A base-free, recyclable approach for the conjugate addition of aliphaticnitro compounds to enones to give γ-nitro ketones is presented. Reactions are carried out in an ionic liquid with a basic anionic moiety, such as BmimNTf2, as the solvent, under mild conditions (25 °C for 24 h). The IL medium could be recycled several times without any appreciable loss of activity, after a simple extraction procedure
Michael Additions in Aqueous Media: “On-Water” and “In-Water” Processes from α-Nitro Ketones and Their Anions
作者:Giorgio Giorgi、Pilar López-Alvarado、Sonia Miranda、Jean Rodriguez、J. Carlos Menéndez
DOI:10.1002/ejoc.201201431
日期:2013.3
A variety of α,β-unsaturatedaldehydes and ketones gave very high-yielding Michael addition reactions with α-nitrocycloalkanones in water, at room temperature without added catalyst. These can be considered as one of the very few “on-water” Michael reactions known in the literature, because they took place in suspension or emulsion and at increased speed relative to the same transformations performed