Publication Details (including relevant citation information):
Bowers, David J., Wright, Brian D., Scionti, Vincenzo, Schultz, Anthony, Panzner, Matthew J., Twum, Eric B., Li, Lin-Lin, Katzenmeyer, Bryan C., Thome, Benjamin S., Rinaldi, Peter L., Wesdemiotis, Chrys, Youngs, Wiley J., Tessier, Claire A. Inorganic Chemistry 2014 53 (17) 8874-8886
Abstract: Medium-sized cyclic oligomeric phosphazenes [PCl2N]m (where m = 5?9) that were prepared from the reaction of PCl5 and NH4Cl in refluxing chlorobenzene have been isolated by a combination of sublimation/extraction and column chromatography from the predominant products [PCl2N]3 and [PCl2N]4. The medium-sized rings [PCl2N]m have been characterized by electrospray ionization?mass spectroscopy (ESI-MS), their 31P chemical shifts have been reassigned, and their T1 relaxation times have been obtained. Crystallographic data has been recollected for [PCl2N]5, and the crystal structures of [PCl2N]6, and [PCl2N]8 are reported. Halogen-bonding interactions were observed in all the crystal structures of cyclic [PCl2N]m (m = 3?5, 6, 8). The crystal structures of [P(OPh)2N]7 and [P(OPh)2N]8, which are derivatives of the respective [PCl2N]m, are also reported. Comparisons of the intermolecular forces and torsion angles of [PCl2N]8 and [P(OPh)2N]8 with those of three other octameric rings are described. The comparisons show that chlorophosphazenes should not be considered prototypical, in terms of solid-state structure, because of the strong influence of halogen bonding.
Address (URL): http://dx.doi.org/10.1021/ic500272b