Disilanes with Pentacoordinate Si Atoms by Carbon Dioxide Insertion into Aminodisilanes: Syntheses, Molecular Structures, and Dynamic Behavior

The insertion of carbon dioxide into the Si-N bonds of aminodisilanes ((RR'N)(n)Me3-nSi)(2) affords carbamoyloxydisilanes ((RR'NC(O)O)(n)Me3-nSi)(2). Some of the obtained insertion products feature pentacoordinate silicon atoms in the solid state and in solution, with two carbamoyloxy moieties bridging the Si-Si bond. The amino-disilanes and their insertion products were extensively analyzed, including single-crystal X-ray structure analyses. The temperature dependence of the higher coordination was investigated using variable temperature NMR experiments.