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A series of diamidophosphite ligands of various structures and denticities were synthesized from (11S,12S)-bis(hydroxymethyl)-9,10-dihydro-9,10-ethanoanthracene as a "roof shaped" 1,4-diol. On the basis of these ligands, we obtained three types of Pd(II) allylic complexes: a P,P-chelate, a P,S-bridged head-to-tail dinuclear complex, and complexes each containing a pair of P-monodentately coordinated P-, P,N- or P,S-ligands. The structures of the ligands and their complexes were determined using 2D NMR spectroscopy. Four diamidophosphites were also characterized via their X-ray structural data. This kind of stereoselector exhibited up to 98% ee in the Pd-mediated allylic substitution of (E)-1,3-diphenylallyl acetate with C- and N-nucleophiles. In the Pd-catalyzed allylic alkylation of cinnamyl acetate with various C-nucleophiles, ee values of up to 90% were obtained. In addition, up to 71% ee was achieved in the Pd-catalyzed asymmetric amination of 2-(diethoxyphosphoryl)-1-phenylallyl acetate with aniline, which is a pioneering example of diamidophosphite-type ligand involvement in this challenging reaction. The effects of the diamidophosphite moiety and the denticity of the ligands on the catalytic activity and enantioselectivity were investigated. [ABSTRACT FROM AUTHOR]

Two groups of modular chiral diamidophosphite ligands were easily synthesised from accessible N-Boc-amino alcohols and pseudodipeptides. The reaction of these compounds with [Pd(allyl)Cl]2 in the presence of AgBF4 yielded complexes [Pd(allyl)(L)2]BF4. In addition, metallochelates [Pd(allyl)(L)]BF4 with (S)-methioninol-based P,S-bidentate ligands were prepared. The structures of the novel ligands and complexes were elucidated by means of 2D-NMR and were confirmed by single-crystal X-ray diffraction, as well as by DFT calculations. Asymmetric inducers of this type exhibited high enantioselectivities in the Pd-mediated allylic substitution of (E)-1,3-diphenylallyl ethyl carbonate with CH2(CO2Me)2 (up to 98% ee) and (CH2)4NH (up to 92% ee). Ee values of up to 86% and 73% were obtained in the Pd-catalyzed allylic alkylation of cinnamyl acetate with ethyl 2-oxocyclohexane-1-carboxylate and ethyl 2-oxocyclopentane-1-carboxylate, respectively. The effects of the structural modules, such as the nature of the phosphorus-containing ring or exocyclic substituent, on the catalytic activity and enantioselectivity were investigated. [ABSTRACT FROM AUTHOR]

An efficient and convenient one-pot procedure for the stereoselective catalytic synthesis of ring-substituted [amino(phenyl)methyl]phosphonates has been developed. The enantioselective hydrogenation of easily available diisopropyl ( Z)-[aryl(phenylhydrazono)methyl]phosphonates using palladium(II) acetate as a precatalyst, ( R)-2,2′-bis(diphenylphosphino)-5,5′-dichloro-6,6′-dimethoxy-1,1′-biphenyl [( R)-Cl-MeO-BIPHEP] as a ligand, and (1 S)-(+)-10-camphorsulfonic acid as an activator in a mixture of 2,2,2-trifluoroethanol and methylene chloride at ambient temperature results in the formation of corresponding [aryl(2-phenylhydrazino)methyl]phosphonates. The subsequent cleavage of the N−N bond has been accomplished with molecular hydrogen after the addition of palladium on carbon and methanol into crude reaction mixture to afford the optically active [amino(aryl)methyl]phosphonates. The method is operationally simple and provides an appreciable enantioselectivity up to 98 % ee. [ABSTRACT FROM AUTHOR]

A series of 2-aryl-substituted 1-aminocyclopropylphosphonates containing an additional remote phosphonate group have been synthesized starting from readily accessible dimethyl (1R*,2R*)-2-(4-bromophenyl)-1-formamidocyclopropylphosphonate using cross-coupling methodology. Different types of palladium-catalyzed reactions for carbon-carbon and carbon-phosphorus bond formation were realized. In each case the optimum conditions were found to obtain the desired products in high yield in both small- and large-scale experiments. [ABSTRACT FROM AUTHOR]

The enantioselective synthesis of ring-substituted [ N-(hydroxy)amino](phenyl)methylphosphonic esters via asymmetric hydrogenation of the corresponding N-hydroxy- α-imino phosphonates with up to 90% ee was developed using catalytic amounts of palladium(II) acetate and ( R)-BINAP in 2,2,2-trifluoroethanol with a Brønsted acid as an activator. [ABSTRACT FROM AUTHOR]

This is the first catalytic, most straightforward, and atom-economical approach to enantioenriched N-hydroxy-α-amino-phosphonates (II). [ABSTRACT FROM AUTHOR]

The potassium salt of phosphoglycine Schiff base (III) is a suitable nucleophile for the direct preparation of the phosphonic analogues of α-C-perfluoro(het)aryl-substituted glycine esters via SNAr reaction with perfluoro(het)arenes (IV), providing title compounds (V) under mild conditions in satisfactory yields and high regioselectivity. [ABSTRACT FROM AUTHOR]

A series of easy-to-prepare and modular chiral P , S -bidentate phosphoramidites were synthesized. With respect to Pd(II), these ligands showed the ability to form stable P , S -chelate allylic complexes. The structures of the ligands and their complexes were confirmed by 2D NMR spectroscopy and single-crystal X-ray diffraction. These chiral inducers provided up to 99% ee in the Pd-catalyzed asymmetric allylic substitution of ( E )-1,3-diphenylallyl acetate with C- and N-nucleophiles and up to 94% ee in the Pd-mediated allylic alkylation of cinnamyl esters with β-ketoesters and 2,5-dimethylpyrrole. Furthermore, up to 92% ee with quantitative conversion and chemo- and regioselectivity was achieved in the rare reaction between 2-(diethoxyphosphoryl)-1-phenylallyl acetate and aniline. The effects of the structural parameters, reaction conditions and ligand-to-metal ratio on the catalytic results are discussed. It was shown that the ligands surpass their analogues with different denticity.