반응 #2642

ord-fcb0d5dcdda04901928d4fd9c09849c7

반응 방정식

[Na+].[OH-]
sodium hydroxide
[Al+3].[H-].[H-].[H-].[H-].[Li+]
lithium aluminum hydride
[I-].[Li+]
lithium iodide
O=C1C=CC(OC2CCCCO2)C1
4-(tetrahydro-pyran-2-yloxy)-cyclopent-2-enone
O[C@@H]1C=C[C@H](OC2CCCCO2)C1
title compound
수율 73.5%
O[C@@H]1C=C[C@H](OC2CCCCO2)C1
cis-4-(tetrahydro-pyran-2-yloxy)-cyclopent-2-enol
수율 73.5%

반응 조건

상세 조건
See reaction.notes.procedure_details.

후처리

  1. 1
    여과The slurry is filtered
  2. 2
    기타the resulting phases separated
  3. 3
    추출The aqueous phase is extracted with ethyl acetate (2×10 mL)
  4. 4
    건조dried over magnesium sulfate
  5. 5
    여과filtered
  6. 6
    농축concentrated under vacuum
  7. 7
    기타The crude oil is then purified by chromatography (silica gel, 30 g, 50% ethyl acetate/hexane, 400 mL)

실험 절차

A slurry of lithium aluminum hydride (222 mg, 5.8 mmol), lithium iodide (3.2 g, 24 mmol), tert-butyl methyl ether (6 mL) and toluene (16 mL) is cooled to -15° C. A solution of 4-(tetrahydro-pyran-2-yloxy)-cyclopent-2-enone (2.179 g, 11.97 mmol, prepared in example 5) in tert-butyl methyl ether (2 mL) and toluene (2 mL) is added dropwise over 40 minutes. The reaction mixture is allowed to stir for 30 minutes. Then sodium hydroxide (1N, 5 mL) is added slowly to the reaction mixture. The slurry is filtered and the resulting phases separated. The aqueous phase is extracted with ethyl acetate (2×10 mL). The organic extracts are combined with the organic phase, dried over magnesium sulfate, filtered and concentrated under vacuum. The crude oil is then purified by chromatography (silica gel, 30 g, 50% ethyl acetate/hexane, 400 mL) to provide the title compound (1.62 g, 73%), cis/trans/1-2+1-4 addition, 88/8/4; 1H NMR (CDCl3) δ6.1 (m, 1H), 4.7 (m, 1H), 4.6 (m, 2H), 3.9 (m, 1H), 3.5 (m, 1H), 2.7 (m, 1H), 1.4-2.0 (m, 8H); 13C NMR (CDCl3) δ 137.2,137.1, 134.8, 133.6, 98.3, 97.8, 79.7, 79.5, 74.7, 74.5, 62.6, 62.5, 42.0, 41.1, 31.1, 30.9, 25.4, 19.6, 19.5; IR (neat) νmax 2944, 2870, 2855, 1723, 1348, 1202, 1182, 1152, 1128, 1078, 1032 cm-1 ; MS (CI) m/e (% relative intensity) 183 (M+H+, 7), 167 (M+H+ -H2O, 40), 85(100).

출처

DOI: 10.6084/m9.figshare.5104873.v1특허: US05728899uspto-grants-1998_03