Highly Stereoselective [4 + 3] Cycloadditions of Nitrogen-Stabilized Oxyallyl Cations with Pyrroles. An Approach to Parvineostemonine†

A highly stereoselective [4 + 3] cycloaddition of N-substituted pyrroles with allenamide-derived nitrogen-stabilized chiral oxyallyl cations is described here. This method provides an approach for constructing tropinone alkaloids.