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Alkylated metals

Ketenes can react in several ways with organometaUic compounds and complexes. They can add as ligands to coordinated metals forming stable ketene, ketenyl, and ketenyfldene complexes. Ketenes can be inserted into metal—hydride, metal—alkyl, metal—OR, and metal—NR2 bonds, react with metal—oxide complexes, and with coordinated Hgands. This chemistry has been reviewed (9,51). [Pg.475]

Mixed-Metal Systems. Mixed-metal systems, where a zirconium alkyl is formed and the alkyl group transferred to another metal, are a new apphcation of the hydrozirconation reaction. These systems offer the advantages of the easy formation of the Zr—alkyl as well as the versatiUty of alkyl—metal reagents. For example, Cp2ZrRCl (R = alkyl or alkenyl) reacts with AICI3 to give an Al—alkyl species which may then be acylated with... [Pg.440]

The most important reaction with Lewis acids such as boron trifluoride etherate is polymerization (Scheme 30) (72MI50601). Other Lewis acids have been used SnCL, Bu 2A1C1, Bu sAl, Et2Zn, SO3, PFs, TiCU, AICI3, Pd(II) and Pt(II) salts. Trialkylaluminum, dialkylzinc and other alkyl metal initiators may partially hydrolyze to catalyze the polymerization by an anionic mechanism rather than the cationic one illustrated in Scheme 30. Cyclic dimers and trimers are often products of cationic polymerization reactions, and desulfurization of the monomer may occur. Polymerization of optically active thiiranes yields optically active polymers (75MI50600). [Pg.146]

Benzimidazole, 2-alkoxy-l-methyl-transalkylation, 5, 443 Benzimidazole, 1-alkyl-metal derivatives, 5, 448 reactions... [Pg.536]

Imidazole, 4-alkyl-synthesis, 5, 482 Imidazole, 5-alkyl-synthesis, 5, 481 Imidazole, N-alkyl-metallation, 5, 415-416 reactions, 5, 449-450 synthesis, 5, 387 Imidazole, 1 -alkyl-5-amino-synthesis, 5, 462... [Pg.649]

Pyrophoric alkyl metals Carbonylpotassium Pyrophoric metal Triethylarsine... [Pg.189]

Jod-Verbindungen setzen sich elektrolytisch oft zu dimeren Kohlenwasserstoffen und Alkyl-metall-Verbindungen um (s. S. 624, 677ff.). In DMF werden jedoch aus Jod-alka-nen neben Alkanen auch Alkene gebildet6 (vgl. a. Bd. V/la, S. 290). [Pg.623]

It is shown by Grossmann that for his phenyl compounds the results are qualitatively the same in the presence and in the absence of strong radiation doses, yet the results of Nowak and various others show that for alkyl metals radiation effects are more important. [Pg.74]

Reductive Elimination from Alkyl-Metal-NHC Complexes... [Pg.300]

Abstract Significant advances have been made in the study of catalytic reductive coupling of alkenes and alkynes over the past 10 years. This work will discuss the progress made in early transition metal and lanthanide series catalytic processes using alkyl metals or silanes as the stoichiometric reductants and the progress made in the use of late transition metals for the same reactions using silanes, stannanes and borohydrides as the reductant. The mechanisms for the reactions are discussed along with stereoselective variants of the reactions. [Pg.216]

All of the reactions described above use anionic alkyl metal complexes as stoichiometric reductants. Cationic zirconium catalyst 58 was shown to re-ductively cyclize a variety of 1,5-dienes to give both mono- and bicyclic silane products when H3SiPh was employed as the stoichiometric reductant (Scheme 10) [32]. Poor yields due to competing polymerization processes were observed when less substituted dienes were employed. It is likely that... [Pg.227]

See Dichlorodi-/r-chlorobis(pentamcthylcyclopentadienyl)dirhodium Air, Alkyl-metals... [Pg.458]

