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Chirality ligands

VAPOL ligand, chiral 25 f. carbenoid center 153 carbenoids 146... [Pg.480]

The phosphetane ring is a useful synthon in the preparation of optically active ligands. Chiral l,2-bis(phosphetano)benzenes 38 are easily prepared from dilithiophenylphosphine 36 by reaction with a cyclic sulfate 37 <00T95>. [Pg.75]

Figure 1.25 Minimum-energy diastereoisomeric monomer free intermediates for butadiene polymerization catalyzed by titanium complexes presenting Cp group as ancillary ligand. Chiralities of coordination of allyl groups (assumed to be si) and back-biting double bonds (si or re) are indicated, in order to easily visualize possible stereoregularity (iso or syndio) of model chains. In fact, like and unlike chiralities would possibly lead to isotactic and syndiotactic enchainments, respectively. Figure 1.25 Minimum-energy diastereoisomeric monomer free intermediates for butadiene polymerization catalyzed by titanium complexes presenting Cp group as ancillary ligand. Chiralities of coordination of allyl groups (assumed to be si) and back-biting double bonds (si or re) are indicated, in order to easily visualize possible stereoregularity (iso or syndio) of model chains. In fact, like and unlike chiralities would possibly lead to isotactic and syndiotactic enchainments, respectively.
In Table 44.1 selected rate constants for the hydrogenation of the dienes COD and NBD for various ligands (chiral and achiral) are summarized. As expected, for all systems investigated, the hydrogenation of NBD was faster than the hydrogenation of COD [13 a, c, 17]. [Pg.1488]

Optically active diols are useful building blocks for the synthesis of chiral diphosphite ligands. Chiral diphosphites based on commercially available optically active 1,2 and 1,4-diols, l,2 5,5-diisopropylidene-D-mannitol, L-a,a,a,a-tetramethyl-l,3-dioxalan-4,5-dimethanol and L-diethyl tartrate, were first used in the asymmetric hydroformylation of styrene [75],... [Pg.167]

Abstract Several bismuth-catalyzed synthetic reactions, which proceed well in aqueous media, are discussed. Due to increasing demand of water as a solvent in organic synthesis, catalysts that can be used in aqueous media are becoming more and more important. Although bismuth Lewis acids are not very stable in water, it has been revealed that they can be stabilized by basic ligands. Chiral amine and related basic ligands combined with bismuth Lewis acids are particularly useful in asymmetric catalysis in aqueous media. On the other hand, bismuth hydroxide is stable and works as an efficient catalyst for carbon-carbon bond-forming reactions in water. [Pg.2]

Chirality Ligand chirality does not, of course, influence the selection of spheres ( ), it may, however, play a role in transport systems. [Pg.15]

In summary, the configuration of the desired product is controlled by the planar-chiral imine and ketimine ligand backbone. The selectivity of the reaction depends on both the chiral center and the communication of the side-chain with the ligand backbone. We tuned the side-chain to increase the enantioselectivity up to 90% ee. In the case of the amino alcohol ligands, chiral cooperativity is also observed. However, the influence of the planar chirality is much lower, whereas central chirality is dominant in this instance. In most cases the enantioselectivity is lower than for the ketimines. [Pg.202]

Symbols R and 5, There are two established and well-u<>ed systems for chirality symbols and these differ in fundamental ways. The first, the convention for chiral carbon atoms is equally appropriate to metal complexes and is most often used in conjunction with ligand chirality. However, it can be applied to metal centers Hnd has been useful for pseudotetrahedral organometallic complexes when, for example, cyclopcnhidienyl ligands are treated as if they were monodentate ligands of high priority. [Pg.531]

RLi (R = 1° alkyl, aryl, vinylic), chiral ligand (chiral)... [Pg.847]

C2-Symmetric Ligands Chiral Semicorrin/Bis-oxazoline Cu Catalysts... [Pg.197]

To a first approximation, the chiral discrimination should be independent of the nucleophile. The palladium-catalyzed desymmetrization protocol utilizing a heterocyclic nucleophile provides enantio- and diastereoselective entries to diverse carbo-nucleosides. As shown in Scheme 8E.9, introduction of purine bases rather than the hydroxymethyl synthon also affords high enantioselectivities [61]. A variety of natural and unnatural nucleosides can be flexibly prepared because the simple change of ligand chirality or, alternatively, switching the alkylation sequence leads to opposite enantiomers. The palladium-catalyzed approach sharply contrasts with the chiral-pool method, whose enantiodivergency is limited by the availability of the starting material. [Pg.606]


