This communication describes a new and highly practical Pd(II)-catalyzed method for the regio- chemoselective oxidative functionalization of arenes alkanes. Carbon-hydrogen bonds substrates that contain variety directing groups (e.g., pyridine, azobenzene, pyrazole, imine derivatives) are selectively transformed into esters, ethers, aryl-halides under mild conditions. The scope this reaction in terms substrate, group, oxidant is described, preliminary catalytic cycle proposed.

This communication describes a new palladium-catalyzed method for the oxygenation of unactivated sp3 C−H bonds. A wide variety alkane substrates containing readily available oxime and/or pyridine directing groups are oxidized with extremely high levels chemo-, regio-, and in some cases diastereoselectivity. The substrate scope these reactions is discussed, selectivities rationalized on basis requirements putative palladium alkyl intermediates.

This communication describes the development of a new Pd-catalyzed method for fluorination carbon−hydrogen bonds. A key step these transformations involves palladium-mediated carbon−fluorine couplinga much sought after, but previously unprecedented, transformation. These reactions were successfully achieved under oxidative conditions using electrophilic N-fluoropyridinium reagents. Microwave irradiation in presence catalytic palladium acetate served as optimal C−H bonds variety substituted...

This communication describes a new Pd-catalyzed reaction for the highly chemo- and regioselective oxidative cross-coupling of aromatic C−H bonds. transformation is proposed to proceed via two discrete activation steps whose selectivities are predominantly controlled by proximity ligand (first activation) or steric environment around arene bond (second activation). Furthermore, selectivity second can be tuning Pd center.

A highly efficient and regioselective Pd-catalyzed method for the oxidative coupling of arylpyridine derivatives is reported. Remarkably, reactions proceed at room temperature are compatible with diverse functionalities, including aryl halides thiophenes. Mechanistic studies suggest that these transformations via a previously unprecedented mechanism involving two different pyridine-directed C−H activation reactionsone PdII center one PdIV.

A modification of the Sonogoshira coupling reaction employing an amidine base and a substoichiometric amount water generates symmetrical unsymmetrical bisarylethynylenes in one pot through situ deprotection trimethylsilylethynylene-added intermediates.

This communication describes mechanistic studies of the Pd-catalyzed oxidative cross-coupling benzo[h]quinoline with simple arenes. Through a series experiments, including determination order reaction in various reagents, H/D exchange studies, kinetic isotope effect investigations, and evaluation electronic effects, we propose detailed mechanism for these reactions. Importantly, this explains key role benzoquinone transformations; addition, it provides insights that allow rational tuning...

This paper presents a detailed investigation of the factors controlling site selectivity in Pd-mediated oxidative coupling 1,3-disubstituted and 1,2,3-trisubstituted arenes (aryl−H) with cyclometalating substrates (L∼C−H). The influence both concentration steric/electronic properties quinone promoter are studied detail. In addition, effect modulation carboxylate ligand is discussed. Finally, we demonstrate that substitution for carbonate X-type leads to complete reversal many arene...

Conditions for the rapid hydrolysis of chloroform to carbon monoxide (CO) using heterogeneous CsOH·H2O are described. CO and (13)CO can be generated cleanly rapidly under mild conditions captured either in or ex situ palladium-catalyzed aminocarbonylation reactions. Utilizing only 1-3 equiv allows aryl, vinyl, benzyl halides with a wide variety primary secondary amines giving amide products good excellent yields.

Copper-catalyzed intermolecular carboamination of alkenes with α-halocarbonyls and amines is presented 42 examples. Electron rich, electron poor, internal styrenes, as well α-olefins, are functionalized aryl or aliphatic amines. Mechanistic investigations suggest the reaction proceeding through addition a carbon-centered radical across an olefin followed by oxidation to form 5-membered oxocarbenium intermediate subsequent nucleophilic ring opening forge C-N bond.

A Rh-catalyzed enantioselective hydroamination of allylamines using a chiral BIPHEP-type ligand is reported. Enantioenriched 1,2-diamines are formed in good yields and with excellent enantioselectivities. diverse array nucleophiles amine directing groups demonstrated, including deprotectable motifs. Finally, the methodology was demonstrated toward rapid synthesis 2-methyl-moclobemide.

