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Complexes substitution

There are direct substitutions of possible interest that would not be feasible without drastic changes in the feed system or pressure. Thus if the available substitute for natural gas is, eg, a manufactured gas containing much CO, there would almost always be a mismatch of the WIs unless the fuel could be further modified by mixing with some other gaseous fuel of high volumetric heating value (propane, butane, vaporized fuel oil, etc). Moreover, if there are substantial differences in eg, as a result of the presence of considerable H2 as well as CO in the substitute gas, the variation in dame height and dashback tendency can also make the substitution unsatisfactory for some purposes, even if the WI is reproduced. Refinements and additional criteria are occasionally appHed to measure these and other effects in more complex substitution problems (10,85). [Pg.524]

In addition, NaOMe, and NaNH2, have also been employed. Applieation of phase-transfer conditions with tetra-n-butylammonium iodide showed marked improvement for the epoxide formation. Furthermore, many complex substituted sulfur ylides have been synthesized and utilized. For instance, stabilized ylide 20 was prepared and treated with a-D-a/lo-pyranoside 19 to furnish a-D-cyclopropanyl-pyranoside 21. Other examples of substituted sulfur ylides include 22-25, among which aminosulfoxonium ylide 25, sometimes known as Johnson s ylide, belongs to another category. The aminosulfoxonium ylides possess the configurational stability and thermal stability not enjoyed by the sulfonium and sulfoxonium ylides, thereby are more suitable for asymmetric synthesis. [Pg.4]

Several papers have appeared recently comparing various properties of carbonyl metal complexes substituted by various phosphines or phosphite ligands or isocyanides. Angelici and Ingemanson (4) studied the equilibrium... [Pg.53]

Another interesting aspect of reactivity within this class of complexes is interconversion of syn and anti isomers, as has been observed with Tc-PnAO complexes substituted at the central carbon of the propylene bridge [67], The same phenomenon has been described for DMSA complexes and will be discussed in the section on S-donor groups. [Pg.93]

Further cyclopropenones of more complex substitution are compiled in Ref.10). [Pg.19]

It is clear that reactions suitable for use in titrimetric procedures must be stoichiometric and must be fast if a titration is to be carried out smoothly and quickly. Generally speaking, ionic reactions do proceed rapidly and present few problems. On the other hand, reactions involving covalent bond formation or rupture are frequently much slower and a variety of practical procedures are used to overcome this difficulty. The most obvious ways of driving a reaction to completion quickly are to heat the solution, to use a catalyst, or to add an excess of the reagent. In the last case, a hack titration of the excess reagent will be used to locate the stoichiometric point for the primary reaction. Reactions employed in titrimetry may be classified as acid-base oxidation-reduction complexation substitution precipitation. [Pg.192]

The development of transition metal mediated asymmetric epoxidation started from the dioxomolybdcnum-/V-cthylcphcdrinc complex,4 progressed to a peroxomolybdenum complex,5 then vanadium complexes substituted with various hydroxamic acid ligands,6 and the most successful procedure may now prove to be the tetroisopropoxyltitanium-tartrate-mediated asymmetric epoxidation of allylic alcohols. [Pg.196]

Both mechanisms, termed the associative and dissociative v complex substitution mechanisms, proceed via n complex adsorbed aromatics (e.g., benzene) which occupy a position on the catalyst so that the plane of the ring is parallel to the catalyst surface [Eq. (7)] ... [Pg.103]

Since the associative and dissociative tt complex substitution mechanisms are not mutually exclusive, both may participate simultaneously in exchange reactions where deuterium oxide is the second reagent. It is therefore of interest to distinguish between the relative importance of these two mechanisms. [Pg.113]

The fact that an isotope effect of 1.7 0.1 is observed 38) in the benzene/deuterium oxide reaction at 30°C indicates that this reaction is the rate-determining step of the dissociative n complex substitution mechanism. In this respect the result agrees with the direct observations made by other investigators 41, 42), namely that unsaturated hydrocarbons chemisorb at a faster rate than their subsequent interactions with chemisorbed hydrogen. [Pg.115]

The more precise formulation of the transition complex of n complex substitution reactions makes it possible to write a reaction scheme [Eq. (17)] showing the possible interconnection of a number of hitherto unrelated hydrogenation and exchange mechanisms. [Pg.119]

