An efficient and selective bis(amidate)bis(amido) titanium precatalyst for the anti-Markovnikov hydroamination of alkynes is reported. Hydroamination of terminal and internal alkynes with primary alkylamines, arylamines, and hydrazines is promoted by 5-10 mol % of Ti catalyst. Various functional groups are tolerated including esters, protected alcohols, and imines. The in situ generated complex shows comparable catalytic activity, demonstrating its synthetic versatility for benchtop application. Applications of this catalyst for the synthesis of amino alcohols and a one-pot procedure for indole synthesis are described. A mechanistic proposal that invokes turnover-limiting protonolysis is presented to rationalize the observed regioselectivities.

Unprotected secondary amines are directly alkylated by C-H functionalization adjacent to nitrogen, thereby opening new routes toward the synthesis of α- and β-alkylated N-heterocycles. α-Alkylated piperidine, piperazine, and azepane products are prepared from heterocycles and alkenes in an atom-economic reaction with excellent regio- and diastereoselectivity. β-Alkylated N-heterocycles are synthesized via a scalable one-pot alkylation/cyclization procedure generating 3-methylated azetidines, pyrrolidines, and piperidines.

Transition‐metal‐catalyzed hydroamination of alkynes with primary amines is a reliable tool for the synthesis of imines and enamines. Intramolecular hydroamination has been successfully applied in the synthesis of biologically relevant compounds, but intermolecular hydroamination is less commonly employed in synthesis, due to the possible formation of multiple regioisomers. With catalyst control, regioselectivity can be defined. This microreview focuses on recent advances in intermolecular alkyne hydroamination with primary amines in the presence of transition‐metal catalysts that are regioselective for anti‐Markovnikov addition. To highlight their potential use in synthesis, some recently developed methodologies that use intermolecular hydroamination in a tandem sequential manner to generate interesting organic cores are also covered.

α-Fluoromethylarenes are common substructures in pharmaceuticals and agrochemicals, with the introduction of fluorine often resulting in improved biological activity and stability. Despite recent progress, synthetic routes to α-fluorinated diarylmethanes are still rare. Herein we describe the Pd-catalyzed Suzuki-Miyaura cross-coupling of α-fluorinated benzylic triflones with arylboronic acids affording structurally diverse α-fluorinated diarylmethanes. The ease of synthesis of fluorinated triflones as the key starting materials enables powerful late-stage transformations of known biologically active compounds into fluorinated analogs.

No abstract

The development of fluorinated sulfone derivatives as versatile electrophiles for Suzuki–Miyaura cross-coupling reactions is described. Introducing electron-withdrawing groups on the aryl ring of the sulfone facilitates the Pd-catalyzed activation of C–SO2 bonds. Cross-coupling reactions with fluorinated sulfone electrophiles are reported, leading to a variety of multiply arylated products in good yields. The reactivity of this unusual electrophile is benchmarked versus common electrophiles and its use in iterative cross-couplings for concise synthesis of biologically active molecules is described.

The preparation of a novel Au6 cluster bearing a bidentate mixed carbene–thiolate ligand is presented.

The Pd-catalyzed desulfonative cross-coupling reaction of benzylic sulfone derivatives with 1,3-oxazoles via a deprotonative pathway has been developed. Broad substrate scope for both sulfone and 1,3-oxazole partners is observed, affording a variety of 1,3-oxazole-containing triarylmethanes. Sulfone partners that are primary benzylic, secondary benzylic, and benzhydryl are all effective. Using this method, the straightforward synthesis of multiply arylated structures has been demonstrated.