Phosphorus pentachloride → Methyl 3-chloro-2,2-dimethylbut-3-enoate

Participants

Reaction Steps

To a suspension of PCl5 (161 g, 0.772 mol) in dichloromethane (600 mL) was added dropwise methyl 2,2-dimethyl-3-oxobutanoate (52 g, 0.361 mol, crude from last step) at 0° C., followed by the addition of approximately 20 drops of dry DMF. The mixture was heated at reflux overnight. After cooling, the reaction mixture was slowly poured into ice water. The organic layer was separated and the aqueous phase was extracted with dichloromethane (300 mL×3). The combined organic layers were washed with saturated aqueous NaHCO3 solution and dried over anhydrous Na2SO4. The solvent was evaporated to give the product, methyl 3-chloro-2,2-dimethylbut-3-enoate which was used without further purification (47 g, 82%).

Provenance & Evidence