Bismuth(III) Triflate-Based Catalytic Direct Opening of Oleanolic Hydroxy-gamma-lactones to Afford 12-Oxo-28-carboxylic Acids

作者：Salvador Jorge A R^*; Moreira Vania M; Pinto Rui M A; Leal Ana S; Le Roux Christophe

来源：Advanced Synthesis & Catalysis, 2011, 353(14-15): 2637-2642.

DOI：10.1002/adsc.201100155

• bismuth(III) triflate
• hydroxylactones
• oleanolic compounds
• 12-oxo-28-carboxylic acids
• pentacyclic triterpenoids

The bismuth(III) triflate-based catalytic direct opening of oleanolic hydroxy-gamma-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 Bronsted acid species from bismuth-(III) triflate is most likely involved in the reaction mechanism. Full structural elucidation of the products obtained has been performed by 1D and 2D NMR techniques.

• 出版日期2011-10