The mechanisms of the hydroxycarbonylation and methoxycarbonylation reactions are closely related and both mechanisms can be discussed in parallel (see Section 9.3.6).631 This last reaction has been extensively studied. Two possibilities have been proposed. The first starts the cycle with a hydrido-metal complex.670 In this cycle, an alkene inserts into a Pd—H bond, and then migratory insertion of CO into an alkyl-metal bond produces an acyl-metal complex. Alcoholysis of the acyl-metal species reproduces the palladium hydride and yields the ester. In the second mechanism the crucial intermediate is a carbalkoxymetal complex. Here, the insertion of the alkene into a Pd—C bond of the carbalkoxymetal species is followed by alcoholysis to produce the ester and the alkoxymetal complex. The insertion of CO into the alkoxymetal species reproduces the carbalkoxymetal complex.630 Both proposed cycles have been depicted in Scheme 11. [Pg.192]

In the general context of donor/acceptor formulation, the carbonyl derivatives (especially ketones) are utilized as electron acceptors in a wide variety of reactions such as additions with Grignard reagents, alkyl metals, enolates (aldol condensation), hydroxide (Cannizzaro reaction), alkoxides (Meerwein-Pondorff-Verley reduction), thiolates, phenolates, etc. reduction to alcohols with lithium aluminum hydride, sodium borohydride, trialkyltin hydrides, etc. and cyloadditions with electron-rich olefins (Paterno-Buchi reaction), acetylenes, and dienes.46... [Pg.212]

Transformation of an alkyl metal species via a-H elimination to the (C, H)-chelating ground state (written as (b) of the scheme)... [Pg.209]

Reductive coupling leading to the alkyl metal state... [Pg.209]

However, the important new feature of metal alkylidenes (4.51) is metal-carbon pi-bonding. As discussed in Section 2.8, pi bonds between transition metals and main-group elements are of d -p type, much stronger than corresponding p —pn bonds between heavier main-group elements. Compared with simple metal hydrides and alkyls, metal-carbon pi-bonding in metal alkylidenes affects the selection of metal d orbitals available for hybridization and skeletal bond formation, somewhat altering molecular shapes. [Pg.400]

The existence of tr-complex intermediates in C-H activation chemistry has been suggested to explain inverse kinetic isotope effects in reductive elimination processes whereby alkanes are formed from alkyl metal hydrides (Scheme 3).9... [Pg.102]

By far the most important redox reaction relative to chemical stability is the reaction between an oxidizable material and oxygen from air. The particle size and any droplets have a large effect on the combustion properties. Some substances react so rapidly in air that ignition occurs spontaneously. These so called pyrophoric compounds (white phosphorus, alkali metals, metal hydrides, some metal catalysts, and fully alkylated metals and nonmetals) must be stored in the absence of air. [Pg.49]

Partially or fully alkylated metal hydrides Butyllithium, diethylaluminum hydride, triethylbismuth, trimethylaluminum... [Pg.55]

Asymmetric reduction of ketones or aldehydes to chiral alcohols has received considerable attention. Methods to accomplish this include catalytic asymmetric hydrogenation, hydrosilylation, enzymatic reduction, reductions with biomimetic model systems, and chirally modified metal hydride and alkyl metal reagents. This chapter will be concerned with chiral aluminum-containing reducing re-... [Pg.232]

It turns out that the insertion of a next molecule of propene in the branched alkyl metal complex is much slower than the insertion of propene in a regular chain formed after a 1,2 insertion. In several catalysts studied this leads to a situation in which a great deal of the catalyst sites are "dormant", i.e. the metal is tied up in unreactive secondary alkyl metal complexes. If eventually an... [Pg.214]

There is ample evidence that the reductive elimination of alkanes (and the reverse) is a not single-step process, but involves a o-alkane complex as the intermediate. Thus, looking at the kinetics, reductive elimination and oxidative addition do not correspond to the elementary steps. These terms were introduced at a point in time when o-alkane complexes were unknown, and therefore new terms have been introduced by Jones to describe the mechanism and the kinetics of the reaction [5], The reaction of the o-alkane complex to the hydride-alkyl metal complex is called reductive cleavage and its reverse is called oxidative coupling. The second part of the scheme involves the association of alkane and metal and the dissociation of the o-alkane complex to unsaturated metal and free alkane. The intermediacy of o-alkane complexes can be seen for instance from the intramolecular exchange of isotopes in D-M-CH3 to the more stable H-M-CH2D prior to loss of CH3D. [Pg.392]


