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Metal mediated

Metal Ion-Promoted Reactions of Thiols. Metal ion-promoted reactions of thiols have been reviewed (53). The bulk of the coverage concerns metal ion promoted aspects of sulfur chemistry. The main topics of interest are the formation of sulfenamides, sulfides, and disulfides using metal-mediated reactions. [Pg.13]

To date a number of reactions have been carried out in ionic liquids [for examples, see Dell Anna et al. J Chem Soc, Chem Commun 434 2002 Nara, Harjani and Salunkhe Tetrahedron Lett 43 1127 2002 Semeril et al. J Chem Soc Chem Commun 146 2002 Buijsman, van Vuuren and Sterrenburg Org Lett 3 3785 2007]. These include Diels-Alder reactions, transition-metal mediated catalysis, e.g. Heck and Suzuki coupling reactions, and olefin metathesis reactions. An example of ionic liquid acceleration of reactions carried out on solid phase is given by Revell and Ganesan [Org Lett 4 3071 2002]. [Pg.77]

A unique method to generate the pyridine ring employed a transition metal-mediated 6-endo-dig cyclization of A-propargylamine derivative 120. The reaction proceeds in 5-12 h with yields of 22-74%. Gold (HI) salts are required to catalyze the reaction, but copper salts are sufficient with reactive ketones. A proposed reaction mechanism involves activation of the alkyne by transition metal complexation. This lowers the activation energy for the enamine addition to the alkyne that generates 121. The transition metal also behaves as a Lewis acid and facilitates formation of 120 from 118 and 119. Subsequent aromatization of 121 affords pyridine 122. [Pg.319]

Transition metal-mediated transformations of heterocycles 98MI26, 98MI27. [Pg.210]

Metal-mediated iodocarbocyclization and iodoaminocyclizaton reactions leading to heterocycles 99SL1191. [Pg.217]

Transition metal-mediated syntheses of carbazole derivatives 95MI6. [Pg.249]

As discussed in Section 7.3, conventional free radical polymerization is a widely used technique that is relatively easy to employ. However, it does have its limitations. It is often difficult to obtain predetermined polymer architectures with precise and narrow molecular weight distributions. Transition metal-mediated living radical polymerization is a recently developed method that has been developed to overcome these limitations [53, 54]. It permits the synthesis of polymers with varied architectures (for example, blocks, stars, and combs) and with predetermined end groups (e.g., rotaxanes, biomolecules, and dyes). [Pg.329]

The total synthesis of ( )-estrone [( )-1 ] by Vollhardt et al. is a novel extension of transition metal mediated alkyne cyclotrimeriza-tion technology. This remarkable total synthesis is achieved in only five steps from 2-methylcyclopentenone (19) in an overall yield of 22%. The most striking maneuver in this synthesis is, of course, the construction of tetracycle 13 from the comparatively simple diyne 16 by combining cobalt-mediated and ort/io-quinodimethane cycloaddition reactions. This achievement bodes well for future applications of this chemistry to the total synthesis of other natural products. [Pg.165]

Transition metal-mediated phosphorus-carbon bond cleavage and its relevance to homogeneous catalyst deactivation. P. E. Gorrou, Chem. Rev., 1985,85,171 (109). [Pg.68]

Cu-mediated Ullman reaction has been used for the polymerization of dihaloaryls. For example, see ref. 3. This type of polymerization as well as other transition-metal-mediated reactions that involve radicals in the polymerization process is not included in this chapter. [Pg.467]

Pyridones can also be converted to 2-chloropyridines by exchanging the carbonyl functionality using phosphoroxychloride (POCI3) [72]. A combination of N-halosuccinimides and triphenylphosphine has also been applied to introduce halogens in this position [73]. The carbonyl functionality in 2-pyridones makes these systems reactive towards nucleophiles as well, which add in 1,4-reactions with displacement of halides [74]. The use of transition metal mediated couplings like Heck, and Suzuki have also been successfully applied on halogenated 2-pyridones (d. Scheme 10) [36,75]. [Pg.17]

This chapter has taken the reader through a number of microwave-assisted methodologies to prepare and further functionalize 2-pyridone containing heterocycles. A survey of inter-, intramolecular-, and pericyclic reactions together with electrophilic, nucleophilic and transition metal mediated methodologies has been exemplified. Still, a number of methods remain to be advanced into microwave-assisted organic synthesis and we hope that the smorgasbord of reactions presented in this chapter will inspire to more successful research in this area. [Pg.27]

