and kinetically competent catalysts for this transformation. The fleeting transmetalation intermediate has been successfully synthesized through an alternative synthetic organometallic pathway at lower temperature, allowing for in situ NMR study of the C–N bond reductive elimination step. This study addresses key factors governing the mechanism of the nickel-catalyzed Buchwald–Hartwig amination process
Efficient and selective hydrogenation of C–O bonds with a simple sodium formate catalyzed by nickel
作者:Xiaoxiang Xi、Tieqiao Chen、Ji-Shu Zhang、Li-Biao Han
DOI:10.1039/c7cc08709h
日期:——
A Ni-catalyzed hydrogenation of C–O compounds with sodium formate is developed. Various esters, i.e. aryl, alkenyl, benzyl pivalates, and even the arylethers, were efficiently reduced with a loading of nickel catalysts down to 0.5 mol%. Reactive functional groups such as C–C double bonds, carbonyl, CN, MeS and halogen groups are tolerable. This reaction can be used for the modification of complex
A nickel-catalyzed aryl thioether metathesis has been developed to access high-value thioethers. 1,2-Bis(dicyclohexylphosphino)ethane (dcype) is essential to promote this highly functional-group-tolerant reaction. Furthermore, synthetically challenging macrocycles could be obtained in good yield in an unusual example of ring-closingmetathesis that does not involve alkene bonds. In-depth organometallic
Ni-Catalyzed Stannylation of Aryl Esters via C−O Bond Cleavage
作者:Yiting Gu、Rúben Martín
DOI:10.1002/anie.201611720
日期:2017.3.13
Ni‐catalyzed stannylation of aryl esters with air‐ and moisture‐insensitive silylstannyl reagents via C −Ocleavage is described. This protocol is characterized by its wide scope, including challenging combinations, thus enabling access to versatile building blocks and orthogonal C−heteroatom bond formations.
Investigations on the catalytic carboxylation of olefins with CO<sub>2</sub> towards α,β-unsaturated carboxylic acid salts: characterization of intermediates and ligands as well as substrate effects
salts and a detailed investigation on the critical steps in the catalysis are reported. The influence of two chelating phosphine ligands and several olefins on the elemental steps of the catalysis is shown. The work focusses on the formation of intermediate olefin complexes, lactoneformation and base induced elimination of the lactone. The direct carboxylation of olefins is possible using nickel catalysts