Lithium Hexamethyldisilazide → 1-(4-Chlorobenzo[b]thiophen-2-yl)-3-(3,5-dichlorophenyl)-4,4,4-trifluoro-3-hydroxybutan-1-one

Participants

Reaction Conditions

Reaction Steps

Add a solution of LiHMDS (1 M in THF, 4.3 ml, 4.31 mmol) to a mixture of 1-(4-chlorobenzo[b]thiophen-2-yl)ethanone (0.6 g, 2.87 mmol) in dry THF (10 mL) at −78° C. under N2. After stirring 1.5 hour at −78° C., add 1-(3,5-dichlorophenyl)-2,2,2-trifluoroethanone (836 mg, 3.44 mmol) to the reaction mixture and stir the resultant mixture for additional 2 hours. Quench the reaction with saturated NH4Cl solution and extract the aqueous mixture with EtOAc (10 mL×3). The combined organic layers are washed with brine, dried over anhydrous Na2SO4 and concentrated under vacuum afford crude 1-(4-chlorobenzo[b]thiophen-2-yl)-3-(3,5-dichlorophenyl)-4,4,4-trifluoro-3-hydroxybutan-1-one as brown solid (1.1 g, 84.6%). 1H NMR (400 MHz, CDCl3) δ 8.10-8.07 (s, 1H), 7.75 (d, J=5.2, 1H), 7.47-7.36 (m, 2H), 2.72-2.68 (s, 3H).

Provenance & Evidence