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Bidentates

In summary, the effects of a number of important parameters on the catalysed reaction between 2.4 and 2.5 have been examined, representing the first detailed study of Lewis-acid catalysis of a Diels-Alder reaction in water. Crucial for the success of Lewis-acid catalysis of this reaction is the bidentate character of 2.4. In Chapter 4 attempts to extend the scope of Lewis-acid catalysis of Diels-Alder reactions in water beyond the restriction to bidentate substrates will be presented. [Pg.63]

The coordination of bidentate ligands is generally more efficient than expected on the basis of the binding affinity of monodentate analogues. This is referred to as the chelate effect. For reviews, see (a) Schwarzenbach, G. Helv. Chim. Acta, 1952, 35, 2344 (b) reference 75. [Pg.73]

Consequently, in initial attempts to extend the scope, we aimed to identify catalysis of Diels-Alder reactions of other bidentate dienophiles in water. This task turned out to be more difficult than expected Scheme 4.5 provides a collection of potentially chelating dienophiles that all failed to... [Pg.110]

Careful examination of literature reporting Lewis-acid catalysis of Diels-Alder reactions in combination with kinetic investigations indicate that bidentate (or multidentate) reactants are required in order to ensure efficient catalysis in water. Moreover, studies of a number of model dienophiles revealed that a potentially chelating character is not a guarantee for coordination and subsequent catalysis. Consequently extension of the scope in this direction does not seem feasible. [Pg.119]

The effects of these ligands on the second-order rate constants for the Cu (ligand) catalysed reaction of Ic with 2 are modest In contrast, the effects on IC2 are more pronounced. The aliphatic Oramino acids induce an approximately two-fold reduction of Iv relative to for the Cu" aquo ion. For the square planar coordinated copper ions this effect is expected on the basis of statistics. The bidentate ligands block half the sites on the copper centre. [Pg.175]

The carbonylation of aryl iodides in the presence of terminal alkynes affords the acyl alkynes 565. Bidentate ligands such as dppf give good results. When PhjP is used, phenylacetylene is converted into diphenylacetylene as a main product[4l5]. Triflates react similarly to give the alkynyl ketones 566[4I6], In... [Pg.205]

Allylic acetates react with ketene silyl acetals. In this reaction, in addition to the allylated ester 468, the cyclopropane derivative 469. which is formed by the use of bidentate ligands, is obtained[303]. Formation of a cyclopropane derivative 471 has been observed by the stoichiometric reaction of the 7r-allylpal-... [Pg.352]

When a bidentate phosphine is used as a ligand for the reaction of J-keto esters or /i-diketones, no dimerization takes place. Only a 2-butenyl group is introduced to give 68[49,62], Substituted dienes such as isoprene, 1,3-cyclohexa-diene, and ocimene react with carbon nucleophiles to give a mixture of possible regio- and stereoisomers of 1 1 adducts when dppp is used as a ligand[63,64]. [Pg.433]

The red tetrathiomolybdate ion appears to be a principal participant in the biological Cu—Mo antagonism and is reactive toward other transition-metal ions to produce a wide variety of heteronuclear transition-metal sulfide complexes and clusters (13,14). For example, tetrathiomolybdate serves as a bidentate ligand for Co, forming Co(MoSTetrathiomolybdates and their mixed metal complexes are of interest as catalyst precursors for the hydrotreating of petroleum (qv) (15) and the hydroHquefaction of coal (see Coal conversion processes) (16). The intermediate forms MoOS Mo02S 2> MoO S have also been prepared (17). [Pg.470]

The chain-growth catalyst is prepared by dissolving two moles of nickel chloride per mole of bidentate ligand (BDL) (diphenylphosphinobenzoic acid in 1,4-butanediol). The mixture is pressurized with ethylene to 8.8 MPa (87 atm) at 40°C. Boron hydride, probably in the form of sodium borohydride, is added at a molar ratio of two borohydrides per one atom of nickel. The nickel concentration is 0.001—0.005%. The 1,4-butanediol is used to solvent-extract the nickel catalyst after the reaction. [Pg.439]

