Triisopropyl borate → 3-Benzyloxy-phenylboronic acid

Participants

Reaction Steps

A solution of 3-benzyloxy-bromobenzene 10 g (38 mmol) in 150 mL of anhydrous THF was cooled to -70° C. under a nitrogen atmosphere. 28.5 mL of n-butyl lithium (1.6 M in hexanes) was added dropwise to the solution. The reaction mixture was stirred for 30 minutes, then tri-isopropyl borate 10.6 mL (45.6 mmol) was added. The reaction mixture was allowed to warm to ambient temperature over a two hour period. The reaction was quenched by the addition of 200 mL of 1 N HCl and the reaction mixture was stirred for an additional hour. The slurry was extracted twice with EtOAc and the organic layer separated and combined. The EtOAc solution was washed twice with brine, dried with Na2SO4, and evaporated to a yellow oil. The product was crystallized from ether-hexane. This yielded 4.85 g of the title compound as white solid.

Provenance & Evidence