The development of an anti-Markovnikov-selective hydroamination unactivated alkenes is a significant challenge in organometallic chemistry. Herein, we present the rhodium-catalyzed homoallylic amines. proximal Lewis basic amine serves to promote reactivity and enforce regioselectivity through formation favored metallacycle, thus over-riding inherent alkene. scope both nucleophiles amines that participate reaction demonstrated.

The synthesis of 1,2-diamines via a Rh-catalyzed intermolecular hydroamination N-allyl imines with cyclic amines is presented. Coordinating groups proximal to the olefin bind catalyst and promote transformation. reaction affords in very good yields functional-group-tolerant highly diastereoselective.

Nucleopalladation is one of the most common mechanisms for Pd-catalyzed hydro- and oxidative functionalization alkenes. Due to electronic bias π-alkene-palladium complexes, nucleopalladations with terminal aliphatic alkenes typically deliver nucleophile more substituted sp2 carbon form Markovnikov-selective products. The selective formation anti-Markovnikov nucleopalladation products requires inherent effects be overridden, which still a significant challenge reactions simple Because...

The regiodivergent Rh-catalyzed hydrothiolation of allyl amines and imines is presented. Bidentate phosphine ligands with larger natural bite angles (βn ≥ 99°), for example, DPEphos, dpph, or L1, promote a Markovnikov-selective in up to 88% yield >20:1 regioselectivity. Conversely, when smaller angle ≤ 86°), dppbz dppp, are employed, the anti-Markovnikov product formed 74% Initial mechanistic investigations performed consistent an oxidative addition/olefin insertion/reductive elimination...

The rhodium-catalyzed oxidative amidation of allylic alcohols and aldehydes is reported.

The copper-catalyzed hydroarylation of internal, unsymmeric alkynes is presented. Trisubstituted alkenes are obtained as single diastereomers in good to excellent yields and regioselectivities. scope the reaction presented with respect alkyne aryl iodide coupling partners. Initial mechanistic experiments indicate a hydrocupration event followed by two-electron oxidative addition/reductive elimination pathway.

Three-component carboamination of alkenes is significant interest due to the ease by which functionalized amines can be produced from readily available chemical building blocks. Previously, a variety carbon-centered radical precursors have been studied as carbon components for this reaction, however, use general alkyl sources has remained an unsolved challenge. Herein we present our efforts develop oxidative protocol that utilizes alkylboronic acids precursors. The presented work...

Herein, we report mechanistic investigations into the Cu-catalyzed three-component carboamination of alkenes with α-halo carbonyls and aryl amines via an oxocarbenium intermediate. Monitoring reaction reveals formation transient atom transfer radical addition (ATRA) intermediates both electron-neutral deficient vinyl arenes as well unactivated alkenes. Based on our experimental studies density functional theory calculations, is generated through subsequent intramolecular substitution....

Abstract Photoredox catalysis is a powerful means to generate odd-electron species under mild reaction conditions from wide array of radical precursors. Herein, we present the application this catalytic manifold address hydroalkylation and hydroaminoalkylation electronically diverse vinylarenes. This allows for generalized alkene leveraging common alkyl precursors, such as organotrifluoroborate salts carboxylic acids. Furthermore, utilizing easily accessible α-silyl amine reagents or...

Herein we report the three-component copper-catalyzed carboiminolactonization of α,β-unsaturated carbonyl derivatives. In presence a Cu(I) catalyst, α-haloesters, electron-deficient alkenes, and primary amines couple to generate γ-iminolactones in single step. The scope reaction is explored with respect three coupling partners. Nineteen examples are presented yields these hydrolytically labile heterocycles up 69%. Mechanistic investigations support formation an oxocarbenium by way atom...

Lasonolide A is a novel polyketide displaying potent anticancer activity across broad range of cancer cell lines. Here, an enantioselective convergent total synthesis the (-)-lasonolide in 16 longest linear and 34 steps described. This approach significantly reduces step count compared to other known syntheses. The synthetic strategy utilizes alkyne-bearing substrates as core building blocks highlighted by stitching together two similarly complex halves via key Ru-catalyzed alkene-alkyne...

The lasonolides are novel polyketides that have displayed remarkable biological activity in vitro against a variety of cancer cell lines. Herein we describe our first-generation approach to the formal synthesis lasonolide A. key findings from these studies ultimately allowed us go on and complete total convergent unites two highly complex fragments utilizing Ru-catalyzed alkene-alkyne coupling. This type coupling typically generates branched products; however, through detailed investigation,...