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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.

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 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.

A one-pot synthesis of 2-aryl- and 2-vinylindoles based on a ruthenium-catalyzed hydroamination and a palladium-catalyzed intramolecular Heck reaction is reported. The ruthenium-catalyzed addition reaction was applied to terminal as well as internal alkynes. Intramolecular Heck reactions of the resulting 2-chloroanilino enamines were achieved using an in situ generated palladium complex derived from an N-heterocyclic carbene.

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 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.

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.

Two distinct economical catalysts for intramolecular hydroaminations of electronically unactivated alkenes with basic amines are described, which are based on (a) group 4 metal halides under basic reaction conditions or (b) Bronsted-acid organocatalysts.

[reaction: see text] Air-stable and easily accessible PinP(O)H enables highly efficient palladium-catalyzed Kumada cross-coupling reactions of aryl tosylates. The in situ generated catalyst proved applicable not only to electron-rich and electron-poor carbocyclic tosylates but also to heterocyclic tosylates, such as pyridine and quinoline derivatives. The results described herein constitute the first use of air-stable secondary phosphine oxides as preligands for transition-metal-catalyzed coupling reactions between organometallic species and tosylates.

A palladium complex derived from air-stable TADDOLP(O)H catalyzes efficiently Hiyama, Stille, Kumada and Suzuki cross-coupling reactions of aryl and vinyl chlorides.

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.