Carbon tetrabromide → Di-tert-butyl phosphorobromidate

Participants

Reaction Steps

A 500 mL 3-neck flask equipped with dropping funnel and thermometer was charged with carbon tetrabromide (16.58 g, 50 mmol), benzyltriethylammonium chloride (1.14 g, 5.0 mmol) and dichloromethane (50 mL). A 20% w/w NaOH solution (50 mL) was added with vigorous stirring, followed by dropwise addition of a solution of di-tert-butylphosphite (20 g, 100 mmol) in dichloromethane (20 mL), the rate of addition was controlled to keep the temperature of reaction mixture not to exceed to 25° C. After addition of phosphite, the mixture was further stirred at room temperature for 3 h, diluted with dichloromethane (20 mL) and separated. The organic phase was washed with saturated sodium bisulfite, water, brine, dried (Na2SO4), filtered and concentrated at RT. After removing the solvent, the residue was further pumped in vacuo for 1 h to give di-tert-butyl phosphorobromidate as a colorless oil (23.5 g, 86%).

Provenance & Evidence