Abstract A literature overview, up to the end of 2004, of the most important microwave-assisted transition-metal-mediated processes used for the decoration and construction of heterocycles is presented. The emphasis of the chapter lies in the use of palladium-assisted reactions but examples of copper- and nickel-mediated processes are also incorporated. [Pg.155]

Keywords Copper MAOS (Microwave assisted organic synthesis) Nickel Palladium Transition-metal-mediated bond formation... [Pg.155]

It has recently been shown that the transition metal-mediated decoration of the pyrazinone scaffold can greatly benefit from microwave irradi-... [Pg.275]

M-substituted 2-pyridones can be prepared by N-alkylation, under basic conditions (pfCa of the amide proton is 11). The resulting anion can then react on either nitrogen or oxygen depending on the conditions employed [24-27]. Also, several direct methods for the construction of N-substituted 2-pyridones have been reported. Two such examples can be seen in Scheme 3 where the first example (a) is an intramolecular Dieckmann-type condensation [28] and the second (b) is a metal-mediated [2 -I- 2 + 2] reaction between alkynes with isocyanates [29,30]. [Pg.312]

Ehses M, Romerosa A, Peruzzini M (2002) Metal-Mediated Degradation and Reaggregation of White Phosphorus. 220 107-140... [Pg.233]

Metal-Mediated Degradation and Reaggregation of White Phosphorus... [Pg.285]

Delmonte AJ, Dowdy ED, Watson DJ (2004) Development of Transition Metal-Mediated Cyclopropanation Reaction. 6 97-122 Demonceau A, see Noels A (2004) 11 155-171 Derien S, see Dixneuf PH (2004) 11 1-44... [Pg.290]

Department of Metal-Mediated Synthesis Debye Research Institute Utrecht University Padualaan 8... [Pg.307]

Scheme 6 Chain propagation in transition-metal-mediated NCA polymerization... Scheme 6 Chain propagation in transition-metal-mediated NCA polymerization...

See other pages where Metal mediated is mentioned: [Pg.202]    [Pg.388]    [Pg.389]    [Pg.332]    [Pg.556]    [Pg.348]    [Pg.154]    [Pg.791]    [Pg.831]    [Pg.487]    [Pg.98]    [Pg.925]    [Pg.949]    [Pg.208]    [Pg.311]    [Pg.137]    [Pg.147]    [Pg.140]    [Pg.309]    [Pg.90]    [Pg.121]    [Pg.234]    [Pg.15]    [Pg.126]   
See also in sourсe #XX -- [ Pg.590 ]




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Addition reactions metal-mediated

Alcohol metal-mediated

Aldehydes metal-mediated reactions

Alkali-metal-mediated metalation

Alkaloids metal-mediated reactions

Alkenes, metal mediated

Alkynes, metal mediated

Alkynes, metal mediated acids

Alkynes, metal mediated metalation

Alkynes, metal mediated metathesis

Alkynes, metal mediated reaction with

Alkynes, metal mediated reactions

Alkynes, metal mediated reagents

Alkynes, metal mediated reduction

Alkynes, metal mediated reductive coupling

Alkynes, metal mediated trimerization

Allylation reaction metal-mediated

Allylic substitution metal-mediated reactions

Amide hydrolysis metal-mediated

Amides lithium-amide-mediated metalation

Antibiotics metal-mediated

Assemblies Mediated by External Metal Centers

Assemblies metal-mediated

Azomethine ylide generation, metal-mediated

Azomethine ylides metal-mediated reaction

Boronic acids, metal mediated

Boronic acids, metal mediated coupling

Boronic acids, metal mediated oxidation

Carbanion Transition Metal-Mediated

Carbon metal mediated

Carbon monoxide insertion, transition metal-mediated

Catalysis via Transition Metal-Mediated Carbene Transfer to Sulfides

Chemistry metal-mediated

Coupling, metal mediated, alkyl

Coupling, metal mediated, alkyl halides

Cyclization reactions metal-mediated/catalyzed

Cycloadditions Mediated by Coordination of the Substrate(s) around a Transition Metal

