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A bisdiamidophosphite ligand with stereogenic phosphorus atoms as a part of 1,3,2-diaza-phospholidine rings and a bisoxazoline backbone was synthesized and studied in the Pd-catalyzed asymmetric allylic substitution. The use of this ligand provided up to 93% ee in the alkylation of (E)-1,3-diphenylallyl acetate with dimethyl malonate and up to 77% ee in the amination with pyrrolidine at quantitative conversion of the starting substrate.

O-Phosphorylation of N,N’-(isophthaloyl)di-(S)-tert-leucinol with (5S)-2-chloro-3-phenyl-1,3-diaza-2-phosphabicyclo[3.3.0]octane afforded bidentate phosphite-type ligand. This ligand provided 93% ee in Pd-catalyzed enantioselective allylation of (E)-1,3-diphenylallyl acetate, and 55% ee in alkylation of cinnamyl acetate with ethyl 2-oxocyclohexane-1-carb-oxylate.

A small family of P,P ∗ -bidentate C 1 -symmetric ligands containing 1,3,2-diazaphospholidine rings with stereogenic phosphorus atoms has been prepared. Palladium catalytic systems with these phosphine-diamidophosphites afforded 95% and 63% ees in asymmetric allylic substitution and desymmetrization processes, respectively. The influence of the nature of both the phosphine and diamidophosphite moieties of these compounds on the enantioselectivity is discussed. The ‘mixed-ligand approach’ in Pd-catalyzed asymmetric allylation with participation of some new P ∗ -monodentate diamidophosphites and PPh 3 is also considered.

Novel P -monodentate phosphite-type ligands have been synthesized in one step from BINOL mono-tosylate and BINOL mono-(−)-menthylcarbonate. The use of these ligands provides up to 96% ee in Pd-catalyzed asymmetric allylic substitution of ( E )-1,3-diphenylallyl acetate and up to 99% ee in Rh-catalyzed asymmetric addition of phenylboronic acid to cyclohex-2-enone. The influence of the structural modules such as the nature of phosphorus-containing ring or exocyclic substituent on the enantioselectivity is discussed.

A new series of P * -chiral diamidophosphites with 1,3,2-diazaphospholidine rings, based on (S a )- or (R a )-BINOL and their easily accessible derivatives, has been synthesized for the first time and tested in asymmetric transition metal catalysis. Up to 99% ee was achieved in the rhodium-catalyzed asymmetric hydrogenation of functionalized olefins and in the palladium-catalyzed allylic substitution. The influence of the nature of the donor atoms and denticity on the asymmetric induction is discussed. In addition, the first example of a successful platinum-catalyzed asymmetric allylic amination (up to 86% ee) with participation of organophosphorus ligands is considered.

A series of easily prepared bulky P*-chiral diamidophosphites based on (2R,5S)-3-phenyl-1,3-diaza-2-phosphabicyclo[3.3.0]octane and (2R,5S)-3-(p-bromophenyl)-1,3-diaza-2-phosphabicyclo[3.3.0]octane backbones have been designed and developed. Ligands of this type exhibited high enantioselectivities in Pd-catalysed allylic substitution reactions of (E)-1,3-diphenylallyl acetate with NaSO2pTol (up to 87 % ee), CH2(CO2Me)2 (up to 92 % ee), (C3H7)2NH (up to 93 % ee) and (CH2)4NH (up to 99 % ee). These novel stereoselectors have also been successfully employed in Rh-catalysed asymmetric hydrogenations of dimethyl itaconate (up to 76 % ee), methyl (Z)-2-acetamido-3-phenylacrylate (up to 73 % ee) and methyl 2-acetamidoacrylate (up to 98 % ee). Cu-catalysed conjugate addition of diethylzinc to cyclohexenone leads to a maximum of 70 % ee with quantitative conversion.

A novel readily available P,P-bidentate diamidophosphite ligand with P * -stereocentres is prepared from an inexpensive C2-symmetric 1,4:3,6-dianhydro-D-mannite. By using this efficient ligand, up to 98% ee is achieved in Pd-catalysed asymmetric allylic alkylation, up to 92% ee in Pd-catalysed asymmetric allylic amination and up to 87% ee in Rh-catalysed asymmetric hydrogenation. The influence of the precatalyst, substrate and solvent on the enantioselectivity is discussed. 2008 Elsevier Ltd. All rights reserved.

Several N,P bidentate phosphite-type ligands derived from readily available ferrocene-based iminoalcohols were successfully used in Rh-catalysed hydrogenations and Pd-catalysed allylic substitutions of a variety of substrates. Moderate-to-high catalytic activities under standard conditions were observed, and the enantiomeric excess of the products were up to 97 %. Results obtained under systematic variation of the ligand parameters indicate that the enantioselectivity is largely determined by the nature of the phosphocentre and also by the substituent in the C*HN-fragment. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

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.

Novel diamidophosphite ligand bearing alkylammomium fragment was prepared by a one-step phosphorylation of a quaternised aminoalcohol. The ionic ligand demonstrated high enantioselectivity in the Pd-catalysed allylic substitution of 1,3-diphenylallyl acetate (up to 99% ee).

P-Mono- and P,P-bidentate ligands are examined as catalysts for a range of asymmetric allylic substitutions as well as the desymmetrization process involved in the cyclization of meso bis-urethan (VIII).

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