TfO-•••H-O-H Interaction-Assisted Generation of a Silicon Cation from Allylsilanes: Access to Phenylallyl Ferrier Glycosides from Glycals

We demonstrate here that the strained and bulky protonated 2,4,6-tri-tert-butylpyridine (TTBPy) triflate salt serves as a mild and efficient organocatalyst for the diastereoselective C-Ferrier glycosylation of various glycals. The importance of the role of the 1/2 H2O molecule trapped in the catalyst has been disclosed. The mechanism of action involves unique anionic triflate and H2O hydrogen-bond interactions that assist the activation of allylsilanes, providing unprecedented access to diastereoselective phenylallyl Ferrier glycosides.

Automated summary

This study demonstrates the application of strained and bulky protonated TTBPy triflate salt as a mild and efficient organocatalyst in diastereoselective C-Ferrier glycosylation, and reveals the importance of the trapped H2O molecule in the catalyst. The mechanism involves unique anionic triflate and H2O hydrogen-bond interactions that activate allylsilanes, providing unprecedented access to diastereoselective phenylallyl Ferrier glycosides.