C₂-Symmetric Bissulfoxides as Organocatalysts in the Allylation of Benzoyl Hydrazones:  Spacer and Concentration Effects

Abstract

A comparative study on the allylation of a benzoyl hydrazone with allyl trichlorosilane using monosulfoxides, methylene-bridged C2-symmetric bissulfoxides, and ethylene-bridged C2-symmetric bissulfoxides shows that the enantioselectivity of the process is highly dependent on the spacer between the two sulfinyl sulfurs and the concentration of the reaction.

Catalytic asymmetric oxidation of sulfides to sulfoxides using (R)-6,6$$^{\prime }$$-Diphenyl-BINOL as a chiral ligand

“…Enantiopure sulfoxides have been widely used as chiral auxiliaries in a broad range of synthetic reactions like carbon-carbon 1,2 and carbon-oxygen 3 bond-forming reactions, cycloaddition reactions, [4][5][6] radical addition reactions 7,8 and in asymmetric catalysis. 9 Enantiopure sulfoxides have also found use in the pharmaceutical industry due to their important biological activity, for example, gastric acid proton pump inhibitor like Esomeprazole. 10 Other biologically active compounds containing the sulfinyl moiety include modafinil and sulindac, which have been used to treat narcolepsy and inflammation respectively.…”

Baker's‐Yeast‐Mediated Reduction of Sulfur‐Containing Compounds

“…Optically pure sulfoxides have attracted a great deal of interest in the past three decades due to their use as chiral auxiliaries in a broad range of synthetic reactions, including carbon–carbon104,105 and carbon–oxygen53 bond‐forming reactions, cycloaddition reactions106–108 and radical addition reactions,109,110 as well as in asymmetric catalysis 111. Furthermore, chiral sulfoxides are formed as metabolites of many sulfur‐containing drugs,112,113 and exhibit differential stereochemically dependent metabolism114,115 and enzyme inhibition 116…”

Recent Developments in Flavin‐Based Catalysis

“…The latter represents an advantage for the preparation of optically active compounds. Optically active sulfoxides have also been employed as catalysts in enantioselective organocatalytic processes [4].…”