A combined theoretical and experimental investigation on the enantioselective oxidation of aryl benzyl sulfides in the presence of a chiral titanium catalyst.
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 pi 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 pi interactions that drive the reaction along the observed stereochemical path is given.
Naso
Francesco
F
Dipartimento di Chimica and CNR ICCOM, Università di Bari via Orabon 4, 70125 Bari, Italy.
Capozzi
Maria Annunziata M
MA
Bottoni
Andrea
A
Calvaresi
Matteo
M
Bertolasi
Valerio
V
Capitelli
Francesco
F
Cardellicchio
Cosimo
C
D001593:Benzyl Compounds / Q000737:chemistry*; D002384:Catalysis; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D010084:Oxidation-Reduction; D013237:Stereoisomerism; D013816:Thermodynamics; D014025:Titanium / Q000737:chemistry*; D020122:tert-Butylhydroperoxide / Q000737:chemistry*
D001593:Benzyl Compounds; D020122:tert-Butylhydroperoxide; D014025:Titanium; C016367:benzyl sulfide