See other pages where Chirality ligands is mentioned: [Pg.225]    [Pg.480]    [Pg.480]    [Pg.480]    [Pg.23]    [Pg.8]    [Pg.105]    [Pg.271]    [Pg.285]    [Pg.436]    [Pg.54]    [Pg.103]    [Pg.225]    [Pg.739]    [Pg.740]    [Pg.225]    [Pg.186]    [Pg.243]    [Pg.575]    [Pg.240]    [Pg.895]    [Pg.1544]    [Pg.857]    [Pg.175]    [Pg.601]    [Pg.782]    [Pg.217]    [Pg.39]    [Pg.336]    [Pg.360]   
See also in sourсe #XX -- [ Pg.24 ]




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Addition reactions chiral ligands

Allylic chiral ligands

Amino acids as chiral ligands

Applications of Chiral Phosphorous Ligands in Rhodium-Catalyzed Asymmetric Hydrogenation

As Chiral Auxiliaries and Ligands

Asymmetric ligands allylic derivatives, substitution reactions, chiral

Asymmetric transfer hydrogenation chiral amino alcohol ligand

Atropisomerically chiral ligand, BINAP

Axial chiral compounds ligands

Based Chiral Ligands in C-F Bond Forming Reactions

Bidentate ligand, chiral

Butenyl ligands chirality

C2 Symmetric chiral diphosphite ligands

Catalytic Reactions with Chiral Ligands

Central chirality bidentate ligands

Central chirality monodentate ligands

Chiral Auxiliaries and Ligands in Asymmetric Synthesis

Chiral Bisphosphane Ligands through Modifications of DuPhos and BPE

Chiral Ferrocene-based Bisphosphane Ligands

Chiral Ligands for Special Substrates

Chiral Monophosphorus Ligands

Chiral N, P Ligands

Chiral Phosphorus Ligands

Chiral Phosphorus Ligands for Stereoselective Hydroformylation

Chiral Schiff-base salen ligands

Chiral Separation by Ligand Exchange

Chiral amidinate ligands

Chiral amidophosphine ligands

Chiral aminophosphine chelate ligands

Chiral aminophosphine ligands

Chiral aminophosphine-phosphinite ligands

Chiral asymmetric ligands

Chiral atropisomeric biaryl bisphosphine ligands

Chiral bidentate phosphorus ligands

Chiral bidentate phosphorus ligands BINAP

Chiral binaphtholate ligands

Chiral binaphthyl ligand

Chiral biphosphine ligands

Chiral bisoxazoline ligand

Chiral bisphosphane ligands

Chiral bridging ligands

Chiral catalysts ligands

Chiral chelating ligands

Chiral complexes, drugs, ligands

Chiral compounds monodentate ligands

Chiral diaminophenolate ligands

Chiral diaza ligand

Chiral diene ligand

Chiral ferrocene based phosphine phosphoramidite ligands

Chiral ferrocene diphosphine ligand

Chiral ferrocenyldiphosphine ligand

Chiral formamide ligand

Chiral hydrophobic ligands

Chiral ligand acceleration

Chiral ligand asymmetrical synthesis

Chiral ligand elements

Chiral ligand exchange chromatograph

Chiral ligand exchange chromatography CLEC)

Chiral ligand phosphorus-based

Chiral ligand, -sparteine

Chiral ligand, chemical shifts

Chiral ligand-exchange

Chiral ligand-exchange CLEC)

