Now showing items 1-20 of 37

    • 1,2-Selective Hydrosilylation of Conjugated Dienes 

      Parker, Sarah Elizabeth (2014-06-06)
      Selective 1,2-hydrosilylation of 1,3-dienes is a challenging problem to solve for transition metal catalysis. Butadiene, specifically, would be a useful substrate because 3-butenylsilane products have promise as superior ...
    • Application of Palladium-Mediated 18F-Fluorination to PET Radiotracer Development: Overcoming Hurdles to Translation 

      Kamlet, Adam; Neumann, Constanze Nicole; Lee, Eunsung; Carlin, Stephen M.; Moseley, Christian K.; Stephenson, Nickeisha A; Hooker, Jacob M; Ritter, Tobias (Public Library of Science, 2013)
      New chemistry methods for the synthesis of radiolabeled small molecules have the potential to impact clinical positron emission tomography (PET) imaging, if they can be successfully translated. However, progression of ...
    • Bimetallic Palladium Catalysis: Direct Observation of Pd(III)–Pd(III) Intermediates 

      Powers, David C.; Geibel, Matthias A. L.; Klein, Johannes E. M. N.; Ritter, Tobias (American Chemical Society, 2009)
      \(PhI(OAc)_2\) is a common oxidant for Pd-catalyzed C−H bond functionalizations. Mechanistic hypotheses since the 1960s have suggested a Pd(II)/Pd(IV) mechanism. Here we present evidence for the relevance of bimetallic ...
    • Bimetallic Redox Synergy in Oxidative Palladium Catalysis 

      Powers, David Charles; Ritter, Tobias (American Chemical Society, 2012)
      Polynuclear transition metal complexes, which are embedded in the active sites of many metalloenzymes, are responsible for effecting a diverse array of oxidation reactions in nature. The range of chemical transformations ...
    • Carbon–Fluorine Bond Formation 

      Furuya, Takeru; Kuttruff, Christian A.; Ritter, Tobias (Current Drugs Ltd., 2008)
      We present a selection of carbon–fluorine bond formations that have been developed in the recent past. An overview of the most common fluorination reagents is followed by fluorination reactions organized by reactivity. We ...
    • Carbon–Fluorine Reductive Elimination from a High–Valent Palladium Fluoride 

      Furuya, Takeru; Ritter, Tobias (American Chemical Society, 2008)
      We have observed two high-valent arylpalladiumfluoride complexes that afford carbon−fluorine bond formation upon thermolysis.
    • Charge Transfer Directed Radical Substitution Enables para-Selective C–H Functionalization 

      Boursalian, Gregory B.; Ham, Won Seok; Mazzotti, Anthony R.; Ritter, Tobias (2016)
      Efficient C–H functionalization requires selectivity for specific C–H bonds. Progress has been made for directed aromatic substitution reactions to achieve ortho- and meta- selectivity, but a general strategy for para-selective ...
    • Concerted nucleophilic aromatic substitution with 19F− and 18F− 

      Neumann, Constanze N.; Hooker, Jacob M.; Ritter, Tobias (2016)
      Nucleophilic aromatic substitution (SNAr) is widely used by organic chemists to functionalize aromatic molecules, and it is the most commonly used method to generate arenes that contain a 18F for use in PET imaging.1 A ...
    • Connecting Binuclear Pd(III) and Mononuclear Pd(IV) Chemistry by Pd–Pd Bond Cleavage 

      Powers, David Charles; Lee, Eunsung; Ariafard, Alireza; Sanford, Melanie S.; Yates, Brian F.; Canty, Allan J.; Ritter, Tobias (American Chemical Society, 2012)
      Oxidation of binuclear Pd(II) complexes with PhICl\(_2\) or PhI(OAc)\(_2\) has previously been shown to afford binuclear Pd(III) complexes featuring a Pd–Pd bond. In contrast, oxidation of binuclear Pd(II) complexes with ...
    • Deoxyfluorination of Phenols 

      Tang, Pingping; Wang, Weike; Ritter, Tobias (American Chemical Society, 2011)
      An operationally simple ipso fluorination of phenols with a new deoxyfluorination reagent is presented.
    • A Dinuclear Palladium Catalyst for \(\alpha\)-Hydroxylation of Carbonyls with \(O_2\) 