It has been shown that the interpretation of catalytic reactions involving group VIII transition metals in terms of n complex adsorption possesses considerable advantages over classical theories by providing a link between theoretical parameters and chemical properties of aromatic reagents and catalysts. The concept has led to the formulation of a number of reaction mechanisms. In heavy water exchange the dissociative tt complex substitution mechanism appears to predominate it could also play a major role when deuterium gas is used as the second reagent. The dissociative mechanism resolves the main difficulties of the classical associative and dissociative theories, in particular the occurrence... [Pg.119]

The stabilisation is particularly marked in that not only is an extra (fourth) canonical state involved in the stabilisation of the o- and p-positive charge is located on oxygen, are inherently more stable than their other three complementary forms, in which the positive charge is located on carbon (cf. 48a— 48c, and 49a— 49c). This effect is sufficiently pronounced to outweigh by far the electron-withdrawing inductive (polar) effect also operating in these two cr complexes, substitution is thus almost completely o-lp- ( 1% of the m-isomer is obtained in the nitration of PhOMe), and much more rapid than on benzene itself (kcsH50Me/fcc 6H = 9-7x 10 for chlorination). [Pg.154]

For (CO) CoMR3 complexes, substitution of a carbonyl residue requires very drastic conditions and optically active phosphine-substituted complexes could not be obtained in this manner. In Section 2.2.2 we have described an alternative synthesis of L(CO)3CoGeMePh 1-Np [L = PPh3, P(OPh)3]. [Pg.91]


See other pages where Complexes substitution is mentioned: [Pg.47]    [Pg.588]    [Pg.616]    [Pg.98]    [Pg.126]    [Pg.224]    [Pg.138]    [Pg.154]    [Pg.139]    [Pg.157]    [Pg.40]    [Pg.378]    [Pg.712]    [Pg.183]    [Pg.619]    [Pg.303]    [Pg.242]    [Pg.95]    [Pg.95]    [Pg.95]    [Pg.99]    [Pg.100]    [Pg.102]    [Pg.103]    [Pg.104]    [Pg.113]    [Pg.114]    [Pg.118]    [Pg.118]    [Pg.119]    [Pg.119]   
See also in sourсe #XX -- [ Pg.680 ]

See also in sourсe #XX -- [ Pg.287 , Pg.288 ]

See also in sourсe #XX -- [ Pg.506 , Pg.507 , Pg.508 ]

See also in sourсe #XX -- [ Pg.287 , Pg.288 ]




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1- -sparteine complexes substitution

