Copper-Catalyzed Asymmetric Conjugate Addition of Trialkylaluminium Reagents to Trisubstituted Enones: Construction of Chiral Quaternary Centers
作者:Magali Vuagnoux-d'Augustin、Alexandre Alexakis
DOI:10.1002/chem.200701001
日期:2007.11.26
vinylalane species undergo enantioselective conjugateaddition to a wide range of 2- or 3-substituted enones (cyclopent-2-enones, cyclohex-2-enones, 3-methyl cyclohept-2-enone) in the presence of catalytic amount of copper salt (copper thiophene carboxylate, [Cu(CH3CN)4]BF4 or [CuOTf]2C6H6) and tropos-phosphoramidite-based ligand. Thus, chiral quaternarycenters can be built, with up to 98% ee after rigorous
Pt-Catalyzed Oxidative Rearrangement of Cyclic Tertiary Allylic Alcohols to Enones Using Aqueous Hydrogen Peroxide
作者:Takashi Nagamine、Yoshihiro Kon、Kazuhiko Sato
DOI:10.1246/cl.2012.744
日期:2012.7.5
An oxidative rearrangement of cyclic tertiary allylic alcohols to β-disubstituted α,β-unsaturated ketones by Pt black catalyst with aqueous hydrogen peroxide is described. The reaction proceeds under organic solvent- and halide-free conditions and gives only water as a coproduct. The Pt black catalyst is commercially available and can be reused at least four times.
Reversal of .pi.-facial diastereoselection upon electronegative substitution of the substrate and the reagent
作者:Andrzej S. Cieplak、Bradley D. Tait、Carl R. Johnson
DOI:10.1021/ja00204a018
日期:1989.10
Les reactions examinees incluent les additions d'alkyllithiums, les oxymercurations, les osmylations et les epoxydations pour des cyclohexanones et des methylenecyclohexanes substitues
Les 反应受试者影响 les 加成 d'烷基锂、les oxymercurations、les osmylations 和 les 环己酮和亚甲基环己烷替代物的环氧基化
Aerobic Oxidative Heck/Dehydrogenation Reactions of Cyclohexenones: Efficient Access to<i>meta</i>-Substituted Phenols
作者:Yusuke Izawa、Changwu Zheng、Shannon S. Stahl
DOI:10.1002/anie.201209457
日期:2013.3.25
catalyst, employing a 6,6′‐dimethyl‐2,2′‐bipyridine ligand, promotes both the aerobic oxidative Heck coupling and dehydrogenation reactions of cyclohexenones. These reactions may be combined in a one‐pot sequence to enable the straightforward synthesis of meta‐substituted phenols (see scheme).
Addition reaction of arylboronic acids to aldehydes and α,β-unsaturated carbonyl compounds catalyzed by conventional palladium complexes in the presence of chloroform
作者:Tetsuya Yamamoto、Michiko Iizuka、Hiroto Takenaka、Tetsuo Ohta、Yoshihiko Ito
DOI:10.1016/j.jorganchem.2008.12.032
日期:2009.4
Arylboronic acids react with aldehydes and α,β-unsaturatedcarbonylcompounds in the presence of a base and a catalytic amount of a palladium(0) complex with chloroform, affording the corresponding addition products in good yields, and chiral benzhydrol was obtained with up to 43% e.e. using (S,S)-bppm as a ligand. General palladium complexes have no catalytic activity without chloroform. Because chloroform