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An effective route to the oxidation of organic derivatives of trivalent phosphorus with an aqueous solution of hydrogen peroxide was considered. Phenylphosphonites, including those having a hydrolytically unstable phosphorus-nitrogen bond were involved into the oxidation. The identification of oxidation products, the phenylphosphonates, was carried out using the method of ion cyclotron resonance mass spectrometry with Fourier transform combined with electrospray ionization, and by 31P and 1H NMR spectroscopy. The influence of an effective antioxidant of natural origin, quercetin, on the oxidation was demonstrated.

Interaction between the equimolecular amounts of glycols (diatomic phenols) and phosphorous acid triamides in diglyme or without solvent gives phosphorus-bearing polyamidophosphites. The structure of these compounds was studied by NMR spectroscopy, and it was shown that a partial disproportionation of amidophosphite fragments into phosphite ones can occur in the course of their synthesis. The chemical properties of the obtained compounds are being studied. First rhodium complexes with polyamidophosphite ligands were obtained. These complexes are shown to be more active hydrogenation catalysts than the corresponding low-molecular complexes. 1

The data of temperature-programmed desorption of ammonia from the surface of oxide systems and IR spectroscopy were used to demonstrate that the strength of the surface acid sites in titanium oxides prepared by the alkoxo method and modified by aluminum decreases with respect to that in nonmodified titanium oxide. Modification of titanium oxide with P3+ ions from ethriol phosphite almost completely suppresses the acid properties. Modified oxides are able to chemisorb water. XANES data suggest that modification of titanium oxide with phosphorus ions increases the electron density on the titanium atoms and, correspondingly, the basicity of the materials.

Hexaalkylphosphorous triamides form in good yields 6-dialkylamino-12H-dibenzo[d.g] [1,3,2]dioxaphosphocins 2a-i in the reaction with oligophenols 1a-i. Heating the stencal hindered compounds 2a-f up to 315°C leads to the corresponding bicyclic phosphites 3a-d while the non-hindered phosphocins 2g-i react in refluxing xylene to give phosphites 3e-g. The phosphocin 2i formed another phosphocin 2i* during heating to 90°C in THF by “wandering” of the phosphorus moiety. The bicyclic phosphites 3h and 3i were prepared starting from tetraphenol 1h and pentaphenol 1i by reaction with hexaethylphosphorous triamide in refluxing xylene. The diphosphorylated triphenol 4 and tetraphenol 5 are formed in the reaction of the corresponding phenols with 2 eq. of hexaalkylphosphorous triamide.

The formation of adducts in the system containing Rh2(OAC)4, cyclic amidophosphite [El2NPO(CH2)3O] and bicyclic phosphite [P(OCH2)3CEt] have been studied using low temperature 31P NMR. Varying the concentration of Rh2(OAc)4 made the signals due to a mono-adduct, a homoligated bis-adduct and a mixed bis-adduct observable in the 31P spectra. Iterational optimisation of the parameters of the spectra of symmetric bis-adducts showed a very strong correlation between the values of the coupling constants 1JRhRh and3JPP. The spectrum of the asymmetric adduct (amidophosphite-Rh-Rh-phosphite) yielded a well defined estimate of 3JPP. This value (793 Hz) is found to be between the values of the coupling constants for phosphite-phosphite and phosphite-phosphine interactions found by Boyar and Robinson. The integrals of the lines in the 31P spectra of the samples derived from different starting concentrations of Rh2(OAc)4 yielded values for the stability constants of the detected adducts. The mono-adduct of amidophosphite was found to be significantly more stable than that of phosphite.

A bicyclic phosphite, 4-ethyl-2,6,7-trioxa-1-phosphabicyclo [2.2.2]octane (1) was used for the complex formation with dirhodium(II) tetraacetate. Under the mole ratio P/Rh2 = 2, the reaction leads to an axial adduct (AcO)4Rh2L2. An excess of the phosphite (P/Rh2 = 20) causes the rupture of the metalmetal liaison, reduction of Rh(II) to Rh(I), and formation of a coordinatively unsaturated complex (RhL3)+ AcO−, which presents a new phenomenon. The complex was identified by low-temperature 31P NMR spectroscopy.

The paper is concerned with rhodium(1) complexes of the type acacRh(CO)L, Rh(CO)ClL2, [Rh(CO)LCl]2, [acacRh(CO)[2L and [Rh(CO)LCl]n, where L: P are monodentate, P,N- and P,P-bidentate ligands including 1,3,2-diheterophospholane and phosphorinane cycles In our studies two synthetic approaches were used, viz. the interaction of tricoordinated phosphorus derivatives with the starting rhodium substrate proceeding via the associative mechanism and the reaction of pentacoordinated phosphorus derivatives (hydrospirophosphoranes) 31P, 1H, 13C NMR, IR spectroscopy as well as X-ray and chemical studies of rhodium-coordinated 1,3,2-diheterophos-phacyclanes were carried out. The properties of these organophosphorus ligands were shown to depend on the nature and configurational rigidity of the substituents X, Y, Z at the phosphorus atom. This is illustrated by the dependence of 1J(Rh, P) and ν (CO) on the size of the phosphorus ring and the position of the heteroatoms (O, N) in the ligand molecule.