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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.

Previously unknown chiral P,N-bidentate N-pyrrolylphosphines and their chelate complexes [Rh(η2-P,N)(CO)Cl] and [Pd(Allyl)(η2-P,N)]BF4 were synthesized by phosphorylation of (E,1R,2R,3R,5S)-2-[(2,6,6-trimethylbicyclo[3.1.1]heptyl-3-)iminomethyl]-1H-pyrrole. The composition and structures of the novel compounds were determined by the 1H, 13C, and 31P NMR, IR, mass spectrometry (electrospray), and elemental analysis methods. N-pyrrolylphosphines were found to have unusual electronic properties, being simultaneously more strong π-acids and σ-bases as compared to phosphites.

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.

Phosphorylation of (S)-prolinol with P(NEt2)3was used to synthesize aminophosphite (2R,5S)- $${\text{HCH}}_{\text{2}} {\text{OPNEt}}_{\text{2}} $$ , which was reacted with the corresponding amino alcohols to afford (2S,5R)- $${\text{CH}}_{\text{2}} \left( {{\text{CH}}_{\text{2}} } \right)_2 {\text{NCHCH}}_{\text{2}} {\text{OPO}}\left( {{\text{CH}}_{\text{2}} } \right)_2 {\text{NMe}}_{\text{2}} $$ (Va) and (2S,5R)- $${\text{CH}}_{\text{2}} \left( {{\text{CH}}_{\text{2}} } \right)_2 {\text{NCHCH}}_{\text{2}} {\text{OPO}}\left( {{\text{CH}}_{\text{2}} } \right)_2 {\text{N}}\left( {{\text{CH}}_{\text{2}} } \right)_{\text{4}} {\text{CH}}_{\text{2}} $$ (Vb). Reaction of Vawith [Rh(CO)2Cl]2(P/Rh = 1) yields the mononuclear chelate [Rh(CO)(P^N)Cl] (VIIa), while the analogous reaction with Vbresults in a mixture of products with cis- and trans-orientation of the coordinated phosphorus and nitrogen atoms. Spectral characteristics of the products of coordination of ligands Vaand Vbwere compared with those for the binuclear reference complex [Rh(CO)(L)Cl]2(VIII), where L is P-monodentate ligand (2S,5R)- $${\text{CH}}_{\text{2}} \left( {{\text{CH}}_{\text{2}} } \right)_2 {\text{NCHCH}}_{\text{2}} {\text{OPOEt}}_{\text{2}} $$ (VI). The ligands and complexes were studied by IR, NMR, 31P and 13C spectroscopy, mass spectrometry, and elemental analysis methods. X-ray diffraction analysis of crystals VIIIwas performed.

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.