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Complexes chiral

It is also possible to separate the optical isomers through chromatography on a chiral cation-exchange resin (such as SP-Sephadex C-25 resin) by using a chiral eluate such as a d-tartrate solution. Differential binding to the resin, which is itself chiral, means the complex separates on a sufficiently long column into two bands comprising the two optical forms of the complex. [Pg.189]

Chirality is often met with polydentate ligands at a number of different centres in the complex, and separation of all optical isomers is either impractical or, in effect, impossible. In many cases, working with a racemate has no significant influence on the chemistry, and optical resolution of complexes is attempted on only very limited occasions, such as where researchers wish to record the chiroptical properties, or where a chiral complex is required to assist in achieving a chiral reaction, such as use of a chiral complex as a catalyst in synthesis of organic molecules where a particular optical isomer is sought (exemplified in Chapter 9). [Pg.189]


Another possibility for asymmetric reduction is the use of chiral complex hydrides derived from LiAlH. and chiral alcohols, e.g. N-methylephedrine (I. Jacquet, 1974), or 1,4-bis(dimethylamino)butanediol (D. Seebach, 1974). But stereoselectivities are mostly below 50%. At the present time attempts to form chiral alcohols from ketones are less successful than the asymmetric reduction of C = C double bonds via hydroboration or hydrogenation with Wilkinson type catalysts (G. Zweifel, 1963 H.B. Kagan, 1978 see p. 102f.). [Pg.107]

In the classical set-up of bulk liquid membranes, the membrane phase is a well-mixed bulk phase instead of an immobilized phase within a pore or film. The principle comprises enantioselective extraction from the feed phase to the carrier phase, and subsequently the carrier releases the enantiomer into the receiving phase. As formation and dissociation of the chiral complex occur at different locations, suitable conditions for absorption and desorption can be established. In order to allow for effective mass transport between the different liquid phases involved, hollow fiber... [Pg.130]

In a rather different approach optically active chromium complexes of 2,3-dihydro-1 H-in-denone are used as chiral enolate precursors. These chiral complexes react with 3-buten-2-one in benzene using l,5-diazabicyclo[4.3.0]non-5-ene as the base. The diastereomeric ratio of the product is the same irrespectively of whether the exo- or the Noisomer of the chromium... [Pg.971]

An asymmetric version of this reaction was achieved by the use of complexes derived from chiral imidazolidinones. For example, the reaction of Danishefsky s diene with these chiral complexes occurs with both high exo endo selectivity and high facial selectivity at the dienophile [103] (Scheme 56). [Pg.96]

A chiral complex is one that is not identical to its mirror image. Thus, all optical isomers are chiral. The cis isomers of [CoCl2(en)2 + are chiral, and a chiral complex and its mirror image form a pair of enantiomers. The trans isomer is superimposable on its mirror image complexes with this property are called achiral. Enantiomers differ in one physical property chiral molecules display... [Pg.796]

Alkyl halides or alkyl sulfates, treated with the salts of sulfinic acids, give sulfones. A palladium catalyzed reaction with a chiral complexing agent led to sulfones with modest asymmetric induction. Alkyl sulfinates (R SO—OR) may be side products. Sulfonic acids themselves can be used, if DBU (p. 1337) is... [Pg.498]

The 4-thiazolidinyl phosphonates 143 (Scheme 44) are known for their therapeutical properties, in particular as anti-inflammatory agents [5,89]. Their asymmetric synthesis by hydrophosphonylation of 3-thiazolines has been described using various chiral auxiliaries chiral phosphites such as (2S,4i )-2H-2-oxo-5,5-dimethyl-4-phenyl-l,3,2-dioxaphosphorinane (de = 2-8%) [90] or BINOL-phos-phite (de = 65-90%) [91] and also chiral catalyst such as titanium or lanthanide chiral complexes (ee = 29-98%) [92]. Hydrophosphonylation of C2-chiral3-thi-azolines has also been performed (de = 32-38%) [93]. [Pg.191]

Probably the first non-covalent immobilization of a chiral complex with diazaligands was the adsorption of a rhodium-diphenylethylenediamine complex on different supports [71]. These solids were used for the hydride-transfer reduction of prochiral ketones (Scheme 2) in a continuous flow reactor. The inorganic support plays a crucial role. The chiral complex was easily... [Pg.183]

M-heterocyclic carbenes are neutral compounds with a divalent carbon atom located between the two nitrogens. The four types of stable diaminocarbenes used for the synthesis of chiral complexes are listed below (Fig. 2) ... [Pg.192]

Mono or bis-carbene complexes are possible depending on the carbene/ metal precursor ratio and the steric bulk of the carbene. Most of the metal precursors and bases used for the synthesis of chiral complexes are presented below Metal precursors ... [Pg.196]