A further improvement in platinum catalysis is claimed from use of tin(Il) haUde and phosphine ligands which are rigid bidentates, eg, l,2-bis(diphenylphosphinomethyl)cyclobutane (27). High rates for a product containing 99% linear aldehyde have been obtained. However, a pressure of 10 MPa (1450 psi) H2 CO is requited. [Pg.470]

These hydrated salts contain bidentate carbonate ligands and no water molecules are bound directly to the central metal atom. The only single-crystal x-ray diffraction studies available are those for salts of (4) (52—54) and the mineral tuliokite [128706 2-3], Na2BaTh(C03)2 -6H20], which contains the unusual Th(C02) 2 anion (5) (55). [Pg.38]

Peroxidic Compounds. When hydrogen peroxide is added to a solution of titanium(IV) compounds, an intense, stable, yellow solution is obtained, which forms the basis of a sensitive method for determining small amounts of titanium. The color probably results from the peroxo complex [Ti(02)(0H)(H20)J, and crystalline salts such as K2[Ti(02)(S0 2] H20 can be isolated from alkaline solutions. The peroxo ligand is bidentate the two oxygen atoms ate equidistant from the titanium (98). [Pg.127]

An acylate group is potentially a bidentate ligand. It may bond once or twice to one titanium, or bridge two titanium atoms as shown. [Pg.149]

In titanium acylates, the carboxylate ligands are unidentate, not bidentate, as shown by ir studies (333,334). The ligands are generally prepared from the hahde and silver acylate (335). The ben2oate is available also from a curious oxidative addition with ben2oyl peroxide (335—338) ... [Pg.160]

The known uranium(VI) carbonate soHds have empirical formulas, 1102(003), M2U02(C03)2, and M4U02(C03)3. The soHd of composition 1102(003) is a well-known mineral, mtherfordine, and its stmcture has been determined from crystals of both the natural mineral and synthetic samples. Rutherfordine is a layered soHd in which the local coordination environment of the uranyl ion consists of a hexagonal bipyramidal arrangement of oxygen atoms with the uranyl units perpendicular to the orthorhombic plane. Each uranium atom forms six equatorial bonds with the oxygen atoms of four carbonate ligands, two in a bidentate manner and two in a monodentate manner. [Pg.327]


See other pages where Bidentates is mentioned: [Pg.395]    [Pg.2703]    [Pg.47]    [Pg.49]    [Pg.59]    [Pg.82]    [Pg.84]    [Pg.85]    [Pg.107]    [Pg.164]    [Pg.177]    [Pg.3]    [Pg.4]    [Pg.126]    [Pg.129]    [Pg.136]    [Pg.198]    [Pg.456]    [Pg.460]    [Pg.468]    [Pg.511]    [Pg.70]    [Pg.120]    [Pg.331]    [Pg.62]    [Pg.63]    [Pg.434]    [Pg.13]    [Pg.207]    [Pg.37]    [Pg.39]    [Pg.119]    [Pg.326]   


