Synthesis and characterization of multidimensional supramolecular networks supported by multitopic tris(pyrazolyl)methane ligands

The development and synthesis of several new multitopic ligands based on tris(pyrazolyl)methane donor units and their use in the synthesis of multidimensional supramolecular architectures is discussed. The strategy here consist of using non-covalent forces such as weak hydrogen bonds, C--H ··· pi interactions or pi - pi stacking to influence the outcome of the covalently bonded networks. Based on this approach, a non-covalent strategy for the assembly of covalent networks was established. The same non-covalent driving forces can be used to induce a specific crystal packing of discrete cage-like supermolecules.;The robustness of non-covalent forces within this system will also be addressed. A combination of X-ray crystallography, IR spectroscopy, DFT calculations and ES/MS studies have been used to investigate the solid state and solution properties of silver(I) complexes formed from closely related semi-rigid, multitopic ligands, one of which is tetratopic and the other two bitopic analogs that can each be viewed as possessing half of the bonding properties of the first. The covalent and supramolecular structures of the silver(I) complexes based on this type of ligands are surprisingly similar, both being organized in a comparable architecture by the same non-covalent forces.