China
Africa
Explore chapters and articles related to this topic
Organic Synthesis
Published in Suresh C. Ameta, Rakshit Ameta, Garima Ameta, Sonochemistry, 2018
Chetna Ameta, Arpit Kumar Pathak, P. B. Punjabi
The Knoevenagel condensation reaction is an organic reaction named after Emil Knoevenagel. It is a modification of the aldol condensation (Knoevenagel, 1898). A Knoevenagel condensation is a nucleophilic addition of an active hydrogen compound to a carbonyl group followed by a dehydration reaction, where a molecule of water is eliminated. The product is often an a,P-unsaturated ketone (a conjugated enone).
Chalconoid metal chelates: spectral, biological and catalytic applications
Published in Journal of Coordination Chemistry, 2019
Metal–chalcone bonding upon chelation serves both to influence the steric environment of the metal coordination sphere and to adapt the electronic properties of the metal. These strong interactions provide some control over the molecular geometry and reactivity of chalconoid metal chelates. Understanding of the chalcone influence on structure and reactivity when they are bound to the metal ions leads to new materials in the field of medicine. In addition, such an understanding allows chemists to understand reactive complexes of relevance, and to expose new modes of bonding between metal centers and chalcone scaffolds. The α,β-unsaturated ketone (enone) moiety is responsible for the biological performances and also is significant in defining the geometry of coordination complexes. The enone consists of two key functionalities, a carbon–oxygen double bond (carbonyl group) and carbon–carbon double bond adjacent to the carbonyl group. The heterodiene molecular functionalities form stable complexes with transition as well as non-transition elements, so we can expect more than one type of coordination when chalcones interact with the metal center.