The bismuth(III) triflate-based catalytic direct opening of oleanolic hydroxy-g-lactones affords the corresponding 12-oxo-28-carboxylic acid derivatives, in both acetonitrile and dichloromethane, at reflux, in high yields. Participation of an in situ generated Brønsted acid species from bismuth (III) triflate is most likely involved in the reactionmechanism. Full structural elucidation of the products obtained has been performed by 1D and 2D NMR techniques.
- bismuth(III) triflate
- oleanolic compounds
- pentacyclic triterpenoids
Salvador, J. A. R., Moreira, V. M., Pinto, R. M. A., Leal, A. S., & Le Roux, C. (2011). Bismuth(III) triflate-based catalytic direct opening of oleanolic hydroxy-gamma-lactones to afford 12-oxo-28-carboxylic acids. Advanced Synthesis and Catalysis, 353(14-15), 2637-2642. https://doi.org/10.1002/adsc.201100155