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Bidentate ligands, 82-3

Two monodentate ligands can be combined to one bidentate ligand. According to the chelate effect, the complexes are expected to be even stabler. This is not so crucial since it is almost impossible to replace even monodentate ligands but more importantly, the rate of coordination is expected to be faster. Hence, the ligand concentration to achieve quantitative labelling or complex formation [Pg.17]


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]

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]

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]

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]

Tartar emetic was the subject of controversy for many years, and a variety of iacorrect stmctures were proposed. In 1966, x-ray crystallography showed that tartar emetic contains two antimony(III) atoms bridged by two tetranegative D-tartrate residues acting as double bidentate ligands to form dipotassium bis[D-p.-(2,3-dihydroxybutanedioato)]diantimonate [28300-74-5] (41). [Pg.205]

A hydroxyl group is situated ortho to a carboxyl group which as a bidentate ligand is terminally metallized on the fiber when aftertreated with dichromate. An example is Alizarine Yellow GG [584-42-9] (50) (Cl Mordant Yellow 1 Cl 14025). Cr(III) has a coordination number of six, and therefore normally two dye molecules of the sahcyhc type are chelated to the metal ion. [Pg.437]

Consider the equiUbria in an aqueous system composed of a bidentate ligand HA, eg, the enol form of acetylacetone, and a tetracoordinate metal, stmcture (8). The equations are... [Pg.387]

Metal ion complexation rates have been studied by the T-jump method. ° Divalent nickel and cobalt have coordination numbers of 6, so they can form complexes ML with monodentate ligands L with n = 1—6 or with bidentate ligands, n = 1-3. The ligands are Bronsted bases, and only the conjugate base form undergoes coordination with the metal ion. The complex formation reaction is then... [Pg.150]

The CK" ion can act either as a monodentate or bidentate ligand. Because of the similarity of electron density at C and N it is not usually possible to decide from X-ray data whether C or N is the donor atom in monodentate complexes, but in those cases where the matter has been established by neutron diffraction C is always found to be the donor atom (as with CO). Very frequently CK acts as a bridging ligand - CN- as in AgCN, and AuCN (both of which are infinite linear chain polymers), and in Prussian-blue type compounds (p. 1094). The same tendency for a coordinated M CN group to form a further donor-aceeptor bond using the lone-pair of electrons on the N atom is illustrated by the mononuclear BF3 complexes... [Pg.322]

A few cases of optical isomerism are known for planar and tetrahedral complexes involving unsymmetrical bidentate ligands, but by far the most numerous examples are afforded by octahedral compounds of chelating ligands, e.g. [Cr(oxalate)3] and [Co(edta)] (Fig. 19.13). [Pg.919]

Diphenyl-2-thienylphosphine is expected to serve as a bidentate ligand by coordination of either the phosphorus and sulfur atoms or the phosphorus atom and TT-electrons of the heteroring. Reaction of this phosphine with [Rc2(CO)lo] yields the species where both the sulfur and phosphorus atoms serve as the donor sites (960M786). [Pg.18]

Complexes with chiral heterocycles possessing P-containing substituents as P-mono- andP,N-bidentate ligands and their use in homogeneous asymmetric catalysis 98KK883. [Pg.219]

Chiral P-heterocycles as P-mono- and P,N-bidentate ligands in the synthesis of coordination compounds and homogeneous asymmetric catalysis 98KK883. [Pg.271]

Reactions of the metallocene derivatives of molybdenum with pyrazole lead to the mononuclear complexes of the type 22. Structure 22 shows that it cannot be used as a ligand for the preparation of dinuclear complexes owing to geometric constraints [80JOM( 197)291 83JOM(253)53]. In acetone, an unusual complex 23 is formed [83JOM(253)53]. The bidentate ligand is the product of the reaction of pyrazole and acetone. [Pg.163]


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2-Amino-4-picoline , bidentate ligands

2-Aminopyridine , bidentate ligands

Acetate ligand, bidentate

Alkyne complexes bidentate donor ligands

Amides Bidentate ligands

Aryl halides bidentate diphosphine ligands

Asymmetric hydrogenation bidentate ligands

Benzene-1,2-diolato bidentate ligand

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 P-ligands

Bidentate Schiff-base ligands

Bidentate bisphosphine ligands

Bidentate diamine ligands

Bidentate donor ligands

Bidentate formate ligand, vibrations

Bidentate glutamate ligands

Bidentate ligand structures

Bidentate ligand, chiral

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 nitrogen ligands

Bidentate phosphane ligands

Bidentate phosphine ligand

Bidentate phosphite ligand

Bidentate phosphite-phosphoramidite ligand

Bidentate phosphorus ligand, replacement

Bidentate phosphorus ligands

Bidentate phosphorus ligands BINAP

Bidentate pyrazolyl-based ligands

Bidentate sulfur-donor ligands

Bidentates

Bidentates Sulfur-oxygen ligands

Bidentates nitrogen-oxygen ligands

Bidentates nitrogen-sulfur ligands

Bidentates selenium-nitrogen ligands

Bidentates selenium-oxygen ligands

Bidentates selenium-sulfur ligands

Borates and Boronates from Bidentate Ligands

Bridging Bidentate Ligands

Catalyst bidentate ligands

Central chirality bidentate ligands

Chiral bidentate phosphorus ligands

Chiral bidentate phosphorus ligands BINAP

Chiral ligands bidentate phosphine

Complexes Supported by Bidentate Ligands with a Delocalized Bond System

Coordination compounds bidentate ligands

Copper catalysts bidentate ligands

Diphosphinites ligands, bidentate

Ditopic bidentate ligand

Dppe bidentate ligand

Eight-coordinate actinide complexes with bidentate ligands, geometry

First-Generation Ruthenium Indenylidene Catalysts Bearing a Bidentate Dichalcogenoimidodiphosphinate Ligand

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

Ligands bidentate aspartate

Ligands bidentate covalent

Ligands bidentate dppp

Ligands neutral bidentate

Ligation of zeolite exchanged transition ions with bidentate aza ligands

Metal alkoxides reactions with bidentate ligands

Metallomesogens with Bidentate Ligands

Molybdenum catalysts bidentate ligands

Molybdenum complexes reaction with bidentate ligands

Monomeric eight-coordinate actinide complexes with bidentate ligands

Multi-bidentate ligands

Nitrides bidentate ligands

Nitrogen-oxygen ligands bidentate

Other Mixed-Donor Bidentate Ligands

Oxidative addition bidentate diphosphine ligands

Palladium complexes bidentate diphosphine ligands

Palladium complexes bidentate ligands

Paracyclophanes bidentate ligands

Planar chiral compounds bidentate ligands

Reaction mechanism bidentate ligands

Rhodium Hydroformylation Catalysts with Bidentate Ligands

Ruthenium bidentate Schiff base ligand

Self supramolecular bidentate ligands

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

Supramolecular bidentate ligands

Tellurium complexes bidentate ligands

Transition Metal Complexes Containing Bidentate Phosphine Ligands

Triphosphorus bidentate phosphine phosphoramidite ligands

With dppe bidentate ligand

With dppm bidentate ligand

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