Organometallics, cross-coupling

Meyer S, Orben CM, Demeshko S, Dechert S, Meyer F. Synthesis and characterization of di- and tetracarbene iron(II) complexes with chelating N-heterocychc carbene ligands and their apphcation in aryl Grignard-alkyl halide cross-coupling. Organometallics. 2011 30 6692—6702. 

Zhou Y, Zhang WX, Xi Z (2012) 1,3-Butadienylzinctrimer formed via transmetallation from 1,4-dilithio-l,3-butadienes synthesis, structural characterization and application in negishi cross-coupling. Organometallics 31 5546-5550... 

Cross coupling of organometallics with organic halides catalyzed by non (ill). 

In summary, palladium-mediated reactions, especially cross-coupling reactions have found many applications in quinoline synthesis. It is noteworthy that due to the a and S activation for the C(2) and C(4) positions, even 2-chloro- and 4-chloro-quinolines are viable substrates for palladium-catalyzed reactions under standard conditions. With the advent of the palladium chemistry and more commercially available organometallic substrates, more palladium-mediated quinoline syntheses are to be added to the repertoire of quinoline chemistry. 

Knochel et al. described Pd-catalyzed Negishi cross-coupling reactions between zinc organometallics and aryl iodides in [BMMlM][Bp4]. Scheme 5.2-20 illustrates the reaction for the formation of a 3-substituted cyclohexenone from 3-iodo-2-cyclo-hexen-l-one [82]. 

Negishi E, Tan Z (2005) Diastereoselective, Enantioselective, and Regioselective Carbo-alumination Reactions Catalyzed by Zirconocene Derivatives. 8 139-176 Netherton M, Fu GC (2005)Pa]ladium-catalyzed Cross-Coupling Reactions of Unactivated Alkyl Electrophiles with Organometallic Compounds. 14 85-108 Nicolaou KC, King NP, He Y (1998) Ring-Closing Metathesis in the Synthesis of EpothUones and Polyether Natmal Products. 1 73-104 Nishiyama H (2004) Cyclopropanation with Ruthenium Catalysts. 11 81-92 Noels A, Demonceau A, Delaude L (2004) Ruthenium Promoted Catalysed Radical Processes toward Fine Chemistry. 11 155-171... 

Cross-coupling reactions resulting in C-C bond formation are normally classified according to the nature of the organometallic reagent and the organic electrophile. Scheme 6.4 summarises, broadly, the names and reaction partners of the most common of these transformations. 

These are called cross-coupling reactions and usually involve three basic steps oxidative addition, transmetallation, and reductive elimination. In the transmetallation step an organic group is transferred from the organometallic reagent to palladium. 

Scheme 8.10. Palladium-Catalyzed Cross Coupling of Organometallic Reagents with...

This method can extend Ni-catalyzed cross coupling to functionalized organometallic reagents. 

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