Ruthenium(II)-Catalyzed Tandem C-H Allylation and [3+2] Dipolar Cycloaddition to Construct Bridged Tetracycles

The ruthenium(II)-catalyzed tandem C-H allylation and intramolecular dipolar cycloaddition between azomethine imines and 2-methylidenetrimethylene carbonate is described herein. The initially formed beta-substituted allyl fragment could trigger the exotype [3 + 2] cycloaddition with the polar azomethine group, resulting in the formation of bridged tetracydes bearing a hydroxymethylene group at a bridgehead carbon center. A wide substrate scope and broad functional group compatibility were observed. The gram-scale synthesis and synthetic transformations demonstrate the synthetic utility of this process.

Automated summary

This paper describes the ruthenium(II)-catalyzed tandem C-H allylation and intramolecular dipolar cycloaddition reaction, which can form bridged tetracycles bearing a hydroxymethylene group at a bridgehead carbon center. The reaction exhibits a wide substrate scope and broad functional group compatibility.