Two C2-symmetric chelating P2-bisphosphazene superbases connected via a binaphthyl backbone - synthesis, structural features and preparation of a cationic alkyl aluminum complex

Two P-2-phosphazenyl groups were linked via a C-2-symmetric binaphthyl backbone resulting in two novel chiral superbases with dimethylamino and pyrrolidino substituents. We investigated their basic properties and coordination chemistry towards a cationic alkyl aluminum fragment. The outstanding basicity of the chiral tetrasphosphazenes presented herein leads to interesting perspectives for application in asymmetric Bronsted base catalysis.