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1.3- Bidentate nucleophiles

2-Amino-4-picoline , bidentate ligands

2-Aminopyridine , bidentate ligands

Acetate ligand, bidentate

Actinides bidentate extraction

Alkyne complexes bidentate donor ligands

Amides Bidentate ligands

Amines bidentate

Amino acids bidentate coordination

Anionic bidentate pyrazolate

Anions, bidentate

Application Cross-Coupling with a Bidentate Pd Complex

Arsines bidentate

Arsines bidentate tertiary

Aryl halides bidentate diphosphine ligands

As2-Bidentates

Asymmetric hydrogenation bidentate ligands

Asymmetric reactions with bidentate phosphines

Azo compounds bidentate

Benzene-1,2-diolato bidentate ligand

Bidentate

Bidentate 1,2-diaminoethane

Bidentate 1,2-diaminopropane

Bidentate 2,3-diaminobutane

Bidentate Entering Groups

Bidentate Groups

Bidentate Leaving Groups

Bidentate Ligands Containing 1,4-Disubstituted

Bidentate Ligands Containing a Heteroatom-Phosphorus Bond

Bidentate Ligands Forming Four-Membered Rings with Silicon

Bidentate Ligands for Enantioselective Enamide Reduction

Bidentate N-, O- ligands

Bidentate N-Heterocyclic Carbene Ligands Incorporating Oxazoline Units

Bidentate NHC

Bidentate NHCs

Bidentate Nitrogen Donor Complexes

Bidentate P-ligands

Bidentate Schiff-base ligands

Bidentate activation

Bidentate aliphatic amines

Bidentate amines photochemistry

Bidentate and tridentate

Bidentate anions, bridging

Bidentate base

Bidentate binuclear bridging complex

Bidentate bis

Bidentate bisphosphine ligands

Bidentate bridges

Bidentate carbonate

Bidentate catalysts

Bidentate chelate

Bidentate chelation

Bidentate chelation (also

Bidentate chiral auxiliaries

Bidentate complex ions, tris

Bidentate compounds

Bidentate configuration

Bidentate coordination

Bidentate counterions

Bidentate cyclohexanediamine

Bidentate diamine ligands

Bidentate dienophiles, Diels-Alder

Bidentate dienophiles, Diels-Alder reactions

Bidentate diphosphine

Bidentate diphosphines dppm)

