Dimethyl Sulfoxide → 2-Chloro-1,3-dicyclopropylpropane-1,3-dione

Participants

Reaction Steps

Trimethylsilyl chloride (16.6 ml, 130 mmol) was added to a solution of tert-butylammonium bromide (0.70 g, 2.17 mmol) in acetonitrile (50 ml) under nitrogen at 0° C. 1,3-Dicyclopropyl-propane-1,3-dione (ref: WO98155438) (6.62 g, 43.5 mmol) in acetonitrile (15 ml) was then added followed by dimethylsulfoxide (9.25 ml, 130 mmol) dropwise, and the reaction was allowed to warm to room temperature over 4 hours. The mixture was diluted with water (75 ml), extracted with diethylether (3×35 ml) and the combined organic extracts dried over magnesium sulphate and concentrated under reduced pressure. The residue was purified by flash chromatography on silica gel eluting with pentane:diethylether (95:5, by volume) to provide the title compound (3.76 g) as an oil, which was an 80:20 mixture of enol:keto forms.

Provenance & Evidence