Intramolecular Inversion of Configuration at Tetrahedral Carbon Centres in Dipolar Spiro-σ-Complexes of Amino-, Diamino- and Aminothiotropones: a Dynamic NMR Spectral Study

Inversion of configuration at the tetrahedral carbon centres of dipolar spiro-σ-complexes formed by coupling 2-(N-benzylamino)tropone, 2-(N-benzylamino)thiotropone or N,N’-dibenzyl-2-aminotroponimine with electrophilic aromatic and heterocyclic compounds has been found to occur intramolecularly with energy barriers accessible to measurement by means of dynamic ¹H NMR spectral techniques.