1,4-Dibromobenzene → (4-Bromophenyl)diphenylphosphine

Participants

Reaction Conditions

Reaction Steps

To 1.0 mole of n-butyllithium in hexane at -78° C. under an inert atmosphere is added dropwise and with efficient stirring 236 g of p-dibromobenzene in dry tetrahydrofuran (total volume 500 ml). The resulting solution is stirred at -78° C. for 1 hour, then treated dropwise at this temperature with 220.5 g of chlorodiphenylphosphine. When this addition is complete, the mixture is allowed to warm to room temperature, then solvent is removed under vacuum. The residue is triturated with two 400-ml portions of methanol, then distilled through a Vigreux column. The cut with bp 165°-170° C. (0.15 mm) is recrystallized from ethanol to give 100.5 g of p-diphenylphosphinobromobenzene, mp 78°-80° C.

Provenance & Evidence