The hydration of α,β‐unsaturatedketones with water proceeded efficiently in the presence of In(OTf)3 (20 mol%) in aqueous media to afford synthetically versatile β‐hydroxyketones in moderate to good yields with good functional group compatibility. The method also can be extended to the hydroalkoxylation of α,β‐unsaturatedketones with various alcohols for the efficient synthesis of β‐alkoxyketones as
Abstract An efficient method was developed for the conjugate addition of water to various α,β-unsaturatedketones by using bismuth(III) chloride as a catalyst. The reactions proceeded smoothly in the presence of a catalytic amount of BiCl3 (20 mol%) in aqueous media to furnish a variety of synthetically useful β-hydroxyl ketones in moderate to good yields. Apart from water molecule, various alcohols
Photo-induced Polar Addition of Protic Solvents to Cycloalkenones. Evidence for the Ground-state<i>trans</i>Isomers as Chemically-reactive Intermediates
作者:Ryoji Noyori、Masao Katô
DOI:10.1246/bcsj.47.1460
日期:1974.6
The photo-induced reaction of cyclic α,β-unsaturated ketones with protic media is described. The irradiation of 2-cycloheptenone or 2-cyclooctenone in various protic solvents (alcohols, acetic acid, water, and diethylamine) results in the formation of Michael-type solvent adducts. The chemically-reactive species have been demonstrated to be the highly strained trans isomers in a ground state. The irradiation of cis-2-cyclononenone affords the stable trans isomer, which reacts in the dark with methyl alcohol at an elevated temperature to give 3-methoxycyclononanone. The irradiation of 2-cyclohexenone in methyl alcohol yields 3-methoxycyclohexanone in a poor yield. The possible existence of trans-2-cyclohexenone is discussed.
Asymmetric 1,4-reductions of and 1,4-additions to enoates and related systems
申请人:——
公开号:US20030125563A1
公开(公告)日:2003-07-03
One aspect of the present invention relates to methods for the transition-metal-catalyzed asymmetric 1,4-addition of a nucleophile, e.g., hydride, to cyclic and acyclic enoates and enones. In certain embodiments of the methods of the present invention, the transition metal catalyst consists essentially of copper and an asymmetric bidentate bisphosphine ligand.