Asymmetric oxidation of sulfenates to sulfinates as a new route to optically active ortho-phosphorylated phenyl sulfoxides

Diastereoselective oxidation of menthyl arenesulfenates to sulfinates and access to enantioenriched aryl methyl sulfoxides

“…All these oxidations performed smoothly and led to good conversions, but took an unexpected long time when performed with the oxaziridine (up to 15 days). As previously stated, oxidation with NBS/H2O couple did not favor the same diastereomer as when performing the oxidation with mCPBA (Hamel et al 2005). For the three sulfinate esters 2, the observed diastereomeric excess was in the range 10-48%, so slightly lower than those obtained with ortho-phosphorylated menthyl benzenesulfinate (Hamel et al 2005).…”

“…To demonstrate the potential of the sequence we described earlier (Hamel et al 2005), it has been extended to other substrates. Thus, aryl methyl sulfoxides where the aromatic ring is functionalized with either a nitro (in ortho or para position) or an ortho-methoxycarbonyl groups were prepared following this strategy.…”

“…The synthesis of methyl thiosalicylate was performed according to a published procedure (yield 83%; lit. 97% as the crude material (Hamel et al 2005)).…”

“…For example, enantiopure sulfoxides have found many applications in chiral induction (Fernández and Khiar 2003), asymmetric catalysis (Pellissier 2006;Han et al 2018), and drug design, with the well-known Esomeprazole or its derivatives (Cotton et al 2000;Bentley 2005;O'Mahony et al 2011). Some years ago, we developed an innovative access to enantiopure ortho-phosphorylated phenylsulfoxides, by using as the key step an asymmetric oxidation of sulfenates to sulfinates (Hamel et al 2005;Abrunhosa et al 2005). ortho-Phosphorylated phenylsulfinate esters have been extensively studied by the groups of Drabowicz and Mikołajczyk, and such structures have found applications as mono-or bidentate ligands for the preparation of cisplatin derivatives (Laforgia et al 2004(Laforgia et al , 2005Mauger et al 2000;Hamel et al 2013).…”

Modern Stereoselective Synthesis of Chiral Sulfinyl Compounds

“…Diastereoselective oxidation of benzenesulfenates bearing a phosphonate group at the ortho -position leading to the corresponding sulfinates was investigated by Vazeaux, Drabowicz, and their co-workers. 156 Starting sulfenates 27 were obtained in the reaction of chiral alcohols with sulfenyl chloride 26 (in turn prepared from thiol 25 , Scheme 17 ). Menthyl derivatives were oxidized with tested oxidants with high yield and variable diastereoselectivity (up to 76% de for NBS), and the direction of asymmetric induction could be changed if the appropriate enantiomer of chiral oxaziridine was applied.…”