反应详情

50 g (0.32 mol) of methyl trans-2-aminocyclohexanecarboxylate were dissolved in 200 ml of MTBE and, after addition of 0.16 mol of isopropyl methoxyacetate and 0.5 g of Novozym 435 (Novo Nordisk), shaken at room temperature for 8 h. The enzyme was filtered off and then the solvent was removed and the residue was distilled under reduced pressure. 23.5 g of methyl (1S,2S)-2-aminocyclohexanecarboxylate and 35.2 g of methyl (1R,2R)-2-(2-methoxyacetylamino) cyclohexanecarboxylate were obtained, each with an ee of 99.8%. The ee of the amine was determined after N-acylation with acetic anhydride by gas chromatography on a B-PH GC column (supplied by Astec, N.J., USA), while the N-2-methoxyacetamide was put on this column without derivatization.

1. filtrationThe enzyme was filtered off
2. customthe solvent was removed
3. distillationthe residue was distilled under reduced pressure