p-Bromochlorobenzene → HCID 58288432, compound

Participants

Reaction Steps

Under argon, 1 g (5.23 mmol) of 1-bromo-4-chlorobenzene in 2.5 ml of diethyl ether was added slowly to 254 mg (10.45 mmol) of magnesium turnings in 5 ml of diethyl ether. After the reaction had started, a further 1 g (5.23 mmol) of 1-bromo-4-chlorobenzene in 2.5 ml of diethyl ether was metered into the reaction mixture. The reaction mixture was stirred at room temperature for 30 min, 103 mg (1.05 mmol) of copper(I) chloride were added and the mixture was then cooled to −10° C. 2.09 g (10.45 mmol) of diethyl propan-2-ylidenemalonate were then slowly added dropwise. The reaction mixture was subsequently heated to reflux and stirred at this temperature for 3 h. 20 ml of ice-cold 1 M hydrochloric acid were then added very slowly. After separation of the phases, the aqueous phase was extracted three more times with diethyl ether. The combined organic phases were dried over magnesium sulphate and then concentrated to dryness. The crude product was purified by preparative HPLC (mobile phase methanol/water 70:30). This gave 800 mg of the title compound (25% of theory).

Provenance & Evidence