Boron trifluoride etherate → HCID 86697901, compound

Participants

Reaction Conditions

Reaction Steps

A −78° C. solution of 2-trimethylsilylthiazole (383 mg, 2.44 mmol) in tetrahydrofuran (3 mL) is treated drop wise with a solution of n-butyl lithium (1.52 mL, 2.44 mmol, 1.6 M hexanes) and the reaction is stirred at −78° C. for 10 minutes to give a thick orange slurry. The slurry is treated with boron trifluoride etherate (205 μL, 1.62 mmol) to give a red mixture and then a solution of benzyl (3aR)-3,3a,4,6-tetrahydropyrrolo[3,4-c]isoxazole-5-carboxylate (200 mg, 812 μmol) is added immediately in toluene (2 mL) to this mixture. The resultant mixture is stirred at −78° C. for 20 minutes under nitrogen. The reaction is quenched with saturated ammonium chloride and warmed to room temperature. Water and saturated sodium bicarbonate is added and the mixture is extracted with ethyl acetate (3×). The combined organic layers are dried over sodium sulfate and the solvent is removed under vacuum. The crude product is purified over silica gel eluting with 5% to 100% ethyl acetate in hexanes gradient, to give the title compound (245 mg, 75%). ES/MS (m/e): 404(M+H).

Provenance & Evidence