See other pages where Alkylated metals is mentioned: [Pg.536]    [Pg.557]    [Pg.37]    [Pg.112]    [Pg.145]    [Pg.39]    [Pg.41]    [Pg.105]    [Pg.152]    [Pg.656]    [Pg.1070]    [Pg.19]    [Pg.210]    [Pg.455]    [Pg.29]    [Pg.304]    [Pg.276]    [Pg.180]    [Pg.922]    [Pg.123]    [Pg.215]    [Pg.393]    [Pg.43]    [Pg.315]   
See also in sourсe #XX -- [ Pg.188 ]




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Aldehydes with metal alkyls

Alkali Metal Salts of O-Alkyl Alkylphosphonic Acids IIA-IIE

Alkali metal alkyls

Alkali metal fluorides alkyl halides

Alkali metals alkyl halides

Alkali metals alkyl migration

Alkenes insertions into metal-alkyl bonds

Alkyl Derivatives of the Group II Metals

Alkyl Derivatives of the Group II Metals B. J. Wakefield

Alkyl Hydroperoxides, Peroxyl Acids, and Metal Peroxides

Alkyl and Aryl Derivatives of Transition Metals

Alkyl and Metal Halide Compounds

Alkyl and aryl metal amide

Alkyl and aryl metal compound

Alkyl block metal

Alkyl bromides transition-metal-catalyzed

Alkyl complexes metal hydroxides

Alkyl fluorides dissolving metals

Alkyl fluorides metal-ammonia

Alkyl halides 1.1- allyl metals

Alkyl halides 1.1- propargyl metals

Alkyl halides metal enolates

Alkyl halides sodium metal

Alkyl halides with alkali metals

Alkyl halides with metal cations

Alkyl halides with metal hydrides

Alkyl halides with transition metal reagents

Alkyl homolytic-transition metal bond

Alkyl hydroperoxide-metal catalyst systems

Alkyl hydroperoxides reaction with transition metals

Alkyl metal halides

Alkyl metal hydroxide

Alkyl metal nitrosyls

Alkyl metals, 1-silyl-1-selenoreactions with carbonyl compounds

Alkyl metals, a-selenocarbonyl compound homologation

Alkyl metals, a-selenocarbonyl compound homologation functionalized

Alkyl metals, a-selenocarbonyl compound homologation reactions

Alkyl metals, a-selenocarbonyl compound homologation reactions with carbonyl compounds

Alkyl metals, a-selenocarbonyl compound homologation reactions with enals

Alkyl metals, a-selenocarbonyl compound homologation reactions with enones

Alkyl metals, a-selenocarbonyl compound homologation regiochemistry

Alkyl metals, a-selenocarbonyl compound homologation synthesis

Alkyl metals, a-selenocarbonyl compound homologation via metallation of selenides

