Catalytic Asymmetric Synthesis of Esomeprazole by a Titanium Complex with a Hexa-aza-triphenolic Macrocycle Ligand

<div><p></p><p>An efficient synthesis of esomeprazole via catalytic asymmetric oxidation of 1<i>H</i>-benzimidazolyl pyridinylmethyl sulfide by a titanium complex with a hexa-aza-triphenolic macrocycle ligand is described. Esomeprazole was prepared with 99.6% <i>ee</i>, which meets the high requirement of the European Pharmacopeia on enantiomeric purity.</p> </div