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P*-Mono- and P*,P*-bidentate phosphorodiamidites containing the (S a )-1,1′-binaphthyl core and 1,3,2-diazaphospholidine rings were synthesized. The use of these compounds in the rhodium-catalyzed asymmetric hydrogenation, as well as in the palladium- and platinum-catalyzed asymmetric alkylation and amination, resulted in the formation of the products with ee of up to 99%.

The planar chiral diaryl phosphorimidite ligand containing additional C-stereocenters and neutral and cationic palladium(II) chelates with this ligand, cis-[Pd(η2-P,N)Cl2] and [Pd(Allyl)(η2-P,N)]BF4, were synthesized for the first time. The possibility of using these compounds in asymmetric allylic alkylation of 1,3-diphenylallyl acetate with dimethyl malonate in an optical yield of up to 73% was demonstrated.

Complexation of the chiral P , N -bidentate ferrocene- and cymantrene-based iminoarylphosphites with [Rh(CO) 2 Cl] 2 , [Rh(COD)(THF) 2 ]BF 4 , [Pd(allyl)Cl] 2 , [Pt(allyl)Cl] 4 , [Pd(COD)Cl 2 ] and [Pt(COD)Cl 2 ] was found to give chelate complexes [Rh(CO)(η 2 -P,N)Cl], [Rh(COD)(η 2 -P,N)]BF 4 , [M(allyl)(η 2 -P,N)]BF 4 (M = Pd, Pt) and cis -[M(η 2 -P,N)Cl 2 ] (M = Pd, Pt), correspondingly. With the new P , N -ligands, up to 97% ee was achieved in the asymmetric Pd-catalysed alkylation of 1,3-diphenyl-2-propenyl acetate with dimethyl malonate. In the enantioselective amination of 1,3-diphenyl-2-propenyl acetate with sodium diformylamide, up to 96% enantioselectivity was achieved.

Chiral ferrocene-containing iminoarylphosphite ligands based on 4,4′-dimethoxy-6,6′-di-tert-butyl-biphenyldiol-2,2′ and their chelate complexes with Rh(I) and Pd(II) were synthesized for the first time. They were shown to be perspective reagents in the reactions of asymmetric allyl substitution. The Pd-catalyzed alkylation of 1,3-diphenylallylacetate with dimethyl malonate results in a 87% enantiomer excess (ee), while in sulfonylation of 1,3-diphenylallylacetate with sodium para-toluenesulfinite, this figure amounts to 67%. The results obtained were compared with coordination and catalytic efficiency of a less sterically hindered ferro-cenyliminophosphite based on pyrocatechol. The compositions and structures of new compounds were determined by the 1H, 13C, 31P NMR, IR, mass spectrometry (EI, FAB, and electrospray techniques), and elemental analysis.

The asymmetric synthesis of methyl 2-phenyl-2-(2-phenyl-ortho-carboran-1-yl)pent-4-enoate was carried out by palladium-catalyzed allylation in the presence of amino phosphites of the type (RO)2P—O—CH2—CHR"—NR″2 as chiral ligands.

Published data on the synthesis of rhodium and palladium complexes with optically active P,N-bidentate ligands and their applications in homogeneous asymmetric catalysis are summarised and discussed. The effect of the nature of the P,N-bidentate compounds on the structure of the metal complexes and on enantioselectivity in catalysis is examined. Allylic substitution, cross-coupling, hydroboration and hydrosilylation catalysed by Rh or Pd complexes with optically active P,N-bidentate ligands are considered. The prospects for the development of this field of chemistry are demonstrated. The bibliography includes 186 references.

Monolayer physical adsorption has been considered, taking into consideration the intrinsic volume of the adsorbate molecules. Since an adsorbed molecule occupies not only the site on the surface but also some of the neighboring volume, it creates steric difficulties for the adsorption of other molecules and leads to underestimation of the measured surface area. As a result, this value depends on the size of the adsorbate molecules and the apparent surface dimension can be introduced, even if the surface of narrow pores has no irregularities of atomic scale size. This effect was shown by simulation of adsorption on the surface of Menger sponge. Experimental data for measuring D-values on silica gels with different pore size distributions are in line with this effect.

The overall results of the study of hydrophosphorane compounds as ligands for metal complex synthesis and catalysis are summarised and discussed. The principal types of coordination of hydrophosphoranes, the structure of their metallo-derivatives, and the possible mechanism of the complex formation reaction are examined. The prospects for the employment of hydrophosphoranes in modern coordination design are demonstrated. The bibliography includes 102 references.

Two new chiral binaphthol derivatives are synthesized and used as ligands in transition metal-catalyzed hydrogenation, allylic alkylation and allylic amination reaction.

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.

Published data on the synthesis of rhodium and palladium complexes with optically active P,N-bidentate ligands and their applications in homogeneous asymmetric catalysis are summarised and discussed. The effect of the nature of the P,N-bidentate compounds on the structure of the metal complexes and on enantioselectivity in catalysis is examined. Allylic substitution, cross-coupling, hydroboration and hydrosilylation catalysed by Rh or Pd complexes with optically active P,N-bidentate ligands are considered. The prospects for the development of this field of chemistry are demonstrated. The bibliography includes 186 references.

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.