Schiff bases derived from hydroxyaryl aldehydes: molecular and crystal structure, tautomerism, quinoid effect, coordination compounds

• Published in: Macedonian Journal of Chemistry and Chemical Engineering Vol. 29; no. 2; pp. 117 - 138
• Main Authors: Anita Blagus, Dominik Cinčić, Tomislav Friščić, Branko Kaitner, Vladimir Stilinović
• Format: Journal Article
• Language: English
• Published: Society of Chemists and Technologists of Macedonia 15-12-2010
• Subjects: quinoid effect; schiff base complexes; schiff bases; supramolecular interaction; tautomerism
• ISSN: 1857-5552; 1857-5625
• DOI: 10.20450/mjcce.2010.159

During the last 50 years a vast number of structural studies on Schiff bases derived from hydroxyaryl aldehydes and their coordination compounds have been undertaken. In this review we present a systematic and brief overview of the most important discoveries and achievements accomplished in this field. The occurrence of Schiff bases (and their complexes) derived from nine most commonly used hydroxyaryl aldehydes in the Cambridge Structural Database (CSD) has been investigated. Keto-enol tautomerism and intramolecular hydrogen bonding in salicylaldimines and naphthaldimines is discussed, with a comment of the most common errors in determining the correct tautomeric form. Also, the interrelationship of crystal packing and the substituents on the Schiff base is studied. Finally, we give a short overview of conformational differences between free Schiff bases and Schiff bases bonded to metal ions as well as some structural characteristics of Schiff base metal complexes.