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A series of closely related polyphosphazenes with propoxy, pentoxy, hexoxy, octoxy, isostearyloxy, and 2-(2-methoxyethoxy)ethoxy (MEE) side groups, together with cosubstituent species with both the alkoxy and MEE side chains, were studied for their morphology and miscibility with oligoisobutylene (OIB). All the pure polymers except one had a single glass transition temperature. The exception was the species with both isostearyloxy and MEE side groups, which underwent two low-temperature second-order transitions, even though 31P NMR spectra indicated the absence of a block-type structure. For the single-substituent macromolecules, the solubility at 80 ° C in OIB increased as the length of the unbranched alkoxy side groups rose from propoxy to octoxy (from 1 to 11 wt/wt%). However, the polymer with two isostearyloxy side chains per repeat unit had a low solubility in OIB (3 wt/wt%), and the species with the two MEE side groups on every repeat unit was totally insoluble. When both alkoxy and MEE side groups were present, the solubility in OIB was also low (0-3%), except for the species with both isostearyloxy and MEE side groups, which was soluble in OIB at a level of 21 wt/wt% at 80 ° C, and showed Tg evidence of polymer/oligomer miscibility even at -80 ° C. Explanations are suggested for the unusual behavior of this polymer. POLYM. ENG. SCI., 51:1693-1700, 2011. ©2011 Society of Plastics Engineers, INTRODUCTION Polyphosphazenes are hybrid inorganic-organic macromolecules in which the properties are determined by both the inorganic phosphorus-nitrogen backbone and the organic side groups. The backbone imparts properties such as fire [...]

The mechanism of the aza-Wittig reaction between phosphazenes and aldehydes is studied computationally using density functional theory methods. It is found that the reaction consists of a tandem [2+2] cycloaddition-cycloreversion sequence in which pi and sigma orbitals as well as lone pairs are involved.

Variable-temperature (super 2)H NMR investigations are carried out to study the molecular behavior of predeuterated benzene in the inclusion compound with tris(1,2-dioxyphenyl)cyclotriphosphazene. A quantitative analysis of the experimental data is achieved by appropriate computer simulations taking into account various motions of the benzene guests.

Triphosphazene, 1,3,5-triazo-2,4,6-triphosphorine-2,2,4,4,6,6-chloride (TAPC), has served as an efficient catalyst for the Beckmann rearrangement of ketoximes to lactams. The rearrangement of cyclohexanone oxime to [epsilon]-caprolactam is achieved by TAPC and this method has provided an environmental friendly route to nylon-6 without formation of any salt.

A two-step asymmetric synthesis of disubstituted N-tosyl aziridines is presented using a phosphane base. This two-step asymmetric synthesis could be easily used on gram quantities and involves no unstable/hazardous reagent.