Tetraorganopnictonium and Alkali Metal Salts of Pyridine-2,6-di-tetrazolate

Alkali metal (Na, K) and tetraorganopnictonium (AsPh4, PPh4) salts were prepared from 2,6-bis(1H-tetrazol-5-yl)pyridine (H(2)pydtz) and characterized by multinuclear NMR, IR, and UV/Vis absorption spectroscopy. Single crystal XRD of (AsPh4)(2)(pydtz)center dot 5H(2)O reveals isolated pydtz(2-) dianions sandwiched between two AsPh4+ cations and an interesting hydrogen bridging network comprising the five co-crystallized water molecules and the three pydtz N atoms. (PPh4)(2)(pydtz)center dot 5H(2)O is isostructural to (AsPh4)(2)(pydtz)center dot 5H(2)O as revealed from powder XRD measurements and corresponding Rietveld fits. The crystal structure of the mixed salt Na-3(PPh4)(pydtz)(2)center dot 12H(2)O reveals pi-stacking interaction of the pydtz(2-), a polymeric chain of water molecules and Na+ cations in an extended hydrogen bonding and Na+-coordinating network. PPh4+ cations interact solely through their positive charge. The alkali metal salts were soluble in water, alcohols, and DMF, whereas the pnictonium salts were additionally soluble in less polar solvents such as acetone, DMSO, CH2Cl2, or THF