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Optically active lactams were synthesized from (+)-3-carene and α-pinene enantiomers. Their properties and structures were characterized. A pathway for preparing their trifluoroacetate salts was demonstrated.

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%.

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 reaction of (4S,9S)-4,9-diethyl-2,11-dioxa-5,8-diaza-1λ5-phosphatricyclo[6.3.0.01.5]undecane (1) with [Pt(COD)Cl2] (COD = cycloocta-1,5-diene) at 0 °C gave [(1,2:5,6-η)-1,5-cyclooctadiene][(4S,9S)-4,9-diethyl-5H-5,8-diaza-2,11-dioxa-1λ5-phosphatricyclo[6.3.0.01.5]undecyl-1]chloroplatinum chloride (2). If the reaction was performed in the presence of AgBF4, the corresponding BF4- salt (4) was isolated. Complex 2 was converted to cis-dichloro{(4S,9S)-4,9-diethyl-2,11-dioxa-5,8-diaza-1-phosphabicyclo[6.3.0]undecane-P,N}platinum (3). Variable-temperature 31P NMR studies of complexes 2 and 4 have been carried out in the range from −93 to 50 °C. The structure of compound 4 has been determined by X-ray crystallography. Complex 4 has a slightly distorted trigonal-bipyramidal geometry around the phosphorus, with the platinum fragment in the equatorial position. The P−Nax bond distance is 2.002(5) A. The Pt atom exhibits a nearly square-planar coordination geometry.

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.

Optically active amidophosphite with the peripheral imino group (R)-(Et2N)2POCH2CH(Et)N=CHPh is synthesized through one-stage phosphorylation of the corresponding imino alcohol. Its reaction with [Rh(CO)2Cl]2 (at P : Rh = 1) yields the mononuclear chelate [Rh(CO)(P^N)Cl]. Structures of the compounds are determined by IR, 31P, and 13C NMR spectroscopy, mass spectrometry, and polarimetry.

The coordination of new chiral P,N-hybrid ligands possessing a phosphite-type phosphorus donor centre and azomethine nitrogen to [Rh(CO)2Cl]2 and PdCl2(cod) was examined.

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.