Boron trifluoride etherate → HCID 21099443, compound

Participants

Reaction Conditions

Reaction Steps

Lithium chloride (0.57 g, 13.5 mmol, dried at 140° C. under vacuum) and copper(I) cyanide (0.605 g, 6.8 mmol) were dissolved in tetrahydrofuran (5 mL) and cooled to −40° C. under nitrogen. 4-Fluorobenzylzinc chloride (0.5M in tetrahydrofuran, 15 mL) was added dropwise and the solution cooled to −20° C. for 5 minutes then to −78° C. Boron trifluoride diethyl etherate (1.7 mL, 13.5 mmol) and 4-(phenylsulfonyl)benzaldehyde (Example 113 Step 1, 300 mg, 1.2 mmol) in tetrahydrofuran (5 mL) were added and the reaction stirred at −78° C. for 30 minutes then warmed to 25° C. and quenched with saturated ammonium chloride solution. Ethyl acetate was added and the mixture stirred for 10 minutes then the layers separated. The organic layer was washed with brine, dried over MgSO4 and evaporated. The residue was purified by flash column chromatography on silica, eluting with 40% ethyl acetate/isohexane, to give the title compound as a white solid (0.386 g, 90%). δH (360 MHz, CDCl3): 7.94–7.88 (4H, m), 7.58–7.43 (5H, m), 7.10–7.02 (2H, m), 6.99–6.93 (2H, m), 4.92–4.88 (1H, m), 2.99–2.85 (2H, m), 2.01 (1H, d, J=3.2 Hz).

Provenance & Evidence