Twelve-membered cyclic cis- and trans-β-lactams 1b and 2b and the corresponding cyclic cis- and trans-β-amino acid enantiomers, 1a, 1c and 2a, 2c were prepared through the CAL-B-catalysed enantioselective ring cleavage of racemic cis-13-azabicyclo[10.2.0]tetradecan-14-one, (±)-1, and trans-13-azabicyclo[10.2.0]tetradecan-14-one, (±)-2. High enantioselectivities (E >200) were observed for the ring opening of both the cis- and trans-β-lactams when the Lipolase-catalysed reactions were performed with 0.5 equiv of H2O in i-Pr2O at 70 °C. The resolved β-lactams 1b and 2b (yield ≥47%) and β-amino acids 1a and 2a (yield ≥32%) could be easily separated.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry