Alkoxy- and Aryloxy-derivatives

Alkoxy- and Aryloxy-derivatives.—The preparation and physical properties of a series of thermally stable monoalkoxy (or aryloxy) fiuoro-cyclophosphazenes have been reported  

Thiolysis by NaSR under the same conditions gave N3P3F5SR (R = Me or Ph). Ligand-exchange reactions between a series of organo-substi-tuted cyclotriphosphazatrienes have been studied and their synthetic potential demonstrated. Typical of these reactions is  

An order of reactivity for a series of nucleophiles towards a given substrate could be drawn up and, in general, this follows the order  

The lability of certain alkoxy-groups has also been shown in the reactions  

Similar reactions with heptafluorobutoxy-derivatives have also been demonstrated. 

Alkoxy- and Aryloxy-derivatives.—A series of spirocyclophosphazenes has been prepared from the reactions of 1,8-dihydroxynaphthalene with 

Chivers and R. Hedgeland, Inorg. Nuclear Chem. Letters, 1971, 7, 767. T. Chivers and R. Hedgeland, Canad. J. Chem., 1972, 50, 1017. 

Rate measurements have been carried out on the reaction of N3P3CI6 with benzyl alcohol, which gives two different sets of products, e.g. 

The benzoyloxychloro-derivatives N3P3Cl6- (OCH2Ph) ( = 1—5) were isolated and structural assignments made from their and P n.m.r. spectra. 

Although alkoxyphosphazenes rearrange to oxophosphazanes, there was no evidence that the analogous rearrangement  

The preparation of alkoxy-derivatives of cyclic phosphazenes such as N3P3(OPrn)6 has been described in two patents,126 127 and alkoxyphosphazenes [NP(OAlk)2]3l4,fi have been separated by g.l.c.128 

Hydrolysis of these compounds only starts in alkali at 140—160 °C, to give products which are probably present as a mixture of tautomeric forms (56) and (57). Detailed consideration has been given to the role of intermediates in the degradation of 

N3P3C16 to phosphoranes by or/Ao-dinucleophiles such as o-aminophenol and catechol.130 Thus it has now been shown that the intermediate (58), in the formation of (59), can be isolated from reactions with the former dinucleophile, but (58) is more conveniently isolated from the reaction of non-geminal N3P3Cl3(NMe2)3 with o-aminophenol. 

Reactions with several other dinucleophiles have been studied. These include NaOC6H4CHaOH-o, which gives N3P3(OC6H4CH2OH-o) C16-w (n — 2, 3, 4, 6), the latter of which was the precursor of a condensation polymer.131 Salicylic acid in the presence of triethylamine gives (60), which can be sublimed to give (61).132 Aliphatic and aromatic aldoximes can be converted into nitriles by reaction with 

N3H3P303(0H)3C1CH2SCH3 -U- N3P3Cl3(OH)3ClCH2SCH3 Reagent i, DMSO. 

More unusual alkoxy-derivatives of N3P3CI6 are formed in the reactions with sodium salts of cellulose, which obey second-order kinetics, and in copolymers derived from arabinose, the latter being hydrolysed by alkaline phosphatase. By contrast, (95) is not hydrolysed by this phosphatase. Relative basicity measurements,obtained from the i.r. spectra of cyclophosphazenes mixed with phenol, show that fluoroalkoxy-derivatives N3P3(ORp)6 are more basic than NaPaClg. 

Molecular motion and molecular separations in cyclophosphazene clathrates form the subject of an A -ray crystallographic and a wide-line n.m.r. study. The latter technique was used to assess the relative degree of molecular motion of benzene or /7-xylene in the compounds (96) (see Section 8 for A -ray information). 

In connection with studies of the relative reactivities of cyclotriphospha-zenes, a large number of pentakisaryloxy-derivatives NaPaCKOArls have been 

spectra of some of these derivatives were reported, and basicity measurements discussed. The major product from the ammono-lysis of the non-geminal triphenoxy-derivative NsPaClafOPhja is NaPjCl-(NH2)2(OPh 3. The triamino-derivative N3P3(NH2)3(OPh 3 was only obtained in 5% yield.  

The reactions of the alkoxycyclophosphazenes [NP(OCH2CF3)a]3,4 with diphenyl ketone result in the formation of the acid (CF8CHa0)2P(0)(0H) and organic imines. The cyclophosphazene N3P3CI6 (and N4P4CI8) reacts with formamide and thioformamide to give metaphosphimic and metathiophos-phimic acids, respectively. These acids appear to be in tautomeric equilibrium, e.g. 

The thioalcoholysis of N4P4CI8 generally results in the replacement of four chlorine atoms to give derivatives of probable structure (42), based on evidence 

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The synthesis and properties of cyclodiphosphazatrienes of type (49) and (50) are well documented. A series of P-alkoxy- and-aryloxy-derivatives... 

Alkoxy- and Aryloxy-derivatives.—The cyclophosphazene (90) undergoes the reactions with alcohols and with sodium alkoxides that are shown in Scheme 9. The... 

The polymeric product with R = R = Me is fully characterized. An average molecular weight of 50 000 has been reported which corresponds with n 660. A widely adopted approach for preparing organophosphazene polymers is the nucleophilic substitution of chlorine atoms in uncross-linked (NPCla). Much attention has been paid to alkoxy and aryloxy derivatives being stable polymers. Examination of reactions between (NPCl2) and NaOCHaCFa shows hydrolysis... 

Many reactions are known in which the halogen atoms of halophosphazenes can be wholly replaced by other atoms or groups. Thus replacement by hydroxyl can be effected by hydrolysis to give [PN(0H)2] , and by amine groups to give [PN(NH2)2] . Alkoxy and aryloxy derivatives can be... 

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