16152-51-5

99-88-7

73183-34-3

16152-51-5

The general procedure for the synthesis of 4-isopropylphenylboronic acid from 4-isopropylaniline and pinacol ester of bis(pinacolato)diboron was as follows: to a stirred solution of 4-isopropylaniline (1 g, 7.4 mmol) in acetonitrile (30 mL) was added drop-wise isopentyl nitrite (1.3 mL, 11.1 mmol) and bis(pinacolato)diboron (2.24 g, 8.8 mmol) at 0 °C. The reaction mixture was warmed to 80 °C and stirred continuously for 2 hours. Upon completion of the reaction, the solvent was removed by distillation under reduced pressure and the resulting crude product was purified by silica gel column chromatography (combiflash) using 4% ethyl acetate/hexane as eluent to give 4-isopropylphenylboronic acid as a brown solid (1.2 g, 99.8% yield). The product was characterized by 1H NMR (400 MHz, CDCl3): δ 7.74 (d, J = 8.0 Hz, 2H), 7.24 (d, J = 8.4 Hz, 2H), 2.93-2.87 (m, 1H), 1.33 (s, 12H), 1.25 (d, J = 7.2 Hz, 6H).