Boron trifluoride etherate → 4-Tert-butoxy-cyclopent-2-enone

HRID 2547

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HRID 2547 반응식
[OH:1][CH:2]1[CH2:6][C:5](=[O:7])[CH:4]=[CH:3]1.ClC(Cl)(Cl)C(=N)O[C:12]([CH3:15])([CH3:14])[CH3:13].B(F)(F)F.CCOCC.C(=O)(O)[O-].[Na+]>C(Cl)Cl>[C:12]([O:7][CH:5]1[CH2:6][C:2](=[O:1])[CH:3]=[CH:4]1)([CH3:15])([CH3:14])[CH3:13]

참가 물질

6

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온도
6.5 °C

실험 절차

A solution of 4-hydroxy-2-cyclopentenone (1.15 g, 11.7 mmol) in methylene chloride is cooled to 3° C. and treated sequentially with tert-butyl trichloroacetimidate (4.2 mL, 23.7 mmol) and boron trifluoride diethyl etherate (0.15 mL). The reaction mixture is stirred at 3-10° C. for 2 hours and then allowed to warm to room temperature and stirred for 22 hours. The reaction mixture is then treated with sodium bicarbonate (250 mg) and filtered. The filtrate is concentrated under vacuum and the residue is purified by chromatography (silica gel, 39 g, 20% ethyl acetate/hexane, 600 mL) to provide the title compound (355 mg, 40%) as a yellow oil; 1H NMR (CDCl3)δ7.44 (dd, 1H, J=18 Hz), 6.2 (d, 1H, J=5.4 Hz), 4.8 (m, 1H), 2.68 (dd, 1H, J=5.8, 18 Hz), 2.25 (d, 1H, J=18 Hz), 1.27 (s, 9H); IR (neat) νmax 2976, 2936, 1721, 1368, 1352, 1188, 1103, 1161 cm-1 ; MS (CI) m/e (% relative intensity) 155 (M+H+, 22), 99 (100).

후처리

  1. temperatureto warm to room temperature
  2. stirringstirred for 22 hours
  3. filtrationfiltered
  4. concentrationThe filtrate is concentrated under vacuum
  5. customthe residue is purified by chromatography (silica gel, 39 g, 20% ethyl acetate/hexane, 600 mL)

출처 및 근거

ORD 기록
ord-46441d6502ac4bf9a6e8aa14f7c747f1
출처 데이터셋
uspto-grants-1998_03
특허 번호
US05728899

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