Ruthenium-Catalyzed Enantioselective Addition of Carboxylic Acids to Allenes
作者:Jiang-Lin Hu、Felix Bauer、Bernhard Breit
DOI:10.1021/acscatal.1c03306
日期:2021.10.1
A ruthenium-catalyzed synthetic method for branched allylic esters via addition of carboxylicacids to allenes is reported. Ligands were designed and prepared based on the Josiphos skeleton, with which the reaction achieved up to 95% yield and up to >99% enantiomeric excess. A deuterium labeling experiment was performed and a plausible mechanism was proposed. Enantiopure lactones of five- and six-membered
A new strategy for the transformation of terminalalkynes to branched allylic sulfones was developed. Using a Rh(I)/DPEphos/benzoic acid catalyst system, terminalalkynes react with sulfonyl hydrazides to produce branched allylic sulfones with good to excellent yields and selectivities in general.
Triethylborane induces allylic substrates (benzoates, phenyl ethers, benzyl ethers, but not halides) to undergo allylation of aldehydes in the presence of a catalytic amount of tetrakis(triphenylphosphine)palladium(0) The reaction proceeds via Umpolung of pi-allylpalladium. (C) 1999 Elsevier Science Ltd. All rights reserved.
Iridium-Catalyzed Kinetic Asymmetric Transformations of Racemic Allylic Benzoates
作者:Levi M. Stanley、Chen Bai、Mitsuhiro Ueda、John F. Hartwig
DOI:10.1021/ja103779e
日期:2010.7.7
Versatile methods for iridium-catalyzed, kinetic asymmetric substitution of racemic, branched allylic esters are reported. These reactions occur with a variety of aliphatic, aryl, and heteroaryl allylic benzoates to form the corresponding allylic substitution products in high yields (74-96%) with good to excellent enantioselectivity (84-98% ee) with a scope that encompasses a range of anionic carbon and heteroatom nucleophiles. These kinetic asymmetric processes occur with distinct stereochemical courses for racemic aliphatic and aromatic allylic benzoates, and the high reactivity of branched allylic benzoates enables enantioselective allylic substitutions that are slow or poorly selective with linear allylic electrophiles.
[EN] BENZENE DERIVATIVE<br/>[FR] DÉRIVÉ DE BENZÈNE<br/>[JA] ベンゼン誘導体