18-electron complexes ligand substitution

18-electron complexes ligand substitution mechanism

2-Cyclohexenone, 5-substituted via arene-metal complexes

2’- -complexes, allylic substitutions

6-Substituted 2,2 -bipyridines, platinum complexes

Acceptor-Substituted Carbene Complexes

Acetic acid complexes, substituted

Acetylene complexes ligand substitution

Acetylene complexes substitution reactions

Alkane complexes dissociative substitutions

Alkene complexes substitution

Alkenes vinyl substitution with palladium complexes

Allylic Substitution Reactions via n-Allyl Complexes

Allylic substitutions iridium complexes

Arene complexes electrophilic substitution

Arene complexes nucleophilic substitution

Aromatic Substitution by Metal Catalysis or Other Complex Mechanisms

Aromatic substitution reactions, role charge-transfer complexes

Aryl complexes, iodide substitution

Aryl-copper complexes, substitution

Associative substitution mechanism square planar complexes

Associative substitutions 17-electron complexes

Associative substitutions complexes

Asymmetric Synthesis Based on Sulfonimidoyl-Substituted Allyltitanium Complexes

CARBONYLS, PHOSPHINE COMPLEXES, AND LIGAND SUBSTITUTION REACTIONS

Carbene complexes carbonyl substitution

Carbene complexes nonheteroatom-substituted

Carbene complexes nucleophilic substitutions

Carbene complexes, acceptor-substitute

Carbene complexes, heteroatom-substituted

Carbonyl --complexes, preparation substitution methods

Carbonyl complexes substitution reactions

Carbonyl complexes, hydrosilylation substitution

Carbonyl substituted metal complexes

Carbonylate complexes substitution reactions

Cationic palladium complexes substitution

Chloroarene complexes substitution polymerization

Chromium complexes ligand substitution reactions

CoCl2 complexes with 4-substituted

Cobalt complexes atom-transfer substitution reactions

Cobalt complexes ligand substitution

Cobalt complexes substitution reactions

Cobalt complexes, ligand substitution reactions

Complex substitution reactions

Coordination complex reactivity substitution reactions

Copper complexes substitution

Cyanide exchange substituted complexes

Cyclobutadiene complexes substitution

Cyclopalladated complexes vinyl substitutions

Dissociative substitution mechanisms octahedral complexes

Dissociative substitution reactions 18-electron complexes

Dithiolate complexes substitution reactions

Electron-transfer complexes substitutents

Electrophilic Aromatic Substitutions via Sigma Complexes (Ar-SE Reactions)

