Boron trifluoride etherate → (-)-Benzyl (R)-glycidyl ether

Participants

Reaction Conditions

Reaction Steps

A solution of n-butyllithium (2.5M in hexane, 72 mL, 180 mmol) was added dropwise to a solution of diethyl methylphosphonate (27.4 g, 180 mmol) in 200 mL dry tetrahydrofuran (THF) at -78° C. After 30 minutes of stirring at -78° C., the resulting white suspension was added in a slow stream through a cannula to a stirred solution of BF3.Et2O (22.13 mL, 180 mmol) in THF (400 mL) at -78° C. After 10 minutes, neat (R)-(-)-2-(benzyloxymethyl)oxirane 1-1 (10 g, 61 mmol, obtained from the Aldrich Chemical Co.) was added quickly to this suspension. The reaction mixture was stirred for 30 minutes at -78° C., quenched by adding saturated aqueous NaHCO3 (100 mL) and allowed to warm to room temperature. The reaction was diluted with 450 mL of ether and washed with 2×200 mL of saturated sodium bicarbonate solution and 100 mL of brine. The ether layers were dried (MgSO4) and evaporated. The residue was chromatographed on silica gel, eluting with 5% methanol/95% dichloromethane to give the product 1-2 as a pale yellow oil (18.0 g, 94%).

Provenance & Evidence