Hydrochloric Acid → 2'-Benzyloxy-biphenyl-2-boronic acid

Participants

Reaction Steps

A solution of 2′-benzyloxy-2-bromobiphenyl (2.41 g, 7.09 mmol) in tetrahydrofuran (50 ml) was stirred under nitrogen and cooled to −100° C. (diethyl ether/liquid nitrogen). 1.6M nButyllithium in hexanes (4.87 ml, 7.80 mmol) was added over 15 mins. at −100° C. and the mixture warmed to −78° C. (acetone/Drikold) and stirred for 1 h. Triisopropyl borate (4.00 g (5.02 ml, 21.30 mmol) was added at −78° C. and the reaction allowed to warm to room temperature with stirring over 1.5 h. 1M Hydrochloric acid (50 ml) was added and the mixture stirred vigorously for 1 h. The organic layer was separated and the aqueous layer extracted with diethyl ether (50 ml). The combined organic phase were washed with water, dried (MgSO4) and the solvent removed in vacuo. The yellow oil was flash chromatographed (silica gel, 10-20% EtOAc-isohexane) to give the title compound as a clear oil (1.74 g, 80%). LC/MS RT=3.28 min [(2M−H2O)H−]=589.3

Provenance & Evidence