4,4'-Dibromobiphenyl → 4'-Bromo-4-biphenylboronic Acid (contains varying amounts of Anhydride)

Participants

Reaction Conditions

Reaction Steps

10.0 g (0.032 mol) of 4,4′-dibromobiphenyl was put in a 500 mL three neck flask, and nitrogen was substituted for air in the flask, and then 200 mL of tetrahydrofuran was added and stirred at −80° C. 20 mL (0.032 mol) of n-butyllithium (1.60 M hexane solution) was dropped into a reaction solution, and stirred for 1 hour at −80° C., and 40 mL (0.060 mol) of trimethyl borate was added and stirred for 1 hour while returning to room temperature. After 200 mL (1.0 mol/L) of hydrochloric acid water was added to the reaction solution, and stirred for about 12 hours, an organic layer was washed with a saturated sodium hydrogen carbonate solution and saturated saline, and then dried with magnesium sulfate. After the reaction solution was naturally filtered, a solid which was obtained by concentrating a filtrate, was recrystallized with a mixture of ethyl acetate and hexane. 3.7 g of 4-(4-bromophenyl)phenylboronic acid that was a target substance and was a white solid was obtained in a yield of 41% (Synthesis Scheme (e-1)).

Provenance & Evidence