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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.

Chiral 1,3,2-diazaphospholidine with pseudodipeptide substituents was prepared. This asymmetric inducer provided up to 84% ee in the Pd-catalyzed asymmetric allylic alkylation of (E)-1,3-diphenylal...

Diastereomeric P*,P*-bisdiamidophosphite ligands of the 1,3,2-diazaphospholidine series bearing an oxalamide moiety have been synthesized. A possibility of their application in palladium- and rhodium-catalyzed asymmetric transformations was demonstrated. In Pd-catalyzed sulfonylation of (E)-1,3-diphenylallyl acetate with sodium p-toluenesulfinate enantioselectivity of up to 57% ee, in alkylation with dimethyl malonate of up to 77% ee, in amination with pyrrolidine of up to 78% ee, and in alkylation of cinnamyl acetate with ethyl 2-oxocyclohexane-1-carboxylate of up to 52% ee, in Rh-catalyzed hydrogenation of (Z-methyl 2-acetamido-3-phenylacrylate of up to 88% ee was achieved. An effi ciency of diastereomeric chirality inducers was compared.

A practical synthesis of new phosphoramidite, phosphite and diamidophosphite P , N -ligands derived from ( R , R )-tartaric acid was carried out. A study of these chiral inducers showed them to provide up to 93% ee in the Pd-catalyzed asymmetric allylations of ( E )-1,3-diphenylallyl acetate, up to 84% ee in the Pd-catalyzed asymmetric alkylation of cinnamyl acetate with ethyl 2-oxocyclohexane-1-carboxylate and up to 63% ee in the Pd-catalyzed desymmetrization of N , N ′-ditosyl- meso -cyclopent-4-ene-1,3-diol biscarbamate. The effects of the structural modules, such as the nature of the phosphorus-containing ring or exocyclic substituent as well as of the nature of palladium source on the catalytic activity and enantioselectivity were investigated.

New phosphite and amidophosphite inductors of chirality were obtained based on ((4R,5R)-2,2-dimethyl-1,3-dioxolane-4,5-diyl)bis(diphenylmethanol) ((R,R)-TADDOL) containing arylamino groups in the exocyclic substituents. Their use in the palladium-catalyzed enantioselective alkylation of (E)-1,3-diphenylallyl acetate with dimethyl malonate gave the ee value up to 98%.

A small series of P*,P*-bidentate bisdiamidophosphite ligands containing 1,3,2-diazaphospholidine rings have been prepared. The cationic [Pd(allyl)(P*,P*)]BF4 and neutral [Pd(P*,P*)Cl2] palladium(II) complexes were synthesized with one of the new ligands. The use of these ligands provides up to 98% ee in Pd-catalyzed asymmetric allylations of (E)-1,3-diphenylallyl acetate, up to 72% ee in Pd-catalyzed asymmetric alkylation of cinnamyl acetate with ethyl 2-oxocyclohexane-1-carboxylate and up to 94% ee in Pd-catalyzed desymmetrization of N,N'-ditosyl-meso-cyclopent-4-ene-1,3-diol biscarbamate. The influence of the nature of the bridging ligand fragments of the bisdiamidophosphites on asymmetric induction is discussed.

Some novel results obtained at the confluence of organophosphorus and porphyrin chemistry are briefly overviewed. The focus is put on the P*-chiral porphyrin-appended diamidophosphite ligands as we...

Chiral diamidophosphites with 1,3,2-diazaphospholidine cycles were prepared. A study of these chiral inducers showed them to provide up to 97% ee in the Pd-catalyzed allylic alkylation of (E)-1,3-d...

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.

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%.

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.

Synthesis of diastereomeric mono- and bidentate diamidophosphites bearing P*-stereo-centers and phosphabicyclo[3.3.0]octane backbone and their coordination with rhodium(i) and palladium(ii) are considered. Their use in Rh-catalyzed asymmetric allylation allowed one to achieve 87% ee values and the use in Rh-catalyzed asymmetric hydrogenation gave up to 98% ee.

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).

Allylation of dimethyl malonate with 1-(4-chlorophenyl)prop-2-enyl methyl carbonate in the presence of [Pd(All)Cl]2, [Rh(COD)Cl]2, [Ir(COD)Cl]2 (COD is cycloocta-1,5-diene), and a chiral ferrocenyl-containing phosphite ligand based on (R)-BINOL (BINOL is 2,2′-dihydroxy-1,1′-binaphthyl) in CH2Cl2 gave a mixture of linear and branched cross-coupling products, the latter having a moderate optical purity (below 51%). The rhodium-and iridium-catalyzed reactions were very highly regioselective (regiospecific in the case of Ir), giving a branched product. In ionic liquids ([bmim][BF4] and [bdmim][BF4]) (bmim is 1-butyl-3-methylimidazolium and bdmim is 1-butyl-2,3-dimethylimidazolium), the Ir-catalyzed reaction regiospecifically afforded a branched product as a racemate. The same result was obtained with [Ir(COD)Cl]2 as a catalyst; this reaction easily occurred in ionic liquids even without a base.

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

Allylation of dimethyl malonate with 1-(4-chlorophenyl)prop-2-enyl methyl carbonate in the presence of [Pd(All)Cl]2, [Rh(COD)Cl]2, [Ir(COD)Cl]2 (COD is cycloocta-1,5-diene), and a chiral ferrocenyl-containing phosphite ligand based on (R)-BINOL (BINOL is 2,2′-dihydroxy-1,1′-binaphthyl) in CH2Cl2 gave a mixture of linear and branched cross-coupling products, the latter having a moderate optical purity (below 51%). The rhodium-and iridium-catalyzed reactions were very highly regioselective (regiospecific in the case of Ir), giving a branched product. In ionic liquids ([bmim][BF4] and [bdmim][BF4]) (bmim is 1-butyl-3-methylimidazolium and bdmim is 1-butyl-2,3-dimethylimidazolium), the Ir-catalyzed reaction regiospecifically afforded a branched product as a racemate. The same result was obtained with [Ir(COD)Cl]2 as a catalyst; this reaction easily occurred in ionic liquids even without a base.

The first representative of chiral P-monodentate phosphite ligands containing quaternary ammonium substituents and its rhodium complex [Rh(COD)(L)2]BF4 (COD is 1,5-cycloctadiene) were obtained. The use of this ligand in Rh-catalyzed asymmetric hydrogenation of prochiral methyl esters of unsaturated acids allowed one to achieve optical yields up to 99%.