Electrophilic Substitution in Metal Complexes

Electrophilic aromatic substitution sigma complex

Electrophilic substitution 1 - -sparteine complexes

Electrophilic substitution square planar complexes

Electrophilic substitution, acetylacetone complexes

Electrophilic substitution, aromatic complexing with substituent

Encounter complex substitution

Fischer carbene complexes nucleophilic substitution

Five-coordinate complexes substitution reactions

Five-coordinated complexes Substitution

Four-coordinate complexes substitution reactions

Four-coordinate complexes substitution reactions, dissociative activation

Four-coordinate complexes substitution reactions, nucleophilicity

Generation of Acceptor-Substituted Carbene Complexes

Generation of Heteroatom-Substituted Carbene Complexes

Generation of Non-Heteroatom-Substituted Carbene Complexes

Gold complexes substitution reactions

Heterocyclic complexes, substitution with

Heterocyclic-substituted complexes

Heterocyclic-substituted complexes metallo-1,2-enedithiolates

Hydride complexes ligand substitutions

Hydroxy-substituted -complexes

Indole substituted), complexes

Iron complex ligand substitution

Iron complexes ligand substitution reactions

Iron complexes oxidative substitution

Iron complexes substitution reactions

Iron diimine complexes substitution reactions

Isocyanide-substituted complexes

Lead, arylvinyl substitutions palladium complexes

Ligand Substitution in Transition Metal ir-Complexes

Ligand Substitution in Transition Metal w-Complexes

Ligand substitution in octahedral complexes

Ligand substitution in square planar complexes

Ligand substitution mechanisms complexes

Ligand substitution reactions high oxidation state complexes

Ligand substitution reactions inert octahedral complexes

Ligand substitution reactions rhodium complexes

Ligand substitution reactions ruthenium complexes

Ligand substitution reactions square-planar complexes

Ligand substitution reactions transition metal complexes

Ligand substitution, metals/metal complexes

Magnesium, arylvinyl substitutions palladium complexes

Mechanisms of Substitution Reactions Metal Complexes

Meisenheimer complexes substitution

Metal complexes ligand substitution mechanisms

Metal complexes square planar, substitution

Metal complexes—continued substitution reactions

Metal-carbene complexes alkoxy substituted

Metal-carbene complexes amino substituted

Metal-carbene complexes ligand substitution reactions

Metal-carbonyl complexes, substitution

Metal-carbonyl complexes, substitution reactions

Mixed-ligand complexes substitution

Molybdenum complexes ligand substitution

Molybdenum complexes substitution reactions

Monomeric complexes chloroarene substitution polymerization

Nickel complexes ligand substitution reactions

Nickel complexes substitution

Nitrogen-substituted carbene complexes

Nitrogen-substituted carbene complexes reactivity

Nitrogen-substituted carbene complexes structure

Nitrogen-substituted carbene complexes synthesis

Nitrophenols substituted), complexes

Non-Heteroatom-Substituted Carbene Complexes

Nucleophilic Substitution Reactions via Meisenheimer Complexes

Nucleophilic aromatic substitution Meisenheimer complexes

Nucleophilic aromatic substitution aryl-copper complexes

Nucleophilic aromatic substitution intermediate complexes

Nucleophilic substitution in octahedral complexes

Nucleophilic substitution in square planar complexes

Nucleophilic substitution process Meisenheimer complex

Nucleophilic substitution reactions complexes

Octahedral Substitution Reactions. Labile and Inert Complexes

Octahedral complexes, substitution

Octahedral complexes, substitution reactions

Olefin complexes dissociative ligand substitutions

Olefin complexes, substitution reactions

Olefin complexes, substitution reactions platinum

Olefin complexes, substitution reactions rhodium

Osmium complexes substituted

Osmium complexes substitution reactions

Osmium-substituted carbene complexes

Outer-sphere complex Substitution reactions

Outer-sphere complex formation substitution reactions

Palladium complexes ligand substitutions

Palladium complexes substitution

Palladium complexes substitution reactions

Peptide-metal complexes substitution reactions

Phenols substituted), complexes

Phosphine substituted, complexes

Photochemical substitution reactions transition metal complexes

Phthalocyanine complexes alkylthio-substituted

Phthalocyanine complexes octakis-substituted

Platinum complexes dissociative substitution

Platinum complexes substitution reactions

Platinum complexes, substitution

Platinum complexes, substitution reactions acetylenes

Polypeptide complexes, substitution

Polypeptide complexes, substitution reactions

Pre-lab 4.1 Substitution Properties of Metal Ion Complexes in

Pyridine, 4-substituted, complexes with

Pyrimidine substituted), complexes

Rhenium complexes substitution reactions

Rhodium complexes substitution reactions

Rhodium complexes substitutions

Ruthenium complexes substitution reactions

Ruthenium complexes substitutions

Se-Substituted Carbene Complexes

Selective Aromatic Substitution Directed by Cyclodextrin Complexing

Sodium alkyl thiolates, reaction with halogen substituted metal complexes

Square complexes, substitution reactions

Square planar complex substitution

Square-planar complexes dissociative substitution

Square-planar substitution reactions complexes

Square-planar, 16-electron complexes associative substitutions

Square-planar, 16-electron complexes substitutions

Square-pyramidal complexes Substitution

Substituted pentacyanoferrate complexes

Substitution Polymerization of Chloroarene Complexes

Substitution Processes in Dimeric Metal Complexes

Substitution Reactions of 18-Electron Complexes

Substitution Reactions of Inert-Metal Complexes— oordination Numbers 4 and

Substitution Reactions of Inert-Metal Complexes— oordination Numbers 6 and Above Chromium House ntroduction

Substitution Reactions of Inert-Metal Complexes— oordination Numbers 6 and Above Cobalt Hay Aquation

Substitution Reactions of Linear Complexes

Substitution Reactions of Tetrahedral Complexes

Substitution Tetrahedral complexes

Substitution and racemization in octahedral complexes

Substitution at Square-Planar Complexes

Substitution ferrate complex

Substitution in 17-Electron Mononuclear Complexes

Substitution in Other Mononuclear Complexes

Substitution in Polynuclear Complexes

Substitution in Square Planar Complexes

Substitution in cis complexes

Substitution in square planar complexe

Substitution in trans complexes

Substitution inert labile complexes

Substitution mechanisms octahedral complexes

Substitution mechanisms square planar complexes

Substitution of Weakly Bound Ligands in 18-Electron Complexes

Substitution on Complexes of Alkali and Alkaline Earth Metal Ions

Substitution on Complexes of Oxo Metal Ions

Substitution on Complexes of the Trivalent Lanthanide Ions

Substitution on Complexes of the Trivalent Main Group Metal Ions

Substitution reactions in octahedral complexes

Substitution reactions in square planar complex

Substitution reactions metal alkene complexes from

Substitution reactions of inert complexes

Substitution reactions of octahedral complexes

Substitution reactions of square-planar complexes

Substitution reactions on metal complexes

Substitution reactions, arene --complexes

Substitution reactions, transition metal complexes

Substitution shifts, halide complexes

Substitution, electrophilic complexes

Substitution, electrophilic encounter complexes

Substitution-inert complexes

Substitutions on square-planar complexes

Sulfonimidoyl-Substituted Bis (allyl) titanium Complexes

Sulfonimidoyl-Substituted Mono (allyl) titanium Complexes

Sulfonimidoyl-substituted allyltitanium complexes

Sulfur-substituted carbene complexes

Synthesis vinyl substitution with palladium complexes

Thallium complexes ligand substitutions

Trans complexes, substitution

Triruthenium complexes, axial ligand substitution

Tris-Complexes of 3-Substituted Camphor

Vinyl substitutions palladium complexes

Wheland complexes substitution

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