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Magnesiumorganische Verbindungen konnen in einer Vielzahl nutzlicher Transformationen eingesetzt werden, die auch fur industrielle Prozesse von Bedeutung sind. Jungere Arbeiten zur Synthese hochfunktionalisierter Grignard-Reagenzien eroffnen hierbei faszinierende neue Perspektiven fur die organische Synthesechemie. Insbesondere der Zusatz uberstochiometrischer Mengen Lithiumchlorid erlaubt die Herstellung magnesiumorganischer Verbindungen ausgehend von Haloarenen oder Arenen unter sehr milden Reaktionsbedingungen. Diese hochfunktionalisierten Grignard-Reagenzien konnen als Startmaterialien fur ubergangsmetallkatalysierte Kreuzkupplungsreaktionen dienen. Neuere Entwicklungen im Ligandendesign resultieren in hochaktiven Palladium- und Nickelkatalysatoren fur effiziente Umsetzungen von preiswerten Chloriden und Tosylaten oder anspruchsvollen Fluoriden. Als okonomisch attraktive Alternative weisen eisenkatalysierte Kupplungsreaktionen magnesiumorganischer Verbindungen enormes Potential fur weitere Entwicklungen auf. Organomagnesium reagents can be employed for a variety of useful transformations, which are also of relevance for industrial processes. Recent protocols for syntheses of highly functionalized Grignard reagents highlight fascinating new perspectives for organic synthesis. Particularly, the addition of superstoichiometric amounts of LiCl allowed for the preparation of organomagnesium compounds, employing haloarenes or arenes at very mild reaction conditions. These highly functionalized Grignard reagents can be used as starting materials for transition metal-catalyzed cross-coupling reactions. New developments in the ligand design resulted in highly active palladium and nickel catalysts for efficient transformations of inexpensive chlorides or tosylates, as well as challenging fluorides. Economically attractive iron-catalyzed coupling reactions of organomagnesium reagents bear great potential for further developments.

A palladium complex derived from a sterically hindered diaminochlorophosphine allowed for Suzuki-Miyaura cross-couplings of chloroarenes with ample scope and provided access to tetra-ortho-substituted bi(hetero)aryls.

Air-stable secondary diaminophosphine sulfide preligands enable challenging nickel-catalyzed cross-coupling reactions of electron-deficient as well as electron-rich fluoro(hetero)arenes as electrophiles.

Catalytic amounts of aromatic carboxylic acid MesCO2H enabled efficient ruthenium-catalyzed direct arylations in apolar solvents with unparalleled broad scope via a concerted deprotonation−metalation mechanism.

Catalytic amounts of economically attractive [RuCl3(H2O)n] allow for direct arylations via C–H bond functionalization with aryl bromides under phosphine ligand-free reaction conditions. Thereby, a variety of functionalized (hetero)aryl bromides, bearing either electron-withdrawing or electron-releasing substituents, can be employed for direct arylations of pyridine, oxazoline, pyrazole, or ketimine derivatives as pronucleophiles.

Catalytic amounts of [RuCl 3 (H 2 O) n ] allow for direct -arylations via C-H bond functionalization with aryl bromides, -bearing a variety of important functional groups.

Studies on the use of easily accessible heteroatom-substituted secondary phosphine oxides as preligands for cross-coupling reactions are described. These air-stable sterically hindered phosphine oxides allow for efficient palladium-catalyzed Suzuki- and nickel-cat- alyzed Kumada-coupling reactions using electronically deactivated aryl chlorides. In addi- tion, they enable nickel-catalyzed coupling reactions of magnesium organyls with aryl fluo- rides at ambient temperature, and ruthenium-catalyzed coupling reactions of aryl chlorides via C-H bond activation. Finally, the application of modular diamino phosphine chlorides as preligands for a variety of transition-metal-catalyzed C-C and C-N bond formation reactions employing electron-rich aryl chlorides is presented.

Two selectively successive I/Cu exchange reactions performed with (Nphyl)CuLi allow the functionalization of indoles in positions 2 and 3. The 2,3-diketones prepared by this method can readily be converted to tricyclic heterocycles by standard methods.