Ring-Closing Metathesis/Isomerization/Pictet–Spengler Cascade via Ruthenium/Chiral Phosphoric Acid Sequential Catalysis

Quan Cai , Xiao-Wei Liang , Shou-Guo Wang , Jun-Wei Zhang , Xiao Zhang , and Shu-Li You *

http://pubs.acs.org/doi/abs/10.1021/ol302215u


Just a nice idea to generate polycyclic frameworks.  The added chiral phosphoric acid (substoichiometric) induces the requisite post-metathesis isomerization and allows the final Pictet-Spengler step to proceed in a highly stereoselective way.