Direct Acylation of Aryl Chlorides with Aldehydes by Palladium−Pyrrolidine Co-catalysis
摘要:
A palladium catalyst system has been developed that allows for the direct acylation of aryl chlorides with aldehydes. The choice of ligand, as well as the presence of pyrrolidine and molecular sieves is shown to be critical to the catalysis, which appears to proceed via an enamine intermediate. The reaction was successful for a wide range of aryl chlorides and tolerant of functionality on the aldehyde component, giving easy access to alkyl aryl ketones in modest to good yields.
Arylation of Aldehydes To Directly Form Ketones via Tandem Nickel Catalysis
作者:Chuanhu Lei、Daoyong Zhu、Vicente III Tiu Tangcueco、Jianrong Steve Zhou
DOI:10.1021/acs.orglett.9b01782
日期:2019.8.2
both aliphatic and aromatic aldehydes proceeds with air-stable (hetero)arylboronic acids, with an exceptionally wide substrate scope. The neutral condition tolerates acidic hydrogen and sensitive polar groups and also preserves α-stereocenters of some chiral aldehydes. Interestingly, this nickel(0) catalysis does not follow common 1,2-insertion of arylmetal species to aldehydes and β-hydrogen elimination
Chemoselective synthesis of ketones and ketimines by addition of organometallic reagents to secondary amides
作者:William S. Bechara、Guillaume Pelletier、André B. Charette
DOI:10.1038/nchem.1268
日期:2012.3
is of great importance, as this motif serves as a synthetic handle for the elaboration of numerous organic functionalities. In this context, we report a general and chemoselective method based on an activation/addition sequence on secondaryamides allowing the controlled isolation of structurally diverse ketones and ketimines. The generation of a highly electrophilic imidoyl triflate intermediate was
Palladium-Catalyzed Reactions of Arylindium Reagents Prepared Directly from Aryl Iodides and Indium Metal
作者:Vardan Papoian、Thomas Minehan
DOI:10.1021/jo801074g
日期:2008.9.19
Treatment of aryl iodides with indium metal in the presence of lithiumchloride leads to the formation of an organoindium reagent capable of participating in cross-coupling reactions under transition-metal catalysis. Combination with aryl halides in the presence of 5 mol % Cl2Pd(dppf) furnishes biaryl compounds in good yields; similarly, reaction with acyl halides or allylic acetates/carbonates in
Catalytic Cross-Coupling Reaction of Esters with Organoboron Compounds and Decarbonylative Reduction of Esters with HCOONH<sub>4</sub>: A New Route to Acyl Transition Metal Complexes through the Cleavage of Acyl−Oxygen Bonds in Esters
ketones. Acyl−alkyl coupling to dialkyl ketones is also achieved by the use of 9-alkyl-9-BBN in place of boronates. The Ru3(CO)12-catalyzed decarbonylative reduction of esters with ammonium formate (HCOONH4) leading to hydrocarbons is also described. No expected aldehydes are produced, and controlled experiments indicate that aldehydes are not intermediate for the transformation. A hydrosilane can also be
A cobalt-catalyzed addition of aryl- and alkenylboronic acids to aldehydes and phthalaldehyde to give the corresponding biarylketones and 3-aryl phthalides in good to excellent yields in one pot is described.