Borax as an Efficient Metal-Free Catalyst for Hetero-Michael Reactions in an Aqueous Medium
作者:Sahid Hussain、Saitanya K. Bharadwaj、Mihir K. Chaudhuri、Harjyoti Kalita
DOI:10.1002/ejoc.200600691
日期:2007.1
Borax, a naturally occurring material, very efficiently catalyzed the conjugate addition of thiols, dithiols and amines to α,β-unsaturated ketones, nitriles, amides, aldehydes and esters in an aqueousmedium to afford the corresponding Michael adducts in good yields at room temperature. Recycling of the catalyst and scaling up of the reactions are important attributes of this catalysis. The reactions
Abstract Potassium fluoride supported on aluminaefficientlycatalyzes Michael addition of aromatic and aliphatic thiols to a variety of conjugated alkenes such as α,β‐unsaturated carbonyl compounds, carboxylic esters, amides, nitriles and chalcones. The Michael adducts are produced in good to excellent yields and relatively in short times. The catalyst can be recycled for subsequent reactions without