Chiral ligand-exchange chromatography

Chiral ligand-exchange separations

Chiral ligand-exchange-type

Chiral ligand-exchangers

Chiral ligands

Chiral ligands

Chiral ligands 1.2] -Wittig rearrangement

Chiral ligands BINAP

Chiral ligands BINOL

Chiral ligands Fujiwara-Moritani reaction

Chiral ligands Lewis acid catalysts

Chiral ligands Subject

Chiral ligands TADDOL

Chiral ligands TADDOL catalysis with

Chiral ligands TADDOL-derived

Chiral ligands addition with

Chiral ligands alkyl halide carbonylation

Chiral ligands alkynylation

Chiral ligands allylic derivatives, substitution reactions

Chiral ligands asymmetric Heck reaction

Chiral ligands asymmetric amplification

Chiral ligands asymmetric hydrogenation

Chiral ligands bidentate phosphine

Chiral ligands carbene

Chiral ligands chlorohydrin synthesis

Chiral ligands design

Chiral ligands dioxaborolane

Chiral ligands disulfonamide

Chiral ligands enantioselectivity

Chiral ligands ferrocenes

Chiral ligands for asymmetric hydrosilylation

Chiral ligands future developments

Chiral ligands multidentate

Chiral ligands nitrogen-containing

Chiral ligands phosphoramidite

Chiral ligands salans

Chiral ligands sulfinyl groups

Chiral ligands sulfur-palladium complexes

Chiral ligands terpenes

Chiral ligands, Betti reaction

Chiral ligands, Sharpless asymmetric

Chiral ligands, Sharpless asymmetric hydroxylation reactions

Chiral ligands, bifunctional

Chiral ligands, introduced into polymers

Chiral ligands, preparation

Chiral ligands, uses

Chiral macrocyclic ligand

Chiral metal complexes ligand transformation

Chiral monodentate phosphite ligands

Chiral monodentate phosphoramidite ligands

Chiral monodentate phosphorus ligands

Chiral monophosphoramidite ligand

Chiral nonracemic ligands

Chiral norbomadiene ligand

Chiral oxazoline ligands

Chiral phases ligand exchange

Chiral phosphane ligands

Chiral phosphinamine ligands

Chiral phosphine ligand

Chiral phosphine-phosphite ligands containing a stereocenter in the backbone

Chiral phosphorous ligands

Chiral poly-NHC ligands

Chiral salen ligands

Chiral salicylaldimine ligands

Chiral spiro ligands

Chiral tertiary amine ligand

Chiral thioether ligands

Chiral tosylated diamine ligands

Chiral water soluble ligands

Chirality transfer bipyridine ligands

Chirality transfer ligands

Chirality transfer phosphite ligands

Chirality transfer via resolved bridging ligands

Chirality-Directed Self-Assembly An Enabling Strategy for Ligand Scaffold Optimization

Cinchona Alkaloids as Chiral Ligands in Asymmetric Oxidations

Cinchona chiral ligands

Coordinated ligands, chirality polymerization

Coordinated ligands, chirality polymerization mechanisms

Covalent chiral ligand/catalyst

DIOP ligands, chiral palladium complexes

Davankov ligand exchange chiral

Diamine ligands, chiral

Dinitrogen ligands, chiral

Diphosphine ligand, chiral

Duphos chiral ligand

Effect of chiral ligand

Enantioselective Synthesis or Resolution of Chiral Ligands

Enantioselective addition chiral ligands

Ferrocene derivatives chiral ligands

Ferrocene-based chiral ligands

Ferrocenyloxazolines, chiral ligands

General Features of Chiral Ligands and Complexes

Hayashi-Miyaura reaction chiral ligands

Helical chiral phosphorus ligand

Helically chiral ligands

Hexadentate chiral ligand

High-Throughput Screening of Chiral Ligands and Activators

High-throughput screening chiral ligands

Hydrogenation, catalytic, alkene chiral ligands

INFLUENCE OF CHIRAL LIGANDS

Lewis acids chiral acid-ligand system

Ligand chiral sulfoxide

Ligand chiral tertiary phosphine

Ligand containing chiral phosphine

Ligand exchange chiral selectors

Ligand structures chirality

Ligand, Chiral bipyridine

Ligand-exchange chiral stationary phases

Ligand-exchange chromatography chiral separations

Ligands chiral Schiff base

Ligands chiral amino alcohol-based

Ligands chiral binaphthyl ligand

Ligands chiral bisphospholane

Ligands chiral chelate

Ligands chiral geometry

Ligands chiral phosphines, influence

Ligands external chiral

Ligands planar chiral

Ligands, chiral reaction

Ligands, chiral, immobilization

Ligands, chirally selective

Lithium aluminum hydride chiral ligands

Macrocyclic ligands chirality

Metal Complexes of Chiral Ligands

Metallomesogens Where the Metal and Ligands Generate Helical Chirality

Monodentate chiral ligands

Monodentate chiral ligands phosphites

Monodentate chiral ligands phosphonites

Monodentate chiral ligands phosphoramidites

New Chiral Ligands Based on Substituted Heterometallocenes

New chiral benzothiazine ligand for catalysis and molecular recognition

Nickel catalysts chiral oxazoline ligands

Nontransferable ligands chiral

Organolithium reagents chiral ligands

Organolithium reagents, external chiral ligands

Other Water-soluble Chiral Ligands

Oxazoline-based chiral ligands

P-chiral Bisphosphane Ligands

Paracyclophanes as Chiral Ligands

Phosphaferrocene ligands, planar chirality

Phosphinooxazolines ligands , chiral

Planar Chiral Ferrocene ligands

Planar chiral compounds bidentate ligands

Poly-NHCs ligands chiral

Polydentate ligands chirality

Protic chiral ligands

Pyrrolidine 2- -: chiral ligand

Pyrrolidine, chiral copper ligand

Reaction of Other Organometals Using External Chiral Ligands

Reaction of homoorganocoppers using external chiral ligands

Reaction of organozinc using external chiral ligands

Reactivity chiral aminophosphine ligands

Rhodium catalyzed asymmetric chiral 1,4 diphosphine ligands

Rhodium different chiral ligands

Ruthenium complexes chiral chelating ligands

Ruthenium compounds with chiral ligand

Segphos chiral ligand

Stereoinduction from chiral ligands on the enolate metal

Sulfoxide complexes of chiral ligands

Tethered chiral ligands

Tetradentate chiral ligand

Titanium complexe chiral ligand

Tridentate chiral ligands

Tridentate chiral ligands, enantioselective

Zinc catalysts supported by chiral diaminophenolate ligands

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