Using these procedures, many chiral diaminocarbene-transition metal complexes have been synthesized but only a few of them have been used for asymmetric catalysis. The chiral complexes which were isolated but did not receive any application in asymmetric catalysis, are presented at the end of the chapter. [Pg.197]

AT-heterocyclic carbene complexes of Pd(II) or Pd(0) were extensively used in various reactions and several groups have reported syntheses of chiral complexes [5]. However, only a few examples of asymmetric catalysis are... [Pg.205]

Platinum-thiourea complexes have been extensively studied because of their biological activity [54], but few have been used in catalysis. Neutral thioureas are able to coordinate to metal centres through their sulfur atom (Scheme 9) [55,56] monomeric (I) and oligomeric (II) species are known for Rh [57], and an X-ray structure has also been determined for the chiral complex III [58]. In many complexes hydrogen bonding has been observed... [Pg.239]

Mejorado investigated the asymmetric addition of various organometallic nucleophiles using method A, but the reaction could not be catalyzed. The intermediates proved to be far too reactive. However, he established that the addition of a stoichiometric amount of a preformed chiral complex [an admixture of Taddol (r/om-a, -(dimethyl-1,3-dioxolane-4,5-diyl)bis(diphenyl methanol)) and EtMgBr] to 5 affords some enantiomeric excess in the resulting phenol product 6 (Fig. 4.12).13... [Pg.95]

Examples of some Cl chiral complexes with octahedral coordination... [Pg.84]

An enantioselective variant of the diene cydization reaction has been developed by application of chiral zirconocene derivatives, such as Brintzinger s catalyst (12) [10]. Mori and co-workers demonstrated that substituted dial-lylbenzylamine 25 could be cyclized to pyrrolidines 26 and 27 in a 2 1 ratio using chiral complex 12 in up to 79% yield with up to 95% ee (Eq. 4) [ 17,18]. This reaction was similarly applied to 2-substituted 1,6-dienes, which provided the analogous cyclopentane derivatives in up to 99% ee with similar diastereoselectivities [19]. When cyclic, internal olefins were used, spirocyclic compounds were isolated. The enantioselection in these reactions is thought to derive from either the ate or the transmetallation step. The stereoselectivity of this reaction has been extended to the selective reaction of enantiotopic olefin compounds to form bicyclic products such as 28, in 24% yield and 59% ee after deprotection (Eq. 5) [20]. [Pg.223]

The X-ray structure of [cp Ir(CNR)Cl2], CNR = l,3,4,6-tetra-0-acetyl-2-deoxy-2-isocyano-Q,, 3-D-glucosc, has been determined.428 The synthesis of chiral complexes of Ir111 with Q-amino acid anions, L-L, of general formula [cp Ir(Cl)(L-L )] (252), and their NMR spectroscopic characterization, have been detailed. The X-ray structures of (252), L-L = L-proline and [cp Ir(Cl)(L-His-OH)]Cl, His = histidine, are described.429 C-allylglycinate binds in a terdentate manner in (253), which has been characterized by X-ray diffraction studies.430 C-vinylglycinate forms complex (254). [Pg.194]


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1,3-Dicarbonyl compounds chiral metal complexes

A-chiral Lewis acid complexes

Acetonitriles, chiral palladium complexes

Alkenes chiral complexes

Alkenes rhodium chiral complexes

Alkyllithiums chiral lithium amide mixed complexes

Aluminium chiral salenAl complexes

Aluminum enolates from chiral acyl-iron complexes

And chirality complexation

Ansa-metallocene complexes chiral

Application of Chiral Pincer Complexes

Asymmetric Aziridination of Olefins with Chiral Nitridomanganese Complexes

Asymmetric Catalysis by Chiral Indium Complexes

Asymmetric catalysis chiral lanthanoid complexes

Asymmetric conjugate addition chiral nickel complex

Asymmetric epoxidation chiral metal complex catalysis

Asymmetric hydrogenations over chiral metal complexes immobilized in SILCA

Asymmetric oxidation with chiral titanium complexe

Benzene, 1 - complexes chirality

Borane complexes chiral boron

Catalysis by Metal Complexes and Chiral Phosphoric Acids

Catalysis chiral metal complexes

Catalyst research, chiral molecular complexes

Catalytic hydrogenation with chiral transition metal complexes

Catalytic oxidative coupling of 7-Alkoxy-l-naphthols by chiral vanadium complexes

