反应详情

Cis-Methyl 2-(cyclohexyloxymethyl)-4-(3-oxo-2,3-dihydroisoxazol-5-yl)piperidine-1-carboxylate (423 mg, 1.25 mmol) was subjected to chiral preparative HPLC (Column: Chiralpak IC (250×20), 5 μm particle size, mobile phase: Heptane/EtOH 70/30, flow rate 18 mL/min) to yield (2R,4S)-methyl 2-(cyclohexyloxymethyl)-4-(3-oxo-2,3-dihydroisoxazol-5-yl)piperidine-1-carboxylate (190 mg, 45%), Chiral purity 98.3% ee, Optical rotation [α]D20=+55.9 (acetonitrile, c=1) and (2S,4R)-methyl 2-(cyclohexyloxymethyl)-4-(3-oxo-2,3-dihydroisoxazol-5-yl)piperidine-1-carboxylate (194 mg, 46%), Chiral purity 98.6% ee, Optical rotation [α]D20=−55.4 (acetonitrile, c=1)