Premium
Michael Additions of Methylene Active Compounds to Chalcone in Ionic Liquids without any Catalyst: The Peculiar Properties of Ionic Liquids
Author(s) -
Mečiarová Mária,
Toma Štefan
Publication year - 2007
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.200600870
Subject(s) - ionic liquid , dichloromethane , catalysis , chemistry , ionic bonding , chalcone , piperidine , reagent , organic chemistry , methylene , michael reaction , inorganic chemistry , solvent , ion
Michael additions of malonodinitrile as well as several other reagents to chalcone have been found to proceed well in pure ionic liquids, without the addition of any catalyst. The catalytic effect of the residual acidity caused by hydrolysis of ionic liquids anions was excluded because HCl in dichloromethane did not catalyse the Michael addition of malonodinitrile. Piperidine was tested as the catalyst and was found to be a much better catalyst in ionic liquids than in dichloromethane. Therefore, the following question arose: what is the effect of ionic liquids on the dissociation constants of CH acids?