Chelate complexes chiral

Chiral Co-salen complex

Chiral Complexes of the and Types

Chiral Cu complex

Chiral Half-Sandwich Arene Complexes

Chiral Lewis Acid Complexes

Chiral Ln(III) Complexes to Probe Biologically Relevant Systems

Chiral Metallo-macrocycles with Organometallic Half-sandwich Complexes

Chiral Metallocene Complexes

Chiral Mn complex

Chiral NHCP complexes

Chiral Ni complexes

Chiral Pd complexes

Chiral Rh-complex

Chiral Ru complexes

Chiral Separation by Inclusion Complexes

Chiral Zr-complexes

Chiral actinide complexes

Chiral acyl iron complexes

Chiral aluminium complex

Chiral biphosphines, rhodium complexes

Chiral carbene complexes

Chiral chromium carbonyl complex

Chiral cobalt complex

Chiral complexes 2,2]-paracyclophane

Chiral complexes containing

Chiral complexes examples

Chiral complexes nomenclature

Chiral complexes planar

Chiral complexes, assigning

Chiral complexes, catalysis

Chiral complexes, determination

Chiral complexes, drugs, ligands

Chiral complexes, with hydrides

Chiral complexing agent

Chiral compounds complexes

Chiral copper Schiff base complexes

Chiral copper complexes

Chiral copper complexes structure

Chiral dimeric complexes

Chiral dinuclear metal complex

Chiral discrimination complex ions

Chiral gold complexes

Chiral homogeneous metal complexe

Chiral indium complexe

Chiral indium salen complexes

Chiral ion-dipole complexes

Chiral iridium complex catalysts

Chiral lanthanocene complex

Chiral lanthanoid complexes, asymmetric

Chiral ligands sulfur-palladium complexes

Chiral macrocycles complex formation

Chiral macrocycles host-guest inclusion complexes

Chiral metal complexes

Chiral metal complexes Claisen rearrangement

Chiral metal complexes absolute configuration

Chiral metal complexes aldol reactions

Chiral metal complexes alkylation

Chiral metal complexes asymmetric synthesis

Chiral metal complexes chiroptical properties

Chiral metal complexes configurational stability

Chiral metal complexes conjugate addition

Chiral metal complexes cycloaddition

Chiral metal complexes electrophilic allylation

Chiral metal complexes functional group transformation

Chiral metal complexes hetero-Diels-Alder reaction

Chiral metal complexes hydrogenation

Chiral metal complexes hydrosilylation

Chiral metal complexes hydrovinylation

Chiral metal complexes isomerization

Chiral metal complexes ligand transformation

Chiral metal complexes metals

Chiral metal complexes notation

Chiral metal complexes optical induction

Chiral metal complexes optical purity

Chiral metal complexes optical resolution

Chiral metal complexes organic halides

Chiral metal complexes oxidation

Chiral metal complexes pericyclic reaction

Chiral metal complexes radical reactions

Chiral metal complexes rhenium

Chiral metal complexes separation

Chiral metal complexes, allylic alcohol

Chiral metal-complex catalysts

Chiral nitrido complexes

Chiral nitridomanganese complex

Chiral nonracemic metal complexes

Chiral organo-transition-metal complexes

Chiral palladium complexes in situ generation

Chiral phosphines phosphorus-palladium complexes

Chiral platinum complex

Chiral polymetallic complex

Chiral recognition complexes

Chiral recognition diastereomeric complexes

Chiral recognition molecule complex

Chiral recognition octahedral metal complexes

Chiral rhodium carboxylate complexes

Chiral ruthenabicyclic complex

Chiral ruthenium complexes

Chiral salen complexes

Chiral salen-manganese complex

Chiral selector complex

Chiral silyl-transition-metal complexes

Chiral stationary phases metal complexes

Chiral titanium complex, oxidation

Chiral titanium complexes asymmetric oxidation with

Chiral titanium complexes oxidation of sulfides with

Chiral titanium hydride complexes

Chiral-Metal-Complex-Catalyzed Aliphatic Claisen Rearrangement

Chiral-at-metal complexes

Chirality Transfer in Polynuclear Complexes Enantioselective Synthesis

Chirality amino acid complexes

Chirality chiral titanium complexes

Chirality complexes

Chirality complexes

Chirality in Organometallic Anticancer Complexes

Chirality lanthanide complexes with achiral

Chirality lanthanide complexes with chiral

Chirality multiplication metal complexes

Chirality polynuclear transition metal complexes

Chirality/Chiral complexes

Chirality/Chiral complexes

Chirally selective complexing agent

Chromium chiral arene complexes

Chromium complexes chiral

Cobalt complexes chiral cyclopentadienyls

Complexes chiral lanthanide

Complexes chiral transition metal

Complexes chirally resolved

Coordination chemistry chiral metal complexes

Coordination complexes, chirality induction

Copper complexes chiral recognition

Copper complexes chiral surfaces

Cyclometallated chiral palladium complexes

DIOP ligands, chiral palladium complexes

Divalent chiral palladium complexes

Enantioselective Michael addition chiral metal complexes

Enantioselective Mukaiyama Aldol Reaction Promoted by Chiral Lanthanide Complexes