Alkyl metals, a-selenoxyreactions with carbonyl compounds

Alkyl metals, vinyl halide cross-coupling

Alkyl phosphites, transition metal

Alkyl phosphites, transition metal complexes

Alkyl rare-earth metal complexes

Alkyl-metal compounds

Alkyl-metal porphyrin anion

Alkyl/amido alkali-metal magnesiates

Alkylammonium metal alkyl

Alkylation 1,3-diketone metal complexes

Alkylation acetylacetone metal complexes

Alkylation catalysts sulfated metal oxides

Alkylation catalysts supported metal halides

Alkylation complexes with metals

Alkylation metal-free

Alkylation of Nitro Compounds Using Transition Metal Catalysis

Alkylation with transition metal catalysts

Alkylations of metal enolates

Alkylations transition metal-catalyzed allylic

Alkyls of B subgroup metals

Allylic alkylation transition-metal catalyzed

Anionic polymerization alkali metal alkyls

Aryl and Metal-Alkyl Systems

Atomic metal alkyl

Bonding in metal alkyls

Bonding transition-metal alkyls

Borane complexes metal-alkyl

Boron Alkyls and Metal Alkyl Initiators of Free-Radical Polymerizations

Boron and metal alkyl initiators of free-radical polymerizations

Bridged (Associated) Metal Alkyls

Bridged species metal alkyls

By Reaction with Metals and Alkylating Agents

CO insertion into early transition metal alkyls

CO insertion into late transition metal alkyls

Carbon into metal alkyls

Carbon monoxide insertions metal-alkyl complexes

Carbon-metal bonds aryl, alkyl, and benzyl halides

Cationic alkyl rare-earth metal complexes

Cationic metal carbonyls alkylation

Characterization and Properties of Metal Alkyls

Charge Transfer alkyl metals

Chiral metal complexes alkylation

Chromates, metal alkyl

Chromates, metal alkyl alcohols

Chromates, metal alkyl catalytic oxidants

Complex alkyl-metal anions

Coupling, metal mediated, alkyl

Coupling, metal mediated, alkyl halides

Cyanides, metal, reaction with alkyl halides

Dipole moments transition metal alkyls

Dissolving metal conjugate reduction a-alkylated ketones

D° metal-alkyl complex

Elimination from metal alkyl complexes

Friedel-Crafts alkylation metal catalysis

From Metal Alkyls

From alkyl halides and bismuth metal

From metal cyanides alkylation

Group Metal Alkyls

HOMOGENEOUS DECOMPOSITION OF METAL ALKYLS AND ARYLS

Halides, alkyl reaction with metals

Halides, aryl, arylation metal catalyzed alkylation

Heterogeneous Polymerization Catalysts Derived from Transition Metal Alkyl Compounds

