Bisguanidinium dinuclear oxodiperoxomolybdosulfate ion pair-catalyzed enantioselective sulfoxidation.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 27869124.
- Also identified by DOI 10.1038/ncomms13455 and PMC identifier 5121337.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Catalytic use of peroxomolybdate for asymmetric transformations has attracted increasing attention due to its catalytic properties and application in catalysis. Herein, we report chiral bisguanidinium dinuclear oxodiperoxomolybdosulfate [BG]<sup>2+</sup>[(μ-SO<sub>4</sub>)Mo<sub>2</sub>O<sub>2</sub>(μ-O<sub>2</sub>)<sub>2</sub>(O<sub>2</sub>)<sub>2</sub>]<sup>2-</sup> ion pair, as a catalyst for enantioselective sulfoxidation using aqueous H<sub>2</sub>O<sub>2</sub> as the terminal oxidant. The ion pair catalyst is isolatable, stable and useful for the oxidation of a range of dialkyl sulfides. The practical utility was illustrated using a gram-scale synthesis of armodafinil, a commercial drug, with the catalyst generated in situ from 0.25 mol% of bisguanidinium and 2.5 mol% of Na<sub>2</sub>MoO<sub>4</sub>·2H<sub>2</sub>O. Structural characterization of this ion pair catalyst has been successfully achieved using single-crystal X-ray crystallography.