Enantioselective oxidative coupling of 2-Naphthols catalyzed by a novel chiral vanadium complex

Enantioselective reactions chiral complexing agent

Enantioselective synthesis chiral metal complexes

Encapsulated Chiral Complexes

Enones chiral metal complexes

Ethers, Taddol, Nobin and Metal(salen) Complexes as Chiral Phase-Transfer Catalysts for Asymmetric Synthesis

General Features of Chiral Ligands and Complexes

Half-Sandwich Complexes with Chiral Metal Centers

Helical chirality octahedral metal complexes

Helical chirality palladium complexes

Host, chiral, inclusion complexation

Host-guest inclusion complexes chiral crown ether hosts

Hydride, chiral complexes

Hydroboration chiral metal complexes

Hydrocyanation chiral metal complexes

Hydroformylation chiral metal complexes

Hydrogenation chiral complexes

Immobilized chiral metal complexe

Immobilized chiral metal complexes

Inclusion complexation chiral recognition mechanisms

Indium complex chiral

Industrial immobilized chiral metal complexe

Ionic complexes, chiral interactions

Iridium catalysts alkenes, chiral complexes

Iridium complexes chirality transfer

Iridium complexes, chiral

Iron complexes chiral

Iron complexes chiral recognition

Iron complexes, cationic chiral

Iron complexes, dienyladdition of chiral nucleophiles

Iron complexes, dienyladdition of chiral nucleophiles enantiomerically enriched

Iron complexes, dienyladdition of chiral nucleophiles nucleophilic additions

Iron complexes, dienyladdition of chiral nucleophiles resolution

Iron complexes, dienyladdition of chiral nucleophiles synthesis

Lanthanide complexes 3-diketonate, chiral

Lanthanide complexes P-diketonate, chiral

Large chiral complexes

Manganese chiral Schiff base complex

Mannich using chiral palladium complexe

Meso-Epoxide ring opening chiral complex

Metal Complexes of Chiral Ligands

Metal carbene complexes chiral

Metal complexes, topologically chiral

Metallic complexes, chirality

Michael addition chiral metal complexes

Molecular complexes, chiral interactions

Molecular sieves, chiral metal complex

Molybdenum allyl complexes chiral

Molybdenum complexes chirality

Nickel complexes chiral surfaces

Octahedral Metal Complexes with Helical Chirality

Other Related Complexes with Chiral-at-Metal Centre

Oxidation chiral salen complexes

Palladium complexes chiral

Palladium complexes chiral squares

Pincer-type complexes chiral

Planar-chiral chromium complexe

Polymerization chiral metal complexes

Polymers containing chiral complexes

Propanoyl-iron complexes chiral

Ptopanoyl-iron complexes chiral

Resolution of a-Amino Acids by Chiral Polymer Complexes

Rhodium , chiral “binap” complexes

Rhodium , chiral “binap” complexes asymmetric hydrogenation with

Rhodium complexes axial chiral

Rhodium complexes chiral recognition

Rhodium complexes chirality transfer

Rhodium complexes, chiral

Rhodium ferrocenylphosphine complex, chiral

Rhodium/chiral diene complexes

Ruthenium , chiral “binap” complexes

Ruthenium catalysts chiral complexes

Ruthenium chiral arene complexes

Ruthenium complexes chiral chelating ligands

Ruthenium complexes chiral recognition

Ruthenium complexes chirality

Ruthenium-chiral bisphosphine complexes

Schiff bases, chiral metal complexes

Self-assembly chiral polynuclear complexes

Self-assembly of Chiral Polynuclear Complexes from Achiral Building Units

Silver complexes chiral

Some Examples of Chiral Organometallic Complexes and Asymmetric Catalysis

Stereoselectivity chiral rhodium complexes

Steric effects chiral complexes

Structure of Chiral Ferrocenylphosphines and their Transition-Metal Complexes

Sulfoxide complexes containing chiral

Sulfoxide complexes of chiral ligands

Supported complexes chiral supports

Synthesis of Chiral Nitridomanganese Complex

Tertiary phosphine-transition metal complexes chiral

The Chiral Acyl-Iron Complex

The Chirality of Polynuclear Transition Metal Complexes (Provent and

Titanium chiral complex

Titanium complexe chiral ligand

Transfer hydrogenation chiral metal complexes

Transient diastereomeric complexes chiral separation

Transition complexes, chiral

Transition metal compounds chiral manganese complex

Use of Chiral Lewis Acids and Transition Metal Complexes

Zeolites chiral complex

ZnF2--chiral diamine complex

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