Homogeneous catalysts metal alkyl-free

Hydride transfer from transition metal alkyls

Initiators) metal alkyl

Insertion reactions metal alkyl

Intermediate metal alkyl

Ketones with metal alkyls

Lappert, Wilkinson and the Isolation of Stable Metal Alkyls und Aryls

Lithium, alkyl-: addn. to 1-alkenyl silanes halogen-metal exchange with

Magnetic properties transition metal alkyls

Main group-transition metal cluster alkylation

Merging Asymmetric Metal and Organocatalysis in Friedel-Crafts Alkylations

Metal Alkyls Aryls, and Hydrides

Metal alkyl bond dissociation energies

Metal alkyl clusters

Metal alkyl hydrides

Metal alkyl solutions

Metal alkyl, transition states leading

Metal alkyls

Metal alkyls Friedel-Crafts reaction

Metal alkyls Wurtz reaction and

Metal alkyls alkylcobalt complexes

Metal alkyls and aryls

Metal alkyls bond energies

Metal alkyls bridged

Metal alkyls carbonation

Metal alkyls catalysts

Metal alkyls diethyl zinc

Metal alkyls dimethylmercury

Metal alkyls elimination

Metal alkyls protonation

Metal alkyls storage

Metal alkyls tetraethyllead

Metal alkyls thermal dissociation

Metal alkyls thermolysis

Metal alkyls toxicity

Metal alkyls triethylaluminum

Metal alkyls triethylsilane

Metal alkyls triisobutylaluminum

Metal alkyls trimethylaluminum

Metal alkyls, nucleophilic reactivity

Metal alkyls, stable homoleptic

Metal aryloxides mixed alkyl

Metal atoms alkyl halides

Metal diastereoselective alkylation

Metal dienolates alkylation

Metal enolate alkylation

Metal enolates alkylation

Metal enolates alkylations

Metal enolates competition with C-alkylation

Metal groups alkyl halides

Metal halide, nucleophilic alkylation

Metal hydrides alkyl halides

Metal hydrides and alkyls

Metal phosphites reaction with alkyl halides

Metal-alkyl Lewis base interaction

Metal-alkyl Subject

Metal-alkyl bonds

Metal-alkyl bridge structures

Metal-alkyl complexes

Metal-alkyl complexes Agostic

Metal-alkyl complexes Bridging

Metal-alkyl complexes Electrophilic abstraction

Metal-alkyl complexes Metallacycles

Metal-alkyl complexes Preparation

Metal-alkyl complexes Stability

Metal-alkyl halide complexes

Metal-alkyl mechanism

Metal-alkyl polymer bonds, number

Metal-alkyl radical combination reactions

Metal-alkyl-free catalysts

Metal-free Alkylations by Acyl Halides on Polymeric Supports

Metal-mediated Schmidt Reactions of Alkyl Azides with Alkenes and Alkynes

Metalation 9-alkylated calix arenes

Metalation alkyl halides

Metallated chiral asymmetric alkylation

Metallation of -Dichloroethene and Subsequent Alkylation with Bromohexane

Metallation of Alkylarenes and Alkyl-hetarenes

Metallic alkyl compounds

Metals, activated reactivity with alkyl halides

Metals, activated with alkyl halides

Metals, forming associated alkyls

Migratory CO Insertion Reactions of Metal Alkyls

Miscellaneous Metal Alkyls

Nucleophilic allylation, alkali-metal alkyl

Olefins elimination from transition metal alkyls

Olefins metal alkyls

Organometallic compounds metal alkyls

Organometallic compounds, 1,4-addition with alkyl-metal bonds

Other Metal Compounds with Bridging Alkyl Groups

Other Metal-alkyl Complexes in the Environment

Oxidative addition, zinc metal alkyl bromides

Phosphines, alkylation from metal catalyzed

Phosphines, alkylation metal catalyzed addition

Phosphines, alkylation metal catalyzed arylation

Polymerization styrene, alkali-metal alkyl

Radical metal alkyl decomposition

Reaction of Alkyl, Alkenyl, and Aryl Halides with Metals

Reactions diamagnetic metal alkyl complexes with

Reactions of Transition Metal Compounds with Alkylating or Arylating Reagents

Reactions of metal alkyls

Rearrangement, 1,2-alkyl alkenes, metal catalyzed

Reducing agent metal alkyls

Reductive alkylation with other metals

Reductive alkylations metal-ammonia reduction

Regioselectivity transition-metal catalyzed allylic alkylations

Replacement in Transition Metal Alkyl Compounds and Polymerization Activity

Safety and handling of metal alkyl

Selected Reactions of Metal-Alkyl Complexes

Selenides reactions with alkyl metals

Sodium alkyl thiolates, reaction with halogen substituted metal complexes

Stability metal alkyls

Stability of transition metal alkyls

Stereoregular Polymerization with Transition Metal Alkyls

Stoichiometric reactions of isocyanides with metal alkyls

Structural Aspects of Alkyl and Aryl Metal Amides

Structural aspects of the metal alkyls

Structural studies transition metal alkyls

Structure and Bonding in Metal Alkyls

Synthesis from metal alkyls/hydrides

Synthesis of Metal-Alkyl Complexes

The Metal Alkyl — Lewis Base Interaction

The Metal-alkyl

The Preparation of Metal Alkyls

The Stability of Transition Metal Alkyls and Aryls

The properties of perfluoro-alkyl and -aryl transition metal complexes

Transfer with metal-alkyl

Transition Metal Alkyl and Alkenyl Complexes

Transition Metal-Catalyzed Alkylative Ring-Opening

Transition metal alkyl chemistry

Transition metal alkyl compounds

Transition metal alkyl compounds activity

Transition metal alkyl compounds heterogeneous polymerization catalysts

Transition metal alkyl compounds stereoregular polymerizations with

Transition metal alkyl compounds synthesis

Transition metal alkyls

Transition metal alkyls and aryls

Transition metal alkyls hydride transfer

Transition metal complexes alkyl

Transition metal complexes alkylation

Transition metal complexes, alkylations

Transition metal-alkyl bonds

Transition metal-catalyzed reactions allylic alkylations

Transition metals catalytic allylic alkylations

Transition metals, alkyl halide complexes

Transition-metal Alkyl and Related Catalysts

Transition-metal alkyl ions

Transition-metal organic compounds, alkyl

Transition-metal organic compounds, alkyl groups

Types of Metal Alkyls Investigated

Water alkyl halide-metal reaction

Ziegler-Natta catalysts metal alkyls

Zinc alkyls metal hydrides

Zwitterionic metal alkyl species

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