Bidentate diphosphite

Bidentate diphosphites

Bidentate dithiophosphates

Bidentate donor ligands

Bidentate extraction

Bidentate formate

Bidentate formate ligand, vibrations

Bidentate glutamate ligands

Bidentate hydrogen bond

Bidentate imidazolium

Bidentate ligand structures

Bidentate ligand, chiral

Bidentate ligands

Bidentate ligands cobalt complexes

Bidentate ligands complexes

Bidentate ligands dithiocarbamate complexes

Bidentate ligands fluorous-tagged

Bidentate ligands group

Bidentate ligands restricting function

Bidentate ligands salicylato

Bidentate ligands transition metals

Bidentate ligands, cyanide-bridged complexes

Bidentate ligands, delocalized bond

Bidentate ligands, delocalized bond system

Bidentate ligands, geometry actinide complexes with

Bidentate ligands, molybdenum

Bidentate ligands, molybdenum complexes

Bidentate ligands, mononuclear complexe

Bidentate ligands, supramolecular catalysis

Bidentate ligands, xanthate structures

Bidentate mode

Bidentate neutral organophosphorus

Bidentate neutral organophosphorus compounds

Bidentate nitrates

Bidentate nitrogen

Bidentate nitrogen ligands

Bidentate nucleophile

Bidentate nucleophiles cyanide

Bidentate nucleophiles enamines

Bidentate oxygen-donor extractants

Bidentate palladium complexes

Bidentate phenanthroline

Bidentate phosphane ligands

Bidentate phosphine ligand

Bidentate phosphite ligand

Bidentate phosphite-phosphoramidite ligand

Bidentate phosphonites

Bidentate phosphorous

Bidentate phosphorus ligand, replacement

Bidentate phosphorus ligands

Bidentate phosphorus ligands BINAP

Bidentate pyrazolyl-based ligands

Bidentate siderophores

Bidentate species

Bidentate species conformers

Bidentate sulfur-donor ligands

Bidentate surface complexes

Bidentate surface complexes inner-sphere

Bidentate system

Bidentate-based systems

Bidentate-binuclear

Bidentate-mononuclear

Bidentates Sulfur-oxygen ligands

Bidentates amine group donors

Bidentates hydroxylamine group donors

Bidentates mixed donor atoms

Bidentates nitrogen-oxygen ligands

Bidentates nitrogen-sulfur ligands

Bidentates oxime group donors

Bidentates selenium-nitrogen ligands

Bidentates selenium-oxygen ligands

Bidentates selenium-sulfur ligands

Bidentates thioether donor groups

Bidentates thiol group donors

Borates and Boronates from Bidentate Ligands

Bridge bidentate coordination

Bridge, bidentate-tridentate

Bridging Bidentate Ligands

C2-chiral bidentate fluoroarylphosphinite C5Me5)Ru

Catalyst bidentate ligands

Central chirality bidentate ligands

Chiral bidentate phosphine

Chiral bidentate phosphorus ligands

Chiral bidentate phosphorus ligands BINAP

Chiral bidentate tertiary

Chiral ligands bidentate phosphine

Chromium complexes bidentate

Cobalt complexes bidentate

Complex bidentate

Complexes Supported by Bidentate Ligands with a Delocalized Bond System

Complexes of Bis-Bidentate B(pz)J

Coordination compounds bidentate

Coordination compounds bidentate ligands

Copper catalysts bidentate ligands

Diamines bidentate

Diphosphines bidentate

Diphosphinites ligands, bidentate

Ditopic bidentate ligand

Donor bidentate sulfur

Dppe bidentate ligand

Eight-coordinate actinide complexes with bidentate ligands, geometry

Enolate bidentate

Esters bidentate

Ethers, protonated bidentate complexes

Experiment 5.1 Synthesis of Tris(bidentate

Experiment 5.2 Visible Spectroscopy of Tris(bidentate

Extractants bidentate

First-Generation Ruthenium Indenylidene Catalysts Bearing a Bidentate Dichalcogenoimidodiphosphinate Ligand

First-Generation Ruthenium Indenylidene Catalysts Bearing a Bidentate Schiff Base Ligand

Formazans bidentate

General Syntheses of Tris(bidentate) Complexes

Heck reaction with bidentate phosphines

Heterocycles bidentate

Heterodimeric bidentate

Indium complexes bidentate

Lewis acids, bidentate

Lewis bidentate

Library bidentate phosphines

Ligands bidentate aspartate

Ligands bidentate covalent

Ligands bidentate dppp

Ligands neutral bidentate

Ligation of zeolite exchanged transition ions with bidentate aza ligands

Lithium Bidentate

Manganese complexes bidentate

Metal alkoxides reactions with bidentate ligands

Metallomesogens with Bidentate Ligands

Molybdenum catalysts bidentate ligands

Molybdenum complexes bidentate phosphines

Molybdenum complexes reaction with bidentate ligands

Monomeric eight-coordinate actinide complexes with bidentate ligands

Multi-bidentate ligands

N-Bidentates

Neutral Mono-and Bidentate Nitrogen Bases

Neutral bidentate complexes

Nitrides bidentate ligands

Nitrogen-oxygen ligands bidentate

Organophosphorus bidentate

Osmium complexes bidentate

Other Mixed-Donor Bidentate Ligands

Oxidative addition bidentate diphosphine ligands

P-Bidentates

Palladium complexes bidentate diphosphine ligands

Palladium complexes bidentate ligands

Paracyclophanes bidentate ligands

Phosphate bidentate adsorption

Phosphate compounds, bidentate

Phosphine complexes bidentate, technetium

Phosphines bidentate

Phosphines bidentate tertiary

Phosphoramidites bidentate

Phthalocyanines bidentate

Planar chiral compounds bidentate ligands

Polypyrazolylborates bidentate

Pyrocatechol bidentate

Reaction mechanism bidentate ligands

Reactions of Bidentate Phosphines with Metallaboranes Possible Routes to Linked Cluster Systems

Reversible bidentate-tridentate

Rhenium complexes bidentate phosphines

Rhodium Hydroformylation Catalysts with Bidentate Ligands

Rhodium complexes bidentate amines

Rhodium complexes bidentate anions

Ruthenium bidentate Schiff base ligand

Ruthenium complexes bidentate

Ruthenium complexes bidentate heterocycles

S-Bidentates

Salicylaldimines bidentate

Schiff bases bidentate

Self supramolecular bidentate ligands

Stibines bidentate tertiary

Sulfides bidentate

Sulfites bidentate

Sulfones bidentate

Sulfoxides bidentate

Supramolecular Construction of Chelating Bidentate Ligand Libraries through Hydrogen Bonding Concept and Applications in Homogeneous Metal Complex Catalysis

Supramolecular bidentate ligands

Surface bidentate

Tellurium complexes bidentate ligands

Terpyridine, bidentate

Titanium complexes bidentate

Transition Metal Complexes Containing Bidentate Phosphine Ligands

Trigonal twist angle, tris-bidentate

Trigonal twist angle, tris-bidentate complex

Triphosphorus bidentate phosphine

Triphosphorus bidentate phosphine phosphoramidite ligands

Tris bidentate complexes

Tris-bidentate metal complex

Tris-bidentate metal complex conformation

Tungsten bidentate

Water-soluble bidentate

With dppe bidentate ligand

With dppm bidentate ligand

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