Synergistic Catalysis: Enantioselective Ring Expansion of Vinyl Cyclopropanes Combining Four Catalytic Cycles for the Synthesis of Highly Substituted Spirocyclopentanes Bearing up to Four Stereocenters
作者:Marta Meazza、Ramon Rios
DOI:10.1002/chem.201601893
日期:2016.7.11
A double synergistic cascade reaction is reported, combining transition metal and amine catalysis. The reaction between vinyl cyclopropanes and enals renders the final cyclopentane derivatives in excellent yields and stereoselectivities.
The stereoselective [3 + 2] cycloaddition between vinylcyclopropanes and α,β-unsaturatedaldehydes promoted by combined palladium and organocatalysis is disclosed. The unique synergistic catalytic system allows for the stereoselective formation of highly substituted cyclopentanes with up to four stereocenters in high yields and selectivities. Vinylcyclopropanes with two different geminal substituents