Triisopropyl borate → 4-Chloro-3-(5-(trifluoromethyl)pyridin-2-yloxy)phenylboronic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-(5-bromo-2-chlorophenoxy)-5-(trifluoromethyl)pyridine (2.6 g, 7.3 mmol) and triisopropylborate (2.0 mL, 8.76 mmol) in toluene (15 mL) and THF (7 mL) under a N2 atmosphere was added n-BuLi (6.8 mL, 10.95 mmol) while maintaining the reaction at −70° C. The reaction was stirred for 1 h at −40° C. Gradually the temperature was increased to −20° C. and then 0° C. The reaction was quenched with 2N HCl and allowed to warm to RT. The reaction mixture was concentrated and extracted with EtOAc. The organic extract was dried over Na2SO4 and concentrated under reduced pressure to give the title compound (2.8 g). 1H NMR (500 MHz, DMSO-d6): δ 8.56 (s, 1H), 8.29 (m, 3H), 7.94 (s, 1H), 7.81 (d, J=7.9 Hz, 1H), 7.36 (d, J=8.05 Hz, 2H); m/z (316.4, M− H−).

Provenance & Evidence