A Combined Theoretical and Experimental Investigation on the Enantioselective Oxidation of Aryl Benzyl Sulfides in the Presence of a Chiral Titanium Catalyst

✍ Scribed by Francesco Naso; Maria Annunziata M. Capozzi; Andrea Bottoni; Matteo Calvaresi; Valerio Bertolasi; Francesco Capitelli; Cosimo Cardellicchio

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 608 KB
• Volume: 15
• Category: Article
• ISSN: 0947-6539
• DOI: 10.1002/chem.200902110

✦ Synopsis

Abstract

An experimental investigation of the enantioselective oxidation of aryl benzyl sulfides by tert‐butyl hydroperoxide in the presence of a titanium/hydrobenzoin catalyst has shown that these sulfides are ideal substrates for this catalytic system, with negligible interference by the substituents on the aryl groups. A reaction mechanism based on DFT computations has been proposed. The DFT MPWB1K functional was used in the theoretical investigation to account for weak hydrogen‐bonding and π interactions. The computed reaction profile explains the experimentally observed enantioselectivity, which is determined by the thermodynamics of the first phase of the reaction. A detailed discussion of the hydrogen‐bonding and π interactions that drive the reaction along the observed stereochemical path is given.