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.