C([Li])CCC.[CH3:6][S:7]([C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1)(=[O:9])=[O:8].[O:16]([CH2:23][C:24](OCC)=[O:25])[C:17]1[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1>O1CCCC1>[C:10]1([S:7]([CH2:6][C:24](=[O:25])[CH2:23][O:16][C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)(=[O:9])=[O:8])[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1n-Butyllithium (8.5 ml, 1.6M in hexane) was added at -72° C. to a solution of methylphenyl sulfone (2.14 g, 13.7 mmol) in 80 ml of tetrahydrofuran. The reaction mixture was then allowed to warm slowly to -20° C. and maintained at this temperature for 25 minutes. It was then recooled to -72° C. and ethyl phenoxyacetate (1.48 g, 8.22 mmol) was added dropwise. The cooling bath was removed, the mixture was stirred at 20° C. for 14 hrs. and then poured into 100 ml of saturated NH4Cl and extracted with diethyl ether. The combined organic extracts were washed with brine, dried over anhydrous magnesium sulfate and the solvent removed under reduced pressure. The crude residue was purified by column chromatography (silica gel, methylene chloride) giving 1-phenylsulfonyl-2-oxo-3-phenoxypropane, the compound of formula (2a), 800 mg.
Wird geladen…
