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 236g 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 220.5g 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 100.5g of p-diphenylphosphinobromobenzene, mp 78°-80° C.

Provenance & Evidence