The effect of nitrogen atoms in the enantioselective oxidation of aryl or heteroaryl benzyl sulfides

Abstract

Some aminophenyl benzyl sulfides or benzyl pyridyl sulfides were asymmetrically oxidized with tert-butyl hydroperoxide in the presence of a complex between titanium i-propoxide and (S, S)-hydrobenzoin, an oxidation system that works particularly well with a vast set of aryl benzyl sulfides. Notwithstanding the presence of nitrogen-containing moieties that, in principle, could interfere with the correct co-ordination of the sulfide to the metal center, satisfactory levels of enantioselectivity (up to 78%) were measured for this oxidation process.

GRAPHICAL ABSTRACT

Keywords:

• oxidation
• enantioselectivity
• titanium
• hydrobenzoin
• sulfide

Acknowledgements

The ChemAxon (http://www.chemaxon.com) software package is gratefully acknowledged.

Notes

^†Dedicated to the memory of Prof. Alessandro Degl'Innocenti (1950–2012)