      Chuang, Gary Jing; Wang, Weike; Lee, Eunsung; Ritter, Tobias (American Chemical Society, 2011)
      A chemo- and regioselective \(\alpha\)-hydroxylation reaction of carbonyl compounds with molecular oxygen as oxidant is reported. The hydroxylation reaction is catalyzed by a dinuclear Pd(II) complex, which functions as ...
    • A Fluoride-Derived Electrophilic Late-Stage Fluorination Reagent for PET Imaging 

      Lee, Eunsung; Kamlet, Adam Seth; Powers, David C.; Neumann, Constanze Nicole; Boursalian, Gregory Bagrad; Furuya, Takeru; Choi, Daniel C.; Hooker, Jacob M.; Ritter, Tobias (American Association for the Advancement of Science, 2011)
      The unnatural isotope fluorine-18 \((^{18}F)\) is used as a positron emitter in molecular imaging. Currently, many potentially useful \(^{18}F\)-labeled probe molecules are inaccessible for imaging because no fluorination ...
    • Introduction of Fluorine and Fluorine-Containing Functional Groups 

      Liang, Theresa; Neumann, Constanze Nicole; Ritter, Tobias (Wiley-VCH Verlag Berlin, 2013)
      Over the past decade, the most significant, conceptual advances in the field of fluorination were enabled most prominently by organo- and transition-metal catalysis. The most challenging transformation remains the formation ...
    • Iron-Catalyzed 1,4-Hydroboration of 1,3-Dienes 

      Wu, Jessica Y.; Moreau, Benoît; Ritter, Tobias (American Chemical Society, 2009)
      A chemo-, regio-, and stereoselective iron-catalyzed 1,4-hydroboration of dienes that affords γ-disubstituted allylboranes has been developed. 1,4-Hydroboration of 2-substituted dienes forms allylborane products with ...
    • Iron-Catalyzed Polymerization of Isoprene and Other 1,3-Dienes 

      Raynaud, Jean; Wu, Jessica Y.; Ritter, Tobias (Wiley Blackwell (John Wiley & Sons), 2012)
    • Late-Stage Deoxyfluorination of Alcohols with PhenoFluor 

      Sladojevich, Filippo; Arlow, Sophie I.; Tang, Pingping; Ritter, Tobias (American Chemical Society (ACS), 2013)
      An operationally simple protocol for the selective deoxyfluorination of structurally complex alcohols is presented. Several fluorinated derivatives of natural products and pharmaceuticals have been prepared to showcase the ...
    • Late-Stage Fluorination With 19F− and 18F− via Concerted Nucleophilic Aromatic Substitution 

      Neumann, Constanze N. (2016-09-09)
      The formation of C–F bonds has long been considered a challenging transformation and C–F bonds commonly had to be formed early on in a synthetic sequence towards complex organofluorides. Late-stage fluorination reactions ...
    • Late-Stage Fluorination with \(^{18}F\) 

      Kamlet, Adam Seth (2013-03-19)
      Positron emission tomography (PET) is a powerful, non-invasive in vivo imaging technique used for diagnostics and drug development. The synthesis of \(^{18}F\)-PET tracers is challenging due to the short half-life of the ...
    • Late-Stage Fluorination: From Fundamentals to Application 

      Campbell, Michael G.; Ritter, Tobias (American Chemical Society, 2014)
      In this brief account, we review work from our lab with a focus on late-stage introduction of fluorine and fluorinated functional groups into small molecules. We attempt to highlight practical developments, which we believe ...
    • Mechanism of C−F Reductive Elimination from Palladium(IV) Fluorides 

      Furuya, Takeru; Benitez, Diego; Tkatchouk, Ekaterina; Strom, Alexandra E.; Tang, Pingping; Goddard, William A.; Ritter, Tobias (American Chemical Society (ACS), 2010)
      The first systematic mechanism study of C−F reductive elimination from a transition metal complex is described. C−F bond formation from three different Pd(IV) fluoride complexes was mechanistically evaluated. The experimental ...