Andrew Behrle - Stabilization of MIV = Ti, Zr, Hf, Ce, and Th using a selenium bis(phenolate) ligand

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      Publication Details (including relevant citation   information):

      Andrew C. Behrle  a, Jessica R. Levin b, Jee Eon   Kim b,   Jonathan M. Drewett a, Charles L.   Barnes a,   Eric J. Schelter b and  Justin R. Walensky *a
      aDepartment of   Chemistry, University of Missouri-Columbia, 601 S. College   Avenue, Columbia, MO 65211-7600, USA. E-mail: walenskyj@missouri.edu
      bP. Roy and   Diana T. Vagelos Laboratories, Department of Chemistry,   University of Pennsylvania, Philadelphia, Pennsylvania 19104,   USA

      DOI: 10.1039/C4DT01798F (Paper) Dalton   Trans., 2015, 44, 2693-2702

      Abstract:

      We report M(IV) M   = Ti, Zr, Hf, Ce, and Th, complexes of a selenium bis(phenolate)   ligand, 2,2′-selenobis(4,6-di-tert-butylphenol),   (H2ArOSeO),   1. Reaction of   Ti(NEt2)4  with two equivalents of 1 affords   Ti(ArOSeO)2,   2. Salt metathesis of   ZrCl4 and   HfCl4 with two equivalents of   Na2ArOSeO   produces   Zr(ArOSeO)2(THF),   3, and   Hf(ArOSeO)2(THF),   4, respectively. Protonolysis of   ThCl[N(SiMe3)2]3  with two equivalents of 1 yields   Th(ArOSeO)2(THF)2,   5. Salt metathesis of   Ce(OTf)3 and two equivalents of   Na2ArOSeO   produces   [Na(THF)3][Ce(ArOSeO)2],   which was oxidized in situ using 0.5   equivalents of I2 to yield the   diamagnetic Ce(IV) product,   Ce(ArOSeO)2(THF)2,   6. Addition of 2,2′-bipyridyl to   6 forms   Ce(ArOSeO)2(bipy),   6a. Each diamagnetic complex was characterized   using 1H,   13C, and 77Se   NMR and IR spectroscopy and the structures of   2–6a were established with X-ray   crystallography. Electrochemical measurements using cyclic   voltammetry on complexes 2, 5,   and 6 are also reported.

      Address (URL): http://pubs.rsc.org/en/content/articlehtml/2015/DT/C4DT01798F