Electrophilic Transition-Metal-Mediated Aromatization Reactions

Halides, aryl, arylation metal mediated coupling

Heterocyclization, metal-mediated

Hydroboration metal-mediated process

Hydrogenation metal-mediated

IL-Supported or Mediated Metal Nanoparticles

Macrocyclization transition metal mediated

Metal Complex-Mediated Radical Polymerization

Metal Complex-mediated NO Disproportionation

Metal Ion Mediated Molecular Imprinting

Metal Oxide-Mediated Partial Oxidation

Metal Vinylidene Mediated Reactions

Metal catalysts, silver-mediated oxidation

Metal complex redox mediators

Metal inorganic oxide surface-mediated

Metal mediated ammonium salts

Metal mediated arylboronic acids

Metal mediated carbonylation

Metal mediated coupling

Metal mediated coupling unsymmetrical

Metal mediated coupling with alkynes

Metal mediated coupling with allylic halides

Metal mediated hydroxylation

Metal mediated oxidative decarboxylation

Metal mediated polymerizations

Metal mediated radical couplings

Metal mediated reaction with

Metal mediated reaction, thiols with

Metal mediated transesterification

Metal mediated, acylation

Metal mediated, acylation amines

Metal mediated, acylation carbonylation

Metal mediated, acylation halides

Metal mediated, acylation reaction

Metal mediated, acylation reagents

Metal oxide mediated oxidation

Metal oxides, membrane-mediated

Metal surface-mediated synthesis

Metal-Containing Enzyme-Mediating Complexes

Metal-Mediated Oxidation of Alcohols - Mechanism

Metal-Mediated Photochemistry

Metal-Mediated Synthesis of Allenes

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

Metal-mediated Schmidt reactions

Metal-mediated activation

Metal-mediated aldol and Reformatsky-type reactions

Metal-mediated and Catalysed Reactions

Metal-mediated bond cleavage reactions

Metal-mediated carbene transfer

Metal-mediated conjugate addition reactions

Metal-mediated coupling reactions

Metal-mediated cyclization

Metal-mediated cycloaddition

Metal-mediated domino

Metal-mediated neurodegenerative disease

Metal-mediated oxidation of alcohol

Metal-mediated oxidative polymerization

Metal-mediated peptide assembly

Metal-mediated reactions

Metal-mediated reactions irreversibility

Metal-mediated rearrangements

Metal-mediated rearrangements copper

Metal-mediated rearrangements rhodium

Metallic nanoparticles plant-mediated green synthesis

Non-transition Metal-Mediated Solid-Supported Reactions

Olefin metal-mediated enantioselective

Olefins metal-mediated reactions

Other Transition Metal-Mediated Processes

Oxidation metal-mediated

Peptides metal mediated

Pyridines metal-mediated transformations

Radical Reaction Mediated by Grignard Reagents in the Presence of Transition Metal Catalyst

Rare-earth metal-mediated bimetallic

Rare-earth metal-mediated bimetallic cleavage

Redox mediators organic metals

Redox-mediated metal deposition

Regioselectivity metal-mediated reactions

Related Cycloadditions Mediated by Other Transition Metals

Replacement of a halogen by transition metal mediated coupling

Self metal-mediated

Sparteine-mediated metalation

Stereoselectivity metal-mediated reactions

Substitution reactions metal-mediated

The First Examples of Transition Metal-Mediated 1,3-Dipole Formation

Transition Metal Mediated Homogeneous Reductive Amination

Transition Metal Mediated Processes

Transition Metal-Mediated Alkenylations, Arylations, and Alkynylations

Transition Metal-Mediated Aromatic Ring Construction

Transition Metal-Mediated C(l) Nucleophilic Reactivity

Transition Metal-Mediated Carbanion Equivalent Formations

Transition Metal-Mediated Cyclization

Transition metal mediated polymerization

Transition metal-mediated

Transition metal-mediated alkynylation

Transition metal-mediated approaches

Transition metal-mediated condensation

Transition metal-mediated condensation reactions

Transition metal-mediated coupling

Transition metal-mediated cross-coupling

Transition metal-mediated cycloadditions

Transition metal-mediated polycondensation

Transition metal-mediated reactions in organic synthesis

Transition metals as mediators of disease processes

Transition-Metal-Catalyzed and -Mediated Mechanisms

Transition-Metal-Mediated Aromatic Ring Construction, First Edition. Edited by Ken Tanaka

Transition-Metal-Mediated Oxidative Coupling

Transition-metal mediated nitrenoid transfer

Transition-metal-mediated cross-coupling reactions

Transition-metal-mediated heterocyclic synthesis

Transition-metal-mediated radical

Transition-metal-mediated radical polymerization

Transition-metal-mediated reactions

Ylide compounds metal-mediated reaction

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