Potassium Hydroxide → [5'-Isopropyl-2'-methoxy-4-(trifluoromethyl)biphenyl-2-yl]methanol

Participants

Reaction Conditions

Reaction Steps

To a solution of 1.08 g of 5′-isopropyl-2′-methoxy-4-(trifluoromethyl)biphenyl-2-carbonitrile (EXAMPLE 3) in 25 mL of n-PrOH, was added 0.97 g of KOH. The mixture was heated to reflux and stirred at this temperature for 36 h, then cooled and concentrated to a clear oil. This oil was partitioned between 15 mL of water and 10 mL of Et2O. The aqueous phase was extracted with 10 mL of Et2O. The combined organics were washed with brine (15 mL), dried over Na2SO4, and concentrated. The residue was purified by flash chromatography on a Biotage Horizon 40S column, eluting with 1 CV of 95% hexanes-5% of a mixture of 5% formic acid in acetone, followed by a linear gradient of the acetone mixture in hexanes from 5 to 100% over 10 CV. The resulting white solid was dissolved in 10 mL of 9:1 benzene-MeOH and excess TMSCH2N2 was added. The mixture was stirred for 10 min at room temperature, then quenched with trifluoroacetic acid and concentrated. The residue was dissolved in 15 mL of Et2O and cooled to 0° C. A 1-M solution of LiAlH4 in Et2O (5.4 mL) was added dropwise via addition funnel. The cooling bath was removed once the addition was complete, and the mixture was stirred 2 h at room temperature, then recooled to 0° C. and quenched by dropwise addition of 0.2 mL of water, 0.2 mL of 15% aqueous NaOH, and 0.5 mL of water. The cooling bath was removed once the addition was complete, and the mixture was stirred 30 min at room temperature, filtered (washing the solids liberally with Et2O), and concentrated. Flash chromatography on a Biotage Horizon, 40S column, eluting with 1 CV of 4% EtOAc in hexanes, followed by a linear gradient of EtOAc in hexanes from 4 to 100% over 10 CV provided the title compound. Mass spectrum (ESI) 307.2 (M−17). 1H NMR (500 MHz, CDCl3): δ 7.85 (s, 1H), 7.60 (d, J=8 Hz, 1H), 7.33 (d, J=8 Hz, 1H), 7.25 (dd, J=2 Hz, 9 Hz, 1H), 6.99 (d, J=2.5 Hz, 1H), 6.93 (d, J=8.5 Hz, 1H), 4.49 (m, 2H), 3.74 (s, 3H), 2.90 (septet, J=7 Hz, 1H), 1.25 (d, J=7 Hz, 6H).

Provenance & Evidence