title: Enantioselective Sulfoxidation Catalyzed by a Bisguanidinium Diphosphatobisperoxotungstate Ion Pair.
abstract: The first enantioselective tungstate-catalyzed oxidation reaction is presented. High enantioselectivities were achieved for a variety of drug-like phenyl and heterocyclic sulfides under mild conditions with H2 O2 , a cheap and environmentally friendly oxidant. Synthetic utility was demonstrated through the preparation of (S)-Lansoprazole, a commercial proton-pump inhibitor. The active ion-pair catalyst was identified to be bisguanidinium diphosphatobisperoxotungstate using Raman spectroscopy and computational studies.
authors.affiliation: Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore, Singapore.
authors.forename: Xinyi
authors.initials: X
authors.lastname: Ye
authors.affiliation: Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore, Singapore.
authors.forename: Adhitya Mangala Putra
authors.initials: AM
authors.lastname: Moeljadi
authors.affiliation: Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore, Singapore.
authors.forename: Kek Foo
authors.initials: KF
authors.lastname: Chin
authors.affiliation: Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore, Singapore.
authors.forename: Hajime
authors.initials: H
authors.lastname: Hirao
authors.affiliation: Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore, Singapore.
authors.forename: Lili
authors.initials: L
authors.lastname: Zong
authors.affiliation: Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore, Singapore. choonhong@ntu.edu.sg.
authors.forename: Choon-Hong
authors.initials: CH
authors.lastname: Tan
keywords: Raman spectroscopy; asymmetric sulfoxidation; bisguanidinium; ion-pair catalysis; lansoprazole