Triethyamine-promoted [5+3] Cycloadditions for Regio- and Diastereoselective Synthesis of Functionalized aza-Bicyclo[3.3.1]alkenones

We have developed a synthetic strategy for Et3N-promoted [5+3] cycloaddition reactions between acetoxypyranones and azomethine imines to access functionalized azabicyclo[3.3.1]alkenones with three tertiary stereocenters (31 examples, 36% to 87% yield, 5.5:1 to >20:1 dr). The method was scalable, and the products could be transformed to various eight-membered-ring bridged heterocyclic molecules.

Automated summary

A synthetic strategy for accessing functionalized azabicyclo[3.3.1]alkenones with three tertiary stereocenters has been developed. The method is scalable and the products can be transformed to various eight-membered-ring bridged heterocyclic molecules.