Chromium(III)-Catalyzed Addition of Water and Alcohol to α,β-Unsaturated Ketones for the Synthesis of β-Hydroxyl and β-Alkoxyl Ketones in Aqueous Media
An efficient chromium(III) chloride-catalyzed Michael-type reaction of water or alcohol with α,β-unsaturatedketones is developed. A variety of α,β-unsaturatedketones effectively reacted with either water or alcohols to give the corresponding β-hydroxyl ketones or β-alkoxyl ketones in modest to high yields with excellent compatibility to various functional groups. The approach was further utilized
The Aldol Reaction under High-Intensity Ultrasound: A Novel Approach to an Old Reaction
作者:Giancarlo Cravotto、Alberto Demetri、Gian Mario Nano、Giovanni Palmisano、Andrea Penoni、Silvia Tagliapietra
DOI:10.1002/ejoc.200300369
日期:2003.11
We have employed high-intensityultrasound (HIU) to reinvestigate the aldolreaction (AR) in water. A number of aldols that under usual conditions would undergo elimination were isolated in acceptable to good yields. Within 15−30 min, acetophenone reacted with non-enolizable aldehydes to afford the aldol exclusively, while under conventional conditions (stirring or heating under reflux) the same compounds
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