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Hydroxyapatite was synthesized in conditions of mechanoacoustic treatment of an aqueous reaction mixture consisting of ammonium hydrogen phosphate and calcium nitrate using a commercially available rotary pulsation apparatus. Mechanoacoustic treatment of the reaction mixture was found to lead to the formation of nanosized hydroxyapatite particles with a predominant mean diameter of about 20 nm. Purification of technical hydroxyapatite to remove traces of ammonium nitrate by thermal processing at 350°C is proposed. The crystalline phase of hydroxyapatite was found not to be dominant in the structure. The porosity of hydroxyapatite amounted to about 75% with a mean pore diameter of 2.8 × 103 nm. Thermal processing of hydroxyapatite in aqueous medium was found to yield a paste-like form. Hydroxyapatite paste had no cytotoxicity and did not prevent cell adhesion, though it almost completely inhibited cell spreading.

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.

Condensing phosphorylation of 1,6-hexanediol, 1,4-dihydroxybenzene, 4,4′-dihydroxybiphenyl, and 2,2-bis(4′-hydroxyphenyl)propane by phenylphosphonous acid tetraethylamide was effected by treatment of the disperse reaction system with high-frequency sound. This treatment ensures efficient shift of the phase equilibrium in the course of condensation and increases the yield of phenylphosphonous acid oligoesters.

Step high-temperature condensation of dihydric phenols [1,4-dihydroxybenzene, 4,4′-dihydroxybiphenyl, and 2,2′-bis(4-hydroxyphenyl)propane] with phenylphosphonous bis(diethylamide) is carried out. The molecular weight, composition, and structure of the resulting oligomeric arylene phenylphosphonites were assessed by means of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The widest mass range was observed in the mass spectrum of 4,4′-dihydroxybiphenyl, which corresponds to an oligomer having about 30 elementary units. The obtained data agree with the the molecular weight measured by high-speed sedimentation. The reactions of phenylphosphonous bis(diethylamide) with dihydric phenols give both acyclic and cyclic arylene phenylphosphonites.

A representative of the new class of organophosphorus ligands, viz., o,o"-dimethylene(tri-p-cresyl) bicyclophosphite (BCP), was studied as a promoter of Rh(acac)(CO)2 in hydrogenation and hydroformylation. BCP enhances the activity and stability of the catalyst much more strongly than analogous organophosphorus ligands used previously (triphenylphosphine, triphenyl phosphite, and etriolphosphite). A reason for this behavior of BCP was studied using NMR spectroscopy, quantum-chemical calculations, and molecular simulation. The high sensitivity of the 1H NMR signals of the methylene groups of BCP toward complexation appears due to the high density of the highest occupied and lowest unoccupied MO of protons of the CH2 groups, especially those directed toward the P atom. The 1H and 31P NMR spectra indicate the formation of hydrides of two types (HRh(BCP)3 and HRh(BCP)4) directly upon the addition of BCP in amounts exceeding that corresponding to the BCP/Rh = 2 ratio to a solution of Rh((acac)(CO)2. The most probable source of the hydride ion is the BCP molecule itself, namely, the bridging CH2 groups. The molecular mechanics simulation showed that in the [Rh(BCP)3]+ complexes the aromatic rings of BCP formed two molecular cavities. These cavities can alternatively open and close, thus providing flexible screening of the catalytic site. This explains the unusual behavior of the Rh complexes with BCP in hydrogenation and hydroformylation.

Quercetin pentaacetate (Qu(OAc)5) was obtained by the acylation of quercetin by method (5) and then reduced with sodium metal in ethanol. The features of the electronic structure of the quercetin pentaacetate reduction product were studied by analyzing the ESR spectra of ketyl resulting from the dissociation of the corresponding pinacolate. Figure 1 shows the ESR spectrum of the sodium ketyl of acetylated quercetin. The calculation of the spin density distribution using the Priroda software allowed us to assign a doublet with а Н = 2 G in the spectrum of quercetin ketyl to the

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

Phosphorous triamides react with aliphatic diols and dibasic phenols: 1,6-hexanediol, 2,2'-(4-hydroxyphenyl)propane, 1,4-hydroquinone, and 4,4'-dihydroxybiphenyl in the temperature range 80-110°C in diethylene glycol dimethyl ether or without a solvent to afford phosphorus-containing regular high-molecular products having an O2P(NR2) moiety in the monomeric unit. The resulting poly(phosphoramidites) are capable of swelling in organic solvents, and they can be used as macroligands in the catalytic hydrogenation of styrene over rhodium(I) complexes.

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.

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 reactivities of cyclophosphite precursors in alkoxo syntheses involving titanium(iv) tetra(n-butoxide) were studied by 31P NMR and IR spectroscopy. 2-Diethylamido-4-methyl-1,3,2-dioxaphosphinane and 4-ethyl-2,6,7-trioxaphosphabicyclo[2.2.2]octane in benzene are inert toward Ti(OBu)4. Gelation is accompanied by hydrolysis 2-diethylamido-4-methyl-1,3,2-dioxaphosphinane to give the corresponding hydrophosphoryl compound, while 4-ethyl-2,6,7-trioxaphosphabicyclo[2.2.2]octane remains intact during gelation.

