Al(Salen) Metal Complexes in Stereoselective Catalysis

• Published in: Molecules (Basel, Switzerland) Vol. 24; no. 9; p. 1716
• Main Authors: Gualandi, Andrea, Calogero, Francesco, Potenti, Simone, Cozzi, Pier Giorgio
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 02.05.2019; MDPI
• Subjects: Aldehydes; Aluminum; aluminum metal complexes; Aromatic compounds; Backbone; bifunctional catalysis; Catalysis; Chemistry; chiral ligand; Chromium; Diamines; Ethylenediamine; Imines; Lewis Acid; Ligands; Metal complexes; Metal ions; Metals; organic synthesis; Review; salen; stereoselective reactions; Stereoselectivity; Lewis Acid; bifunctional catalysis; chiral ligand; organic synthesis; salen; stereoselective reactions; catalysis; aluminum; aluminum metal complexes
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules24091716

Salen ligands are a class of Schiff bases simply obtained through condensation of two molecules of a hydroxyl-substituted aryl aldehyde with an achiral or chiral diamine. The prototype salen, or , '-bis(salicylidene)ethylenediamine has a long history, as it was first reported in 1889, and immediately, some of its metal complexes were also described. Now, the salen ligands are a class of N,N,O,O tetradentate Schiff bases capable of coordinating many metal ions. The geometry and the stereogenic group inserted in the diamine backbone or aryl aldehyde backbone have been utilized in the past to efficiently transmit chiral information in a variety of different reactions. In this review we will summarize the important and recent achievements obtained in stereocontrolled reactions in which Al(salen) metal complexes are employed. Several other reviews devoted to the general applications and synthesis of chromium and other metal salens have already been published.