1-Piperazinecarboxylic acid, ethyl ester → HCID 67813712, compound

HRID 923637Notes

Reaction equation

HRID 923637 reaction equation
[N:1]1([C:7]([O:9][CH2:10][CH3:11])=[O:8])[CH2:6][CH2:5][NH:4][CH2:3][CH2:2]1.[C:12](Cl)(=[O:23])[O:13][C:14]1[CH:19]=[CH:18][C:17]([N+:20]([O-:22])=[O:21])=[CH:16][CH:15]=1.CCN(CC)CC>C(Cl)Cl>[N:1]1([C:7]([O:9][CH2:10][CH3:11])=[O:8])[CH2:6][CH2:5][N:4]([C:12]([O:13][C:14]2[CH:15]=[CH:16][C:17]([N+:20]([O-:22])=[O:21])=[CH:18][CH:19]=2)=[O:23])[CH2:3][CH2:2]1

Participants

5

Reactant 3

HCID 84311-Piperazinecarboxylic acid, ethyl esterHCID 8471TriethylamineHCID 821294-Nitrophenyl chloroformate

Product 1

HCID 67813712HCID 67813712, compoundYield 45%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

A mixture of ethyl piperazine-1-carboxylate (300 mg, 1.90 mmol), 4-nitrophenyl carbonochloridate (460 mg, 2.28 mmol) and Et3N (576 mg, 5.69 mmol) in anhydrous CH2Cl2 (7 mL) was stirred at room temperature for 24 h, and then the reaction mixture turned to a yellow solution. Extraction with NaHCO3(aq.) until the organic layer turns to transparent solution. And then the organic layer was dried over MgSO4, filtered, concentrated, and purified by flash chromatography on a silica gel column with elution of EtOAc/hexane (1:1.5) to give 1-ethyl 4-(4-nitrophenyl) piperazine-1,4-dicarboxylate (172 mg, 45% yield). C14H17N3O6; pale yellow solid; mp 125-128° C.; IR vmax (neat) 3512, 3082, 2983, 2930, 2867, 1730, 1701, 1594, 1523, 1459, 1425, 1348, 1288, 1209, 1163, 1085, 1055, 996, 957 cm−1; 1H NMR (400 MHz, CDCl3) δ 8.23 (1H, d, J=8.8 Hz), 7.28 (1H, t, J=8.8 Hz), 4.17 (2H, q, J=6.8 Hz), 3.66 (2H, br s), 3.56 (6H, br s), 1.28 (3H, t, J=7.2 Hz); 13C NMR (100 MHz, CDCl3) δ 155.7, 155.1, 151.9, 144.7, 124.9 (2×), 122.1 (2×), 61.8, 44.5, 43.8, 43.4 (2×), 14.8.

Workup

  1. extractionExtraction with NaHCO3(aq.) until the organic layer
  2. dry with materialAnd then the organic layer was dried over MgSO4
  3. filtrationfiltered
  4. concentrationconcentrated
  5. custompurified by flash chromatography on a silica gel column with elution of EtOAc/hexane (1:1.5)

Sources & evidence

ORD record
ord-2de2f0885498433b87fbe49b3ff0e60f
Source dataset
uspto-grants-2016_03
Patent number
US09278982B2

Reaction notes

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