Boron trifluoride etherate → HCID 117966726, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of (R)-2-benzyl 1-tert-butyl 4,4-dimethyl-5-oxopyrrolidine-1,2-dicarboxylate (D39) (210 mg, 0.6 mmol) in THF (10 ml) cooled at −78° C., LiEt3BH 1M sol in THF (0.6 ml) was added and the mixture stirred 2 hrs at −78° C. The reaction was warmed to 0° C. and quenched with slow addition of NaHCO3 sat sol (4 ml) and 1 drop of H2O2. Stirring was continued for 20 min then THF was removed under reduced pressure and the remaining residue was taken up in water (5 ml) and extracted with DCM (3×10 ml). The organic phases were collected, dried over Na2SO4 and evaporated in vacuo. The obtained residue was dissolved in DCM (10 ml) and cooled at −78° C. under N2. Et3SiH (0.09 ml, 0.6 mmol) was added followed by addition of BF3.OEt2 (0.1 ml, 0.63 mmol) and the reaction stirred 30 min, prior further addition of Et3SiH (0.09 ml, 0.6 mmol) and BF3.OEt2 (0.1 ml, 0.63 mmol). The final reaction mixture was stirred at −78° C. for 3 hrs then quenched by the slow addition of saturated NaHCO3 and water. The reaction mixture was extracted with DCM (3×10 ml), the organic layers washed with NaCl sat sol, dried over Na2SO4 and evaporated to afford the title compound (D40) (168 mg).

Provenance & Evidence