Crystal structure of N-[3-(dimethylamino) propyl]-N ', N ', N '', N ''-tetramethyl-N-(N,N,N ', N '-tetramethylformamidiniumyl) guanidinium bis(tetraphenylborate)

In the title salt, C15H36N62+ center dot 2C(24)H(20)B(-), the three N-C bond lengths in the central C3N unit of the bisamidinium ion range between 1.388 (3) and 1.506 (3) angstrom, indicating single-and double-bond character. Furthermore, four C-N bonds have double-bond character. Here, the bond lengths range from 1.319 (3) to 1.333 (3) angstrom. Delocalization of the positive charges occurs in the N/C/N and C/N/C planes. The dihedral angle between both N/C/N planes is 70.5 (2)degrees. In the crystal, CH center dot center dot center dot pi interactions between H atoms of the cation and the benzene rings of both tetraphenylborate ions are present. The benzene rings form aromatic pockets, in which the bisamidinium ion is embedded. This leads to the formation of a two-dimensional supramolecular pattern along the ab plane.