An Enantioselective Route to α-Methyl Carboxylic Acids via Metal and Enzyme Catalysis
摘要:
Dynamic kinetic resolution of allylic alcohols to allylic acetates followed by copper-catalyzed allylic substitution gave alkenes in high yields and high optical purity. Subsequent oxidative C-C double bond cleavage afforded pharmaceutically important alpha-methyl substituted carboxylic acids in high ee.
An Enantioselective Route to α-Methyl Carboxylic Acids via Metal and Enzyme Catalysis
摘要:
Dynamic kinetic resolution of allylic alcohols to allylic acetates followed by copper-catalyzed allylic substitution gave alkenes in high yields and high optical purity. Subsequent oxidative C-C double bond cleavage afforded pharmaceutically important alpha-methyl substituted carboxylic acids in high ee.
[GRAPHICS]The ene reaction of singlet oxygen with chiral trisubstituted alkenes bearing an alkyl and a phenyl group at the stereogenic center is erythro diastereoselective in solution and threo diastereoselective if carried out within zeolite Na-Y. The change of the diastereoselection trend by zeolite confinement is attributed to a synergism of steric effects and cation-pi interactions.
An Enantioselective Route to α-Methyl Carboxylic Acids via Metal and Enzyme Catalysis
Dynamic kinetic resolution of allylic alcohols to allylic acetates followed by copper-catalyzed allylic substitution gave alkenes in high yields and high optical purity. Subsequent oxidative C-C double bond cleavage afforded pharmaceutically important alpha-methyl substituted carboxylic acids in high ee.