Elsevier, Tetrahedron: Asymmetry, 16(27), p. 729-731
DOI: 10.1016/j.tetasy.2016.06.019
Full text: Unavailable
A very efficient enzymatic two-step cascade reaction was devised (E > 200) for the resolution of activated gamma-lactams (+/-)-1 and (+/-)-2. The N-hydroxymethyl group worked as a traceless activating group, when the reactions were performed with H2O (0.5 equiv) in the presence of benzylamine (1 equiv) in i-Pr2O at 60 degrees C. The ring-opened enantiomerically pure gamma-amino acids (1S,4R)-6 (ee = 99%, intermediate of abacavir) and (1S,3R)-8 (ee = 99%) and unreacted lactams (1S,4R)-1 and (1R,4S)-2 (ee >= 96%) were obtained in good yields (>= 43%). Treatment of (1S,4R)-1 and (1R,4S)-2 with 18% HCl or NH4OH resulted in (1R,4S)-6 center dot HCl and (1S,3R)-8 center dot HCI or (15,4R)-3 and (1R,4S)-4 quantitatively, with ee >= 96%. (C) 2016 Elsevier Ltd. All rights reserved.