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Transition‐metal‐catalyzed coupling reactions that involve the direct functionalization of insert C−H bond represent one of the most efficient strategies for forming carbon‐carbon bonds. Herein, a palladium‐catalyzed intramolecular C−H bond arylation of triaryl phosphates is reported to access seven‐membered cyclic biarylphosphonate targets. The reaction is achieved via a unique eight‐membered palladacyclic intermediate and shows good functional group compatibility. Meanwhile, the product can be readily converted into other valuable phosphate compounds. [ABSTRACT FROM AUTHOR]

Herein, metal-free phosphonation of N-heterocycles with diphenylphosphine oxides, promoted by easily available 1,5-diazabicyclo[5,4,0]undec-5-ene (DBU) in dimethyl carbonate (DMC) as a green solvent under an air atmosphere, is presented. This simple method can accommodate 1,2,4-triazine-3,5(2H,4H)-diones, quinoxalin-2(1H)-ones, quinoxalines and pyrazinones with diverse substituted diphenylphosphine oxides, delivering distinctive monophosphonated N-heterocycles with a broad functional group tolerance, and the transformations are also viable for post-modification of bioactive and pharmaceutical molecules. In addition to the sustainable feature of being metal- and photocatalyst-free and utilization of ambient air as an oxidant, this method efficiently achieves the gram-scale transformation, and the product was isolated through extraction and filtration, rather than column chromatography. [ABSTRACT FROM AUTHOR]

Visible-light-facilitated phosphorus radical reactions have been developed as a powerful and sustainable tool for the synthesis of various organophosphorus compounds. In general, these reactions require stoichiometric amounts of oxidants, and reductants, bases, and radical initiators, leading to uneconomical and complicated processes. Progress has been made over the past few years toward using reactions that proceed under eco-benign and mild reaction conditions. Furthermore, these reactions have broad functional group tolerance, with some facile and economical pathways. Herein, we summarize the discoveries and achievements pertaining to C–P bond formation through a visible light photocatalysis procedure with high atom economy, made by our group and other research groups. It was established that greener and more environmentally friendly approaches do not require an additional oxidant or base. Moreover, we have designed and synthesized a new type of P-radical precursor, which can take part in reactions without the requirement for any additional bases, oxidants, and additives. This breakthrough, pertaining to novel visible-light-induced transformations, will be discussed and a plausible mechanism is proposed, based on corresponding experiments and the literature. [ABSTRACT FROM AUTHOR]

An efficient strategy for the synthesis of benzazole-phosphine ligand precursors via N -heterocyclic carbene catalyzed aerobic oxidative cyclization reaction has been performed. The reaction displays broad functional group tolerance and high atom economy, and the transformation has been further applied to benzazole-phosphine ligand synthesis. [ABSTRACT FROM AUTHOR]

This review describes new methods for the synthesis of chiral monophosphine ligands with menthyl phenylphosphinate as a chiral auxiliary through asymmetric Suzuki-Miyaura cross-coupling reactions and asymmetric C-H functionalization. The chiral menthyl phenylphosphinate as a chiral auxiliary is easy to prepare and the menthyl group can easily be transformed into other functional groups, with the chiral center synchronously remaining. These methodologies provide highly efficient and practical strategies for the synthesis of novel axially chiral biaryl monophosphine oxides and their corresponding phosphines. Meanwhile, these reactions are easy to handle and exhibit wide scope for substrates with excellent diastereomeric ratios. [ABSTRACT FROM AUTHOR]

A novel protocol for the preparation of various 3-alkylideneoxindoles viaa silver-catalyzed aromatic C–H functionalization has been developed. The process is simple, environmentally conscious, and avoids the use of abundant bases, oxidants, or other additives. [ABSTRACT FROM AUTHOR]

A noveloxyfluorination of olefin reactions has been developed.The reactions involve a metal-free and green catalytic system forthe synthesis of α-fluoroketones which is an important buildingblock for organic synthesis. Moreover, this reaction system exhibitsgreat functional group tolerance. [ABSTRACT FROM AUTHOR]

Abstract: A novel arylnitration of alkenes by nitration and C–H functionalization cascade process has been developed. This methodology provides an efficient way to construct a variety of nitro-containing oxindoles and dihydroquinolin-2(1H)-ones. In addition, the process exhibits significant functional group tolerance. Moreover, the use of inexpensive and readily available starting materials makes this practical and atom-economical approach particularly attractive. [Copyright &y& Elsevier]

A novel R2(O)P-directed Pd(II)-catalyzed C–H hydroxylation to synthesize various substituted 2′-phosphorylbiphenyl-2-ol compounds is described. Notably, the reaction operates under mild conditions and shows good functional group tolerance, high selectivity, and yield. [ABSTRACT FROM AUTHOR]

The first Pd(II)-catalyzed C–H addition to isatins by direct sp2/sp3C–H bond activation for the construction of 3-substituted-3-hydroxy-2-oxindoles is reported. The bidentate nitrogen ligands were found to promote this reaction. Specifically, the preliminary bioassay indicated that 3-(5-chlorobenzoxazole)-3-hydroxy-N-benzyl-2-oxindole (2w) is a new inhibitor of human kidney cancer and hepatocellular carcinoma cells. Moreover, this reaction system exhibits great functional group tolerance and requires no directing group, extra base, or additives. [ABSTRACT FROM AUTHOR]

A novel and inexpensive method of nontoxic, silver-salt-catalyzed carboazidation of arylacrylamides to afford corresponding azide oxindoles is reported. This reaction system exhibits great functional group tolerance. All products form a crucial skeleton for the synthesis of various indole alkaloids. [ABSTRACT FROM AUTHOR]

A novel metal-free oxidative carbonitration of alkenes (I) and (III) by a nitration and C-H functionalization cascade process is reported. [ABSTRACT FROM AUTHOR]