Toluene → HCID 4867618, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 4-Benzyl-5-[4-(-4-benzyl-2-oxo-oxazolidin-3-yl)-4-oxo-but-2-enyl]-2,2-dimethyl-oxazolidine-3-carboxylic acid tert-butyl ester (13.35 g, 25 mmol) in dichloromethane (500 ml) was stirred at −78° C. under nitrogen during the addition of 2-trimethylsiloxy-1,3-butadiene (26 ml, 150 mmol) and 1.8 M diethylaluminium chloride solution in toluene (70 ml, 125 mmol). The resulting pale yellow solution was stirred at −78° C. for 48 hours then slowly added to vigorously stirred, ice-cold 1 M hydrogen chloride aqueous solution. After 1 hour the two layers were separated and the aqueous phase was extracted twice with ethyl acetate. The combined organic layers were washed with a saturated aqueous sodium hydrogen carbonate solution and brine, dried (anhydrous magnesium sulfate) and concentrated in vacuo to give, after purification by flash chromatography on silica gel (ethyl acetate/hexane 1/9 to 4/6), 4-Benzyl-5-[2-(4-benzyl-2-oxo-oxazolidine-3-carbonyl)-5-oxo-cyclohexylmethyl]-2,2-dimethyl-oxazolidine-3-carboxylic acid tert-butyl ester (8.7 g) as a white foam.

Provenance & Evidence