Excess water was removed from a 2L round-bottomed flask by drying it under a flame. Then, Potassium t-butoxide (34.00g, 303.0mmol, 1.10 equiv), pentane or hexanes (400 mL), and 2,3-dimethyl-2-butene (60.00 mL, 42.48 g, 543.8 mmol, 1.98 equiv) were added. While stirring, the reaction mixture was cooled to 0˚C in an ice-water bath and then wrapped in aluminum foil. Within an hour, bromoform (24.00mL, 69.36g, 274.4 mmol, 1.00 equiv) was distilled ove r CaCl2 and added to the reaction three times. Afterwards, the reaction flask was removed from the ice water bath and warmed to room temperature for two hours. Once the volatile, excess components of the reaction mixture were evaporated off in vacuo, N,N-dimethylaniline (150 mL, 143.4 g, 1183.3 mmol, 4.31 equiv) was added. The reaction mixture was then heated under reflux in a 150˚C oil bath for 20 minutes. Soon after, the mixture was cooled to room temperature and then Et2O (800 mL) and aqueous hydrochloric acid (3 N; 400 mL) were added. The organic layer was obtained using liquid-liquid extraction and washed three times with hydrochloric acid (3 N; 2 x 400 mL), followed by water (400 mL) and lastly, brine (400 mL). A yellow liquid was produced when the organic layer was dried over anhydrous MgSO4, filtered, and concentrated in vacuo. Using an alumina plug, the resulting liquid was further purified into a less yellow, non-viscous liquid.
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