6607-30-3Relevant academic research and scientific papers
Synthesis and reactivity of phosphine-stabilized phosphoranimine cations, [R3P·PR′2=NSiMe3]+
Huynh, Keith,Lough, Alan J.,Forgeron, Michelle A. M.,Bendle, Martin,Soto, Alejandro Presa,et al.
experimental part, p. 7905 - 7916 (2009/10/16)
A series of phosphine-stabilized phosphoranimine cations [R 3 P·PR′ 2 =NSiMe 3 ] + , which canbe regarded as derivatives of the proposed transient reactive intermedi ate [PR′ 2 =NSiMe 3 ] + in the thermalcondensation polymerization of phosphoranimines (R″O) PR′2 =NSiMe 3 to form poly(alkyl/arylphosphazenes) [PR′ 2 =N] n at 180-200°C, have been prepared. The bromide salts [R 3 P·PR′ 2 =NSiMe 3 ]Br [R′ = Me ([6] + ), OCH 2 CF 3 ([8] + ); R 3 P = Me 3 P (a), Et 3 P (b), n Bu 3 P (c), dmpm (d, dmpm = dimethylphosphinomethane), dmpe (e, dmpe = dimethylphosphinoethane)] were prepared from the direct reactions between BrMe 2 P=NSiMe 3 (5) and Br(CF 3 CH 2 O) 2 P=NSiMe 3 (7)and the corresponding tertiary phosphines R 3 P or the diphosp hines Me 2 P(CH 2 ) n PMe 2 (n = 1, 2). Cations of the type [6] + and [8] + , with electron-donating and -withdrawing groups at the phosphoranimine phosphorus center, respectively, undergo facile phosphine ligand substitution with the strong N-donor 4-dimethylaminopyridine (DMAP) to yield the corresponding DMAP-stabilized salts [DMAP·PR 2 =NSiMe 3 ]Br [R = Me ([9] + ), OCH 2 CF 3 ([10] + )]. Cations [6] + with Br - anions are particularly labile: for example, [6a]Br slowly releases PMe 3 , BrSiMe 3 , and forms cyclic phosphazenes such as [Me 2 P=N] 4 . Anion exchange reactions between the salts [6b]Br or [8c]Br and AgOTf (OTf = CF 3 SO 3 ) quantitatively afforded the corresponding and more stable triflate salts [6b]OTf and [8c]OTf.Phosphine ligand abstraction reactions with B(C 6 F 5) 3 were observed for the bromide salts [6b]Br and [8c]Br, which regenerated the phosphoranimines 5 and 7, respectively, and formed the adduct R 3 P·B(C 6 F 5 ) 3 . In contrast, the triflate salts [6b]OTf and [8c]OTf were unreactive under the same conditions. X-ray structural analysis of the P-donor stabilized cations revealed longer P-P and P-N bond lengths and smaller P-N-Si bond angles for cations [6] + compared to analogs [8] + . These structural differences were rationalized using the negative hyperconjugation bonding model. In addition, the ...
RING SYSTEMS DERIVED FROM N-SILYLPHOSPHORANIMINES
Neilson, R. H.,Azimi, K.,Davis, C. E.,Hani, R.,Jinkerson, D. L.,et al.
, p. 317 - 320 (2007/10/02)
The N-silylphosphoranimines, Me3SiN=PR2X, undergo a variety of useful reactions such as condensation polymerization, Si-N bond cleavage, nucleophilic substitution at phosphorus, and deprotection of pendent P-methyl group.Several ring systems, including cyclic phosphazenes and novel B-N/P-N hybrid derivatives, are accessible from these Si-N-P reagents.
Substitution reaction of hexachlorocyclotriphosphazene with trimethylaluminum
Jackson, Logan A.,Harris, Paul J.
, p. 4338 - 4343 (2008/10/08)
The reaction of hexachlorocyclotriphosphazene with trimethylaluminum yields the fully substituted hexamethylcyclotriphosphazene and a ring-opened linear phosphazene salt. The substitution pathway that yields the fully substituted cyclic product was determined by monitoring the reactions of several methylchlorocyclotriphosphazenes with trimethylaluminum with the use of gas chromatography and 31P NMR spectroscopy. The reaction was found to proceed via both geminal and nongeminal substitution pathways, depending on the species undergoing substitution. The degree of ring opening that occurred was observed to decrease with increasing methyl substitution of the phosphazene ring. The new products prepared were characterized by 1H, 13C, and 31P NMR spectroscopy, infrared spectroscopy, mass spectrometry, and elemental analysis.
