Saegusa Oxidation of Enol Ethers at Extremely Low Pd-Catalyst Loadings under Ligand-free and Aqueous Conditions: Insight into the Pd(II)/Cu(II)-Catalyst System
作者:Quan Zhu、Yunsong Luo、Yongyan Guo、Yushun Zhang、Yunhai Tao
DOI:10.1021/acs.joc.0c02987
日期:2021.4.16
system of Saegusa oxidation, which converts enolethers to the corresponding enals with a number of diverse substrates at extremely low catalyst loadings (500 mol ppm) under ligand-free and aqueous conditions, is described. Its synthetic utility was demonstrated by large-scale applications of the catalyst system to important nature molecules. This work allows Saegusa oxidation to become a highly practical
Synthesis of α,β-unsaturated aldehydes and nitriles via cross-metathesis reactions using Grubbs’ catalysts
作者:Sandra M. Rountree、Sarah F.R. Taylor、Christopher Hardacre、M. Cristina Lagunas、Paul N. Davey
DOI:10.1016/j.apcata.2014.08.032
日期:2014.9
A series of α,β-unsaturated aldehydes and nitriles of significant interest in the fragrance industry have been prepared using Grubbs’ catalysts in cross-metathesis reactions of electron-deficient olefins (i.e., acrolein, crotonaldehyde, methacrolein, and acrylonitrile) with various 1-alkenes, including 1-decene, 1-octene, 1-hexene and 2-allyloxy-6-methylheptane. The latter is of particular interest
Stereoselective Alkylation of α,β-Unsaturated Imines via C−H Bond Activation
作者:Denise A. Colby、Robert G. Bergman、Jonathan A. Ellman
DOI:10.1021/ja0584931
日期:2006.5.1
alkylation of α,β-unsaturated imines via C−H activation followed by imine hydrolysis produces tri- and tetrasubstitutedα,β-unsaturated aldehydes. In the presence of a rhodium catalyst, α,β-unsaturated N-benzyl imines derived from methacrolein, crotonaldehyde, and tiglic aldehyde undergo directed C−H activation at the β-position and react with terminal alkenes and alkynes to form the tri- and tetrasubstituted
Conjugate addition of methyl groups of αβ-unsaturated aldehydes: use of Me<sub>5</sub>Cu<sub>3</sub>Li<sub>2</sub>
作者:Derrick L. J. Clive、Vittorio Farina、Pierre Beaulieu
DOI:10.1039/c39810000643
日期:——
Me5Cu3Li2 converts αβ-unsaturated aldehydes efficiently into β-methyl aldehydes and, unlike Me2CuLi, it usually gives a negligible amount of the 1,2-adduct even when a quaternary carbon is generated in the reaction.
β-Trimethylsilyl enol ethers 1 (Z) obtained from β-bromoenolethers 2 were condensed with aliphatic and aromatic aldehydes in the presence of a catalytic quantity of trimethylsilyl triflate leading to ethylenic aldehydes 3 (E) with good yields (79–90%).