Palladium-Catalyzed Four-Component Cascade Reaction for the Synthesis of Highly Functionalized Acyclic <i>O</i>,<i>O</i>‑Acetals

A palladium-catalyzed four-component cascade reaction of carbon dioxide, amines, allenyl ethers, and aryl iodides has been developed for the first time. The novel reaction allows simultaneous construction of three different new bonds (C–N, C–O, and C–C) in a single step, affording an efficient method for the synthesis of a variety of highly functionalized acyclic <i>O</i>,<i>O</i>-acetals. Excellent chemo- and regioselectivity, wide substrate scope, and good functional group tolerance are features of the method

Copper-Catalyzed [4 + 1] Annulation between α‑Hydroxy Ketones and Nitriles: An Approach to Highly Substituted 3(2<i>H</i>)‑Furanones

A copper-catalyzed [4 + 1] annulation between α-hydroxy ketones and nitriles has been developed. The reaction provides a facile and efficient method for the construction of a wide range of highly substituted 3­(2<i>H</i>)-furanones, a class of important compounds known to be associated with several biological activities

Palladium-Catalyzed Oxidative C–N Bond Coupling Involving a Solvent-Controlled Regioselective Bromination Process

Stereoselective palladium-catalyzed oxidative C–N bond coupling reactions between aromatic amines and alkenes involving a solvent-controlled regioselective bromination process under 1 atm of oxygen atmosphere are disclosed, providing easy access to two different brominated enamines. The addition of hydrogen peroxide (30% aq) as a co-oxidant in the system is crucial for the dehydrogenative aminohalogenation under molecular oxygen (1 atm), and in such a case, the C–N bond coupling/electrophilic bromination reaction cascade is proposed. Furthermore, the different reaction media leads to a switched regioselectivity of the process

Base-Promoted Formal [4 + 3] Annulation between 2<i>-</i>Fluoro­phenyl­acetylenes and Ketones: A Route to Benzoxepines

The first base-promoted formal [4 + 3] annulation between 2-fluorophenyl­acetylenes and ketones has been disclosed. The reaction proceeds through a tandem α-vinylation of ketones followed by an intramolecular nucleophilic aromatic substitution (S_NAr) reaction of the <i>in situ</i> generated β,γ-unsaturated ketone intermediates, providing a straightforward access to a wide range of functionalized benzoxepines in moderate to high yields. The transition-metal-free methodology featured a wide substrate scope, the use of easily available starting materials, and a high functional group tolerance

Palladium-Catalyzed Synthesis of 1<i>H</i>‑Indenes and Phthalimides via Isocyanide Insertion

A new and versatile multicomponent domino strategy has been developed for the synthesis of a series of 1<i>H</i>-indene and phthalimide derivatives from simple and readily available starting materials. This process operating under mild conditions shows a broad substrate scope with moderate to excellent yields

Base-Promoted Formal [4 + 3] Annulation between 2<i>-</i>Fluoro­phenyl­acetylenes and Ketones: A Route to Benzoxepines

The first base-promoted formal [4 + 3] annulation between 2-fluorophenyl­acetylenes and ketones has been disclosed. The reaction proceeds through a tandem α-vinylation of ketones followed by an intramolecular nucleophilic aromatic substitution (S_NAr) reaction of the <i>in situ</i> generated β,γ-unsaturated ketone intermediates, providing a straightforward access to a wide range of functionalized benzoxepines in moderate to high yields. The transition-metal-free methodology featured a wide substrate scope, the use of easily available starting materials, and a high functional group tolerance

Pd-Catalyzed Highly Regio- and Stereoselective Formation of C–C Double Bonds: An Efficient Method for the Synthesis of Benzofuran‑, Dihydrobenzofuran‑, and Indoline-Containing Alkenes

A highly regio- and stereoselective C–C double bond formation reaction via Pd-catalyzed Heck-type cascade process with <i>N</i>-tosylhydrazones has been developed. Various <i>N</i>-tosylhydrazones derived from both ketones and aldehydes are found to be efficient substrates to provide di- and trisubstituted olefins with high regio- and stereoselectivity. Furthermore, this reaction has a good functional group tolerance and different benzofuran-, dihydrobenzofuran-, and indoline-containing alkene products were obtained with high selectivity

Palladium-Catalyzed Synthesis of 1<i>H</i>‑Indenes and Phthalimides via Isocyanide Insertion

A new and versatile multicomponent domino strategy has been developed for the synthesis of a series of 1<i>H</i>-indene and phthalimide derivatives from simple and readily available starting materials. This process operating under mild conditions shows a broad substrate scope with moderate to excellent yields