Benzyl 3-oxopiperazine-1-carboxylate → 5-Ethoxy-3,6-dihydro-2H-pyrazine-1-carboxylic acid benzyl ester

HRID 394537

반응식

HRID 394537 반응식
[CH2:1]([O:8][C:9]([N:11]1[CH2:16][CH2:15][NH:14][C:13](=[O:17])[CH2:12]1)=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.F[B-](F)(F)F.[CH2:23]([O+](CC)CC)[CH3:24]>ClCCl>[CH2:1]([O:8][C:9]([N:11]1[CH2:12][C:13]([O:17][CH2:23][CH3:24])=[N:14][CH2:15][CH2:16]1)=[O:10])[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

참가 물질

4

반응물 2

HCID 736777Benzyl 3-oxopiperazine-1-carboxylateHCID 2723982Triethyloxonium tetrafluoroborate

생성물 1

HCID 542316815-Ethoxy-3,6-dihydro-2H-pyrazine-1-carboxylic acid benzyl ester수율 95%

시약·촉매·용매 1

HCID 6344Dichloromethane용매

실험 절차

To a solution of 3-oxo-piperazine-1-carboxylic acid benzyl ester (2.0 g, 8.54 mmol, Maybridge) in dichloromethane (18 mL) at room temperature was added triethyloxonium tetrafluoroborate (4.1 g, 21.3 mmol). This mixture was allowed to stir for about 3 days then quenched by the addition of ice chips followed by saturated aqueous sodium bicarbonate until a neutral pH was obtained. The organic layer was separated and the aqueous layer was extracted with chloroform (3×). The combined organic extracts were washed with brine (1×), dried over sodium sulfate, and concentrated to give 2.11 g (95%) of the title compound of Example 259, Step A as a slightly yellow oil that was sufficiently pure to carry on to the next step. 1H NMR (CDCl3, 300 MHz) δ 7.43-6.97 (c, 5H), 5.17 (s, 2H), 4.10 (q, 2H), 3.98 (s, 2H), 3.60-3.40 (c, 4H), 1.27 (t, 3H); MS (APCI) 263 (MH+).

후처리

  1. customthen quenched by the addition of ice chips
  2. customwas obtained
  3. customThe organic layer was separated
  4. extractionthe aqueous layer was extracted with chloroform (3×)
  5. washThe combined organic extracts were washed with brine (1×)
  6. dry with materialdried over sodium sulfate
  7. concentrationconcentrated

출처 및 근거

ORD 기록
ord-d884e7109bdd44abae4c2de4bab70bf8
출처 데이터셋
uspto-grants-2003_08
특허 번호
US06602875B2

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