Palladium(II)-catalyzed C(alkenyl)À H alkenylation enabled by a transient directing group (TDG) strategy is described. The dual catalytic process takes advantage of reversible condensation between an alkenyl aldehyde substrate and an amino acid TDG to facilitate coordination of the metal catalyst and subsequent C(alkenyl)À H activation by a tailored carboxylate base. The resulting palladacycle then engages an acceptor alkene, furnishing a 1,3-diene with high regio-and E/Z-selectivity. The reaction enables the synthesis of enantioenriched atropoisomeric 2-aryl-substituted 1,3dienes, which have seldom been examined in previous literature. Catalytically relevant alkenyl palladacycles were synthesized and characterized by X-ray crystallography, and the energy profiles of the C(alkenyl)À H activation step and the stereoinduction model were elucidated by density functional theory (DFT) calculations.

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The site-selective palladium-catalyzed threecomponent coupling of unactivated alkenyl carbonyl compounds, aryl-or alkenylboronic acids, and Nfluorobenzenesulfonimide is described herein. Tuning of the steric environment on the bidentate directing auxiliary enhances regioselectivity and facilitates challenging C(sp 3 )À F reductive elimination from a Pd IV intermediate to afford 1,2-carbofluorination products in moderate to good yields.

A catalytic 1,2‐oxyhalogenation method that converts non‐conjugated internal alkynes into tetrasubstituted alkenes with high regio‐ and stereoselectivity is described. Mechanistically, the reaction involves a PdII/PdIV catalytic cycle that begins with a directed oxypalladation step. The origin of regioselectivity is the preference for formation of a six‐membered palladacycle intermediate, which is facilitated by an N,N‐bidentate 2‐(pyridin‐2‐yl)isopropyl (PIP) amide directing group. Selectivity for C(alkenyl)−X versus −N (X=halide) reductive elimination from the PdIV center depends on the identity of the halide anion; bromide and iodide engage in C(alkenyl)−X formation, while intramolecular C(alkenyl)−N reductive elimination occurs with chloride to furnish a lactam product. DFT calculations shed light on the origins of this phenomenon.

Palladium(II)-catalyzed C(alkenyl)–H alkenylation enabled by a transient directing group (TDG) strategy is described. The dual catalytic process takes advantage of reversible condensation between an alkenyl aldehyde substrate and an amino acid TDG to facilitate coordination of the metal catalyst and subsequent C(alkenyl)–H activation by a tailored carboxylate base. The resulting palladacycle then engages an acceptor alkene, furnishing a 1,3-diene with high regio- and E/Z-selectivity. The reaction enables the synthesis of enantioenriched atropoisomeric 2-aryl-substituted 1,3-dienes, which have seldom been examined in previous literature. Catalytically relevant alkenyl palladacycles were synthesized and characterized by X-ray crystallography, and the energy profiles of the C(alkenyl)–H activation step and the stereoinduction model were elucidated by density functional theory (DFT) calculations.

A catalytic 1,2-oxyhalogenation method that converts non-conjugated internal alkynes into tetrasubstituted alkenes with high regio-and stereoselectivity is described. Mechanistically, the reaction involves a Pd II /Pd IV catalytic cycle that begins with a directed oxypalladation step. The origin of regioselectivity is the preference for formation of a six-membered palladacycle intermediate, which is facilitated by an N,N-bidentate 2-(pyridin-2-yl)isopropyl (PIP) amide directing group. Selectivity for C(alkenyl)À X versus À N (X = halide) reductive elimination from the Pd IV center depends on the identity of the halide anion; bromide and iodide engage in C(alkenyl)À X formation, while intramolecular C(alkenyl)À N reductive elimination occurs with chloride to furnish a lactam product. DFT calculations shed light on the origins of this phenomenon.

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Palladium(II)‐catalyzed C(alkenyl)−H alkenylation enabled by a transient directing group (TDG) strategy is described. The dual catalytic process takes advantage of reversible condensation between an alkenyl aldehyde substrate and an amino acid TDG to facilitate coordination of the metal catalyst and subsequent C(alkenyl)−H activation by a tailored carboxylate base. The resulting palladacycle then engages an acceptor alkene, furnishing a 1,3‐diene with high regio‐ and E/Z‐selectivity. The reaction enables the synthesis of enantioenriched atropoisomeric 2‐aryl‐substituted 1,3‐dienes, which have seldom been examined in previous literature. Catalytically relevant alkenyl palladacycles were synthesized and characterized by X‐ray crystallography, and the energy profiles of the C(alkenyl)−H activation step and the stereoinduction model were elucidated by density functional theory (DFT) calculations.