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Six new naturally occurring diacetylenic spiroacetal enol ethers, Lactiflodiynes A–F (1–6), together with five known congeners (7–11), were isolated from the whole plant of Artemisia lactiflora (Compositae). The structures were elucidated by extensive spectroscopic methods, X-ray crystallography, chemical transformations, and CD. The absolute configuration of Lactiflodiyne A (1) was determined to be 2R, 5S, 6S, and 7R by an X-ray crystallographic diffraction experiment using Mo Kα radiation with the absolute parameter of 0.01(8). In combination with CD, the absolute configurations of compounds 2–11 were confirmed by chemical transformations using 1 as the starting material.

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.

A palladium-catalyzed reaction sequence consisting of an intermolecular amination and an intramolecular direct arylation enabled highly regioselective syntheses of functionalized indoles or carbazoles and proved to be amenable to the use of inexpensive 1,2-dichloroarenes as electrophiles.

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.

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

Catalytic amounts of phosphoric acid diesters enabled highly efficient intramolecular hydroaminations of nonactivated alkenes. With an enantiomerically enriched Bronsted acid catalyst an unprecedented metal-free asymmetric hydroamination of a nonactivated alkene was accomplished.

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.