 1

HCID 27714081-(2-Chloro-6-nitrophenyl)piperazineYield 95.3%

Reagents, catalysts & solvents 1

HCID 6422Trifluoroacetic acidSolvent

Procedure

4-(2-Chloro-6-nitro-phenyl)-piperazine-1-carboxylic acid tert-butyl ester (1.87 g, 5.47 mmol) was dissolved in trifluoroacetic acid (5.0 mL) and CH2Cl2 (5.0 mL) and allowed to stir for 2 h. The reaction mixture was concentrated, diluted with EtOAc, and washed with saturated aq. NaHCO3. The organic layer was dried over Na2SO4, concentrated and purified by column chromatography (silica, 100% CH2Cl2) to afford 1-(2-chloro-6-nitro-phenyl)-piperazine (1.26 g, 95%). MS (electrospray): exact mass calculated for C10H12ClN3O2, 241.1; m/z found, 242.1 [M+H]+. 1H NMR (400 MHz, CDCl3): 7.54 (dd, J=8.2, 1.6 Hz, 1H), 7.49 (dd, J=8.2, 1.6 Hz, 1H), 7.10 (t, J=8.2 Hz, 1H), 3.08 (br s, 4H), 2.99 (br s, 4H), 2.07-2.12 (m, 1H).

Workup

  1. concentrationThe reaction mixture was concentrated
  2. additiondiluted with EtOAc
  3. washwashed with saturated aq. NaHCO3
  4. dry with materialThe organic layer was dried over Na2SO4
  5. concentrationconcentrated
  6. custompurified by column chromatography (silica, 100% CH2Cl2)

Sources & evidence

ORD record
ord-81f5a4b629f441eba6b90870d986d512
Source dataset
uspto-grants-2008_08
Patent number
US07417046B2

Reaction notes

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