P([O:8][CH2:9][CH3:10])(OCC)OCC.C[O:12][CH2:13][CH2:14]CC.[CH3:17][C:18](C)([O-:20])C.[K+].[CH2:23]([O:30][C:31]1[CH:38]=[CH:37][C:34]([CH:35]=O)=[CH:33][CH:32]=1)[C:24]1[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=1>O.C(O)(C)(C)C>[CH2:18]([O:20][C:9](=[O:8])[C:10]([O:12][CH2:13][CH3:14])=[CH:35][C:34]1[CH:37]=[CH:38][C:31]([O:30][CH2:23][C:24]2[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=2)=[CH:32][CH:33]=1)[CH3:17]P(OEt)3 was added dropwise to a mixture of tent-butyl methyl ether 55 mL) and potassium tert-butoxide (4.65 g, 41.4 mmol) under a nitrogen atmosphere at 20-30° C. 4-Benzyloxybenzaldehyde (4.61 g, 21.7 mmol) was added in portions to this mixture at 5° C. followed by the addition of tert-butyl alcohol (6.70 g). The reaction mixture was allowed to reach 15° C. and stirred at this temperature for approximately 30 min, after which the reaction was completed (as judged by TLC). Water (30 mL) was added at 5-10° C., and the phases were allowed to separate. The organic phase was concentrated in vacuo, and ethanol (30 mL) was added to the stirred solution. After crystallization had occurred, water (18 mL) was added to the suspension. The light-yellow title compound was filtered off, washed with ethanol/water (1:1 v/v), and dried in vacuo to yield 6.52 g (92% yield).
Wird geladen…