Pd-catalyzed Oxidative Cyclization Research Articles

Palladium-Catalyzed Aminosulfonylation of ortho-Iodoanilines with the Insertion of Sulfur Dioxide for the Synthesis of 3,4-Dihydro-benzothiadiazine 1,1-Dioxides.

A simple and efficient Pd-catalyzed oxidative cyclization system is developed for the chemo- and regioselective synthesis of 3,4-dihydro-benzothiadiazine 1,1-dioxides, which are formed through aminosulfonylation of ortho-iodoanilines with SO2. DABSO is utilized as the source of SO2, and the organic compound O2 acts as an oxidant. This direct C-S, S-N, and C-N functionalization is highly efficient, and broad functional group tolerance is observed, resulting in moderate to excellent yields of 3,4-dihydro-benzothiadiazine 1,1-dioxides. Furthermore, this method is amenable to gram-scale synthesis.

Bimetallic Catalyzed Synthesis of 2-Arylindoles

AbstractA bimetallic synthesis of 2-arylindoles from alcohols and anilines is described. The dehydrogenation or oxidation of a secondary alcohol was performed by Ni- or Mn-catalyzed reactions, respectively. The formed ketone was converted into an imine intermediate that was later cyclized to the corresponding 2-arylindole by a Pd-catalyzed oxidative cyclization. A series of 2-arylindoles were prepared without isolation of the intermediates generated. The compatibility of the catalysts was investigated, and the optimized protocol opens room for the integration of Earth-abundant metals and palladium complexes to improve the sustainability of the synthesis of N-heterocycles.

Formal synthesis of brivaracetam: A key to construct the pyrrolidone scaffold using Pd-catalyzed oxidative cyclization and ring-closing metathesis reaction

A short and efficient synthetic approach for brivaracetam has been accomplished via two different routes which utilize Pd-catalyzed oxidative cyclization and ring-closing metathesis (RCM) as the key reaction. These two routes are novel, simple, scalable and rely on (E)-pent-2-en-1-ol and valeraldehyde as a commercially available starting material to yield brivaracetam with good overall yield.

Palladium-Catalyzed Intermolecular Oxidative Cyclization of Allyltosylamides with AcOH: Assembly of 3-Pyrrolin-2-ones.

The first example of Pd-catalyzed oxidative cyclization of allyltosylamides with acetic acid is reported. This transformation involved C-N/C-C bond formation and provided 3-pyrrolin-2-ones in a one-pot manner with easy-operation, excellent atom economy and good yields. Mechanistic studies indicate that the reaction proceeds through intermolecular aminopalladation, migratory insertion, reinsertion and β-hydride elimination processes.

Palladium-Catalyzed Intermolecular Aerobic Annulation of o-Alkenylanilines and Alkynes for Quinoline Synthesis.

A new approach to construct 2,3-disubstituted quinolines is described via Pd-catalyzed oxidative cyclization of o-vinylanilines and alkynes with molecular oxygen. This transformation is supposed to undergo intermolecular amination of alkyne, insertion of the olefin, and oxidative cleavage of C-C bond sequence.

ChemInform Abstract: Pd‐Catalyzed C—H Activation/Oxidative Cyclization of Acetanilide with Norbornene: Concise Access to Functionalized Indolines.

An efficient Pd-catalyzed oxidative cyclization reaction for the synthesis of functionalized indolines by direct C–H activation of acetanilide has been developed. The norbornylpalladium species formed via direct ortho C–H activation of acetanilides is supposed to be a key intermediate in this transformation.

Pd-Catalyzed C-H activation/oxidative cyclization of acetanilide with norbornene: concise access to functionalized indolines.

An efficient Pd-catalyzed oxidative cyclization reaction for the synthesis of functionalized indolines by direct C-H activation of acetanilide has been developed. The norbornylpalladium species formed via direct ortho C-H activation of acetanilides is supposed to be a key intermediate in this transformation.

Pd-catalyzed double C–H bond activation of diaryl ketones for the synthesis of fluorenones

An efficient synthesis of fluorenones from diaryl ketones by Pd-catalyzed oxidative cyclization is described. A possible mechanism involving a carbonyl group assisted ortho-C-H activation and cyclometalation followed by a second C-H activation to form a six-membered palladacycle and reductive elimination is proposed.

Diastereoselective Pd-Catalyzed Oxidative Cyclization of Enynes

Diastereoselective Pd-Catalyzed Oxidative Cyclization of Enynes