Triisopropyl borate → 4-Bromo-3-isopropylanisole

Participants

Reaction Conditions

Reaction Steps

1-Bromo-2-isopropyl-4-methoxy-benzene was prepared in accordance with the procedures of Konishi et. al., Bull. Chem. Soc. Jpn., 1989, 62, 591-593. To a solution of 1-bromo-2-isopropyl-4-methoxy-benzene (4.5 g, 19.7 mmol) was added BuLi (1.6M in hexane, 14.8 mL, 23.7 mmol) at −78° C. The reaction mixture was stirred at −78° C. for 40 min, followed by addition of B(O-iPr)3 dropwise. The resulting mixture was stirred at −78° C. for 2 hours, then warmed to room temperature overnight. The reaction mixture was quenched with HCl (1N) and extracted with diethyl ether three times. The organic phase was washed with water, brine and dried (Na2SO4). Silica gel chromatography (10-30%EtOAc/heptane) provided 2.3 g of 4-methoxy-2-isopropyl-phenylboronic acid.

Provenance & Evidence