Abstract
A chiral ruthenium catalyst was developed for the enantioselective sulfoxidation of the title compounds. The catalyst combines two elements of chirality, a chiral pybox ligand and a chiral bicylic lactam unit, to which the ligand is attached. The latter unit was shown to improve significantly the performance of the catalyst by exposing one of the two enantiotopic sulfur atoms to the active site via hydrogen-bond mediated coordination. Ten differently substituted substrates were converted into the respective sulfoxides in yields of 52-71% and with ≥90% ee. Hand-in-hand: Two spatially remote chiral entities act synergistically together in the Ru-catalyzed sulfoxidation reaction of the title compounds. Hydrogen bonds and π-π interactions are invoked to explain the preferential formation of a single stereoisomer in this reaction. High enantioselectivities (90-99% ee).
Original language | English |
---|---|
Pages (from-to) | 10310-10313 |
Number of pages | 4 |
Journal | Chemistry - A European Journal |
Volume | 21 |
Issue number | 29 |
DOIs | |
State | Published - 1 Jul 2015 |
Keywords
- asymmetric catalysis
- hydrogen bond
- oxidation
- ruthenium
- sulfur heterocycles