The hydrolytic activity of ethriol phosphite and triphenyl phosphite in the p-xylene/water two-phase system was studied by the31P NMR method. It was shown that the rate of hydrolysis can be controlled by varying the pH of the aqueous phase. Hydrolysis of triphenyl phosphite is much slower than that of ethriol phosphite in the tested pH range. Coordination of ethriol phosphite with a rhodium carbonyl complex completely suppresses its hydrolysis.

A study has been made of the asymmetric hydrosilylation of acetophenone by diphenylsilane under the influence of rhodium complexes with chiral phosphites. The enantioselective nature of the reaction depends on the phosphite structure, the acetophenone/rhodium and ligana/rhodium ratios, and the temperature. The maximum optical yield (24%) is attainod on the complex [Rh(COD)Cl]2/(S, S)-2-ethoxy-4,5-dicarbisopropoxy-1,3-2-dioxophiospholane.

The influence of the nature of the organophosphorus ligand and the P/Rh molar ratio on the catalytic properties of rhodium carbonyl complexes in hydroformylation of 2-butenes was studied. The difference between phosphine and phosphite ligands during the formation of highly selective catalytic complexes was found. It was supposed that a decrease in the selectivity with respect to 2-methylbutanal is due to the isomerization of olefins under conditions of a decrease in the competitive capability of CO for coordination sites (the high P/Rh ratio, a decrease in the total pressure of the synthesis-gas).

Complete transligation of (AcO)4Rh2 with 4-ethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane was conducted in the solid phase on λ-Al2O3. The reduction of Rh11 to RhI on λ-Al2O3 at 130°C under the actionof the above-mentioned bicyclic phosphite is accompanied by the oxidation of the acetate anion to the acetoxyl radical. The oxidation products were detected by IR and ESR spectroscopy. 2,6-Di-tert-butyl-4-methylphenol was used as a “spin trap” to identify stable secondary radical cations.

It was demonstrated that the catalyst system based on acacRh(CO)2 and polyorgano-siloxanes exhibits high activity and stability in hydroformylation of 1-hexene. The effects of the nature of the oligomer, the ratio of oligomers, and the oligomer: rhodium ratio in the polymer on the synthesis and catalytic properties of the system were studied.

It was shown previously that the larch wood waste can be efficiently processed by passing as aqueous pulp through a disintegrator of cavitator type [1, 2]. By this procedure the wood waste is transformed into a new polymer material called “Cavitated wood.” Besides the cavitated wood, therewith are formed lowmolecular substances: the dihydroquercetin flavonoid, terpenes, terpenoids, etc. [2]. Apparently, the essence of the phenomenon lies in the reorganization of the polymer structure of the original wood raw material, by moving some of its –Ar–C–C–C–X nano-sized blocks. Let us call this lignin nano-isomerization.

s The hydroformylation of olefins in presence catalytic systems on a basis RhCl3*3H2O and a copolymer of styrene with 4-N-pyrrolidinopyridine units in a main chain and acacRh(CO)2 and polymeric organosiloxanes was investigated. These catalytic systems have high stability and activity. The hydroformylation of isobutylene in the presence of such systems proceeds with high speed in conditions, when traditional homogeneous catalysts unactivity. It was showed by ESCA, that complexing of rhodium with pyrrolidinopyridine units of copolymer occurs on atom of nitrogen of pyridine ring. The influence of composition and structure of polymeric supports on creation of active centers of catalysts and their catalytic properties was investigated. The influence of solvents on catalytic properties of polymeric catalysts was studied.

Ligand L I was obtained by the reaction of the diisopropyl ester of (+)-tartaric acid with P(NMe2)2OEt in i:i mole ratio at 120~ Ligand L 2 was obtained by the reaction of the (-)-menthol with di(o,o-di-tert-butyl-p-methyl)phenyl chlorophosphite in absolute benzene at 0~ Both these compounds were characterized by IH, 13C, and 31p NMR and IR spectroscopy and physicochemical indices. Catalysts were obtained in situ from [Rh(COD)CI]z and [RH(CO)2CI]z with L I and L 2. The experiments were carried out in a reactor maintained at constant temperature in an argon atmosphere. The experiment indicated by an asterisk was carried out in CCI 4. The other reactions were carried out without solvent. As shown previously, the reaction temperature and acetophenone:rhodium (AP/Rh) and ligand:rhodium (L*/Rh) ratios affect the enantioselectivity of the catalyst [2]. The results are given in Fig. I. l-Phenylethanol was obtained when the reaction was carried out with the rhodium complexes with L I in optical yield up to 23%. This is the first example of the successful use of phosphite complexes in asymmetric hydrosilylation.

Glycoamidophosphites in the pentose series have been synthesized based on 2,3-O-isopropylidene-β-methyl-D-ribofuranoside, 1,2-O-isopropylidene-α-D-xylofuranose, xylitane and 3,5-O-isopropylidenexylitane. Some of these compounds are used as ligands for the synthesis of the palladium complexes. Consideration is given to the behavior of these complexes as catalysts in the asymmetric hydrogenation of itaconic acid.

1. A phosphine-palladium complex catalyst has been proposed for carbonylation of piperidine to N-for-mylpiperidine in the absence of solvent. The catalyst has high stability. 2. A mechanism for activation of the CO molecule has been proposed, which involves formation of a radical anion in the coordination sphere of the complex and its subsequent reaction with piperidine to form N-for-mylpiperidine.