反应详情

To a suspension of sodium hydride (729 mg 60% in mineral oil) in N,N-dimethylformamide containing one drop of pentane is added (4-benzyloxybenzyl)triphenylphosphonium chloride (7.52 g). The mixture is stirred for 40 min, then 1,4-dioxaspiro[4.5]decan-8-one (2.37 g) is added. The mixture is stirred for one hour at room temperature, the suspension turning from red to green. The mixture is poured into ice (250 g) and extracted with ethyl acetate (4 times 100 mL). The organic extracts are pooled, washed with saturated aqueous solution of sodium chloride (3 times 50 mL), dried over magnesium sulfate, concentrated under reduced pressure and purified by column chromatography over silica gel using a gradient heptane/ethyl acetate from 90/10 to 60/40 to give 2.43 g of 8-(4-benzyloxybenzylidene)-1,4-dioxaspiro[4.5]decane as a colorless oil.

1. stirringThe mixture is stirred for one hour at room temperature
2. extractionextracted with ethyl acetate (4 times 100 mL)
3. washwashed with saturated aqueous solution of sodium chloride (3 times 50 mL)
4. dry with materialdried over magnesium sulfate
5. concentrationconcentrated under reduced pressure
6. custompurified by column chromatography over silica gel using a gradient heptane/ethyl acetate from 90/10 to 60/40