IrIII metallacycle rapidly and selectively catalyses the reduction of various esters, carboxylic acids, ketones, and aldehydes. The reactions proceed in high yields at room temperature by hydrosilylation followed by desilylation. Depending on the substrate, esters are reduced to alcohols or ethers and carboxylic acids to alcohols or aldehydes.
[(NHC)CuX] complexes: Synthesis, characterization and catalytic activities in reduction reactions and Click Chemistry. On the advantage of using well-defined catalytic systems
作者:Silvia Díez-González、Eduardo C. Escudero-Adán、Jordi Benet-Buchholz、Edwin D. Stevens、Alexandra M. Z. Slawin、Steven P. Nolan
DOI:10.1039/c0dt00218f
日期:——
These complexes were then applied to two distinct organic reactions: the hydrosilylation of ketones and the 1,3-dipolar cycloaddition of azides and alkynes. In both transformations, outstanding catalytic systems were found for preparing the corresponding products in excellent yields and short reaction times. Most remarkably, the screening of well-defined systems in the hydrosilylation reaction allowed
methyl cation bearing N,N′-chelated conjugated-bis-guanidinate (CBG) has been reported. Its use in the catalysis of the hydrosilylation of a wide array of carbonyls, alkenes, and alkynes has been investigated. In addition, its behavior in the catalysis of the chemoselective hydrosilylation of aldehydes in the presence of reducible functional groups has been examined.
Pd-catalyzed selective hydrosilylation of aryl ketones and aldehydes
作者:Pandurang V. Chouthaiwale、Varun Rawat、Arumugam Sudalai
DOI:10.1016/j.tetlet.2011.10.155
日期:2012.1
Pd salts in combination with triethylsilane as hydride source and DMF as solvent has been found to be excellent catalytic combination that selectively reduces aryl ketones and aldehydes under mild conditions to afford triethylsilyloxy compounds in excellent yields. Product selectivity to the respective benzyl alcohols can however be achieved when the reaction was performed in DMF/H2O (4:1) as solvent system. (C) 2011 Elsevier Ltd. All rights reserved.
Rhodium-Catalyzed, Efficient Deutero- and Tritiosilylation of Carbonyl Compounds from Hydrosilanes and Deuterium or Tritium
作者:Miguel Rubio、Jesús Campos、Ernesto Carmona
DOI:10.1021/ol202117t
日期:2011.10.7
A cationic rhodium compound which is an active catalyst for both the hydrogen isotope exchange in hydrosilanes and the hydrosilylation of carbonyl compounds permits, in a one-flask, two-step procedure, efficient deutero- and tritiosilylations using SiEt3H under D-2 (0.5 bar) or T-2, at low catalyst loadings (0.1-0.5 mol%).