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We examine the use of thionylphosphazene-based block copolymers as matrixes for oxygen sensor applications. Poly(aminothionylphosphazene)-b-poly(tetrahydrofuran) (PATPy-PTHFx) block copolymers were prepared via reaction of ring-opened poly(chlorothionylphosphazene) with THF and subsequently with excess n-butylamine (to form PBATPy-PTHFx) or methylamine (to form PMATPy-PTHFx). The block copolymers were characterized by NMR, gel permeation chromatography, and differential scanning calorimetry. Films of PBATPy-PTHFx block copolymers containing platinum octaethylporphyrin or [Ru(dpp)3]Cl2 (dpp = 4,7-diphenyl-1,10-phenanthroline) as the oxygen-sensitive chromophore were prepared, and time-scan experiments were carried out to determine the diffusion coefficients, Do2, and solubilities, So2, of oxygen therein. Despite microphase separation, the data fit well to a simple Fick's law description of oxygen diffusion and gave Do2 values smaller than that for the n-butylamino-substituted PBATP635. For films freshly annealed above the melting point of PTHFx, the Do2 values were 35-50% (dye-dependent) larger than after aging 3 days at room temperature. Films with [Ru(dpp)3]Cl2 as the dye were evaluated as media for phosphorescent pressure-sensing. The dye-containing polymer films exhibit linear Stern-Volmer-like plots, even at high dye concentrations, as well as good photostability, and significantly higher sensitivity to oxygen quenching than simple mixtures of the analogous homopolymers.

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The structural characterization of the boratophosphazene N-(PCl 2 NMe) 2 BCl 2 (1) is reported and reveals a distorted structure in which the boron atom is bent out of the plane of the other ring atoms (0.39 (1) show the presence of planar rings with B ± N bond lengths (ca.

The thionylphosphazene cation [NSO(NPCl2)2]+ is a proposed intermediate in the thermal ring-opening polymerization of the cyclic thionylphosphazene NSOCl(NPCl2)2 (1) at 165 °C. The attempted generation of [NSO(NPCl2)2]+ via halide abstraction from 1 with a variety of Lewis acids has been studied and the possible intermediacy of this species in the subsequent reactions is suggested by the products isolated. The thermal reaction of 1 with 2 equivalents of AlCl3 at 80 °C in 1,2-dichloroethane led to the quantitative formation of NSO(CH2CHCl2)(NPCl2)2; reaction of 1 with Ag[BF4] at 25 °C afforded the sulfur(VI)-fluorinated species NSOF(NPCl2)2 and the treatment of 1 with Ag[OSO2CF3] resulted in the quantitative formation of NSO(OSO2CF3)(NPCl2)2; the latter species was found to cleave diethyl ether and generate NSO(OCH2CH3)(NPCl2)2. Ambient temperature reaction of 1 with GaCl3, AlCl3 or SbCl5 (10:1), produced the high molecular weight poly(thionylphosphazene) [NSOCl(NPCl2)2] n and, in addition 12-, 18-, 24- and higher-membered macrocycles. Studies showed GaCl3 as the most effective ROP initiator, and AlCl3 the least. Subsequent reaction of [NSOCl(NPCl2)2]n with n-BuNH2 yielded the hydrolytically stable poly(aminothionylphosphazene) [NSO(NHBu){NP(NHBu)2}2] n , which possessed molecular weights in the range, M n = 25 000−60 000; PDI = 1.26−2.88. The polymerization reaction studied represents the first example of the ambient temperature ROP of any phosphazene or heterophosphazene ring induced by the deliberate addition of an initiator. Interestingly, the concentration of monomer 1 in solution was found to have a dramatic influence on the extent of reaction and the product distribution. Concentrated solutions of 1 and GaCl3 (10:1) afforded only [NSOCl(NPCl2)2] n and larger macrocycles, whereas more dilute solutions afforded [NSOCl(NPCl2)2] n together with smaller macrocyclic products with lower conversions. Remarkably, dilute solutions of 1 were found to be unreactive toward GaCl3. This existence of a critical equilibrium concentration (∼0.15 M) below which the monomer does not polymerize has only rarely been observed for inorganic systems and is indicative of a polymerization with a small ΔH value which implies that heterocycle 1 is not very strained.

The reaction of TaCl5 with a single equivalent of Cl3P=NSiMe3 resulted in the isolation of the perhalogenated (phosphoraniminato) tantalum(V) complex TaCl4(N=PCl3) (1). Reaction of 1 with an excess of THF and subsequent cooling produced crystals of TaCl4(N=PCl3)(THF) (1.THF), which possesses a distorted octahedral Ta center with a THF molecule coordinated trans to the phosphoraniminato ligand. The reaction of 1 with the aminophosphoranimine, (Me3Si)2NPCl2=NSiMe3, resulted in a [3 + 1] cyclocondensation reaction to form the metallacyclic complex, TaCl3(N=PCl3)[N(SiMe3)PCl2N(SiMe3)] (2), which contains a TaNPN four-membered ring and a phosphoraniminato ligand (N=PCl3). The analogous [3 + 1] cyclocondensation reaction between (Me3Si)2NPCl2=NSiMe3 and TaCl5 led to the isolation of TaCl4[N(SiMe3)PCl2N(SiMe3)] (3). An attempt to cleave the NPN ligand from the Ta center in 2 via protonolysis with HCl led to an unusual phosphoraniminato ligand coupling reaction to yield the novel phosphazenium salt [N(PCl2NH2)2][TaCl6] (4). All new compounds (1.THF and complexes 1-4) were characterized by single-crystal X-ray diffraction.

There are two mol­ecules in the asymmetric unit of the title compound, C4H13NO2SSi. In the crystal, mol­ecules are linked via inter­molecular N—H⋯O hydrogen bonds, forming chains along [001]. The crystal studied was an inversion twin, the refined ratio of twin domains being 0.61 (9):0.39 (9).

Aminolysis of the chlorinated poly(thionylphosphazene) [NSOCl(NPCl2)2]n (2a) with several secondary amines NHR2 (diethylamine, piperidine, and pyrrolidine) yielded various hydrolytically stable poly[(amino)thionylphosphazenes] [NSO(NR2){NP(NR2)2}2]n 6 (a, NR2 ) piperidine; b, NR2 ) pyrrolidine) in which chlorine atoms at both the phosphorus center and sulfur were replaced. In addition, treatment of 2a with different equivalents of several secondary amines (diethylamine, piperidine, and pyrrolidine), followed by addition of excess of n-butylamine, lead to a series of mixed-substituent poly[(amino)thionylphosphazenes] [NSO(NHR′){NP(NR 2)2}2]n 7 (NHR′ ) n-butylamine; a-c, NR2 ) diethylamine; d, e, NR2 ) piperidine; f, NR2 ) pyrrolidine). The new moisture stable polymers were characterized by 31 P, 13 C, and 1 H NMR spectroscopy and elemental analysis. The molecular weights of the polymers 6a,6b and 7a-7f were in the range of M h w ) 3.4 × 10 4 -1.1 × 10 5 and M h n ) 3.1 × 10 3 -5.0 × 10 4 according to GPC analysis in THF versus polystyrene standards. The thermal transition behavior was investigated by means of DSC. Glass transition temperatures (Tg's) of the poly[(amino)thionylphosphazenes] 6a,6b and 7a-7f depend on the content of secondary amine versus primary amine and were in the range of -13 to +27 °C. No melt transitions were detected.