Kraig Wheeler

Publications (42) View all

• Source

  Available from: Yongming Deng

  Article: Arylamine-Catalyzed Enamine Formation: Cooperative Catalysis with Arylamines and Acids.

  Yongming Deng, Lu Liu, Ryan G Sarkisian, Kraig Wheeler, Hong Wang, Zhenghu Xu
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  ABSTRACT: Powerful combination: Arylamines and metal Lewis acids are used as catalysts in the highly chemo- and enantioselective three-component inverse-electron-demand aza-Diels-Alder reaction of cyclic ketones with enones. The enantioselectivity is introduced by a simple chiral anion. Arylamines can also serve as effective enamine catalysts in combination with either a metal Lewis acid or a Brønsted acid.
  Angewandte Chemie International Edition 02/2013; · 13.45 Impact Factor
• Article: Synthesis of diversely 1,3,5-trisubstituted pyrazoles via 5-exo-dig cyclization.

  Dmitry A Borkin, Mirela Puscau, Alena Carlson, Agnes Solan, Kraig A Wheeler, Béla Török, Roman Dembinski
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  ABSTRACT: 5-Exo-dig cyclocondensation of alk-3-yn-1-ones with hydrazines, in the presence of montmorillonite K-10, provides an effective method with a high atom economy for the synthesis of diversely 1,3,5-trisubstituted pyrazoles. The microwave-accelerated reaction proceeds in the absence of solvent and leads to 5-benzyl substituted pyrazoles with good yields (72-91%). The regiochemistry of the process was confirmed by the X-ray crystallographic structure determination of 1-(2-fluorophenyl)-5-(4-methylbenzyl)-3-phenyl-1H-pyrazole.
  Organic & Biomolecular Chemistry 05/2012; 10(23):4505-8. · 3.70 Impact Factor
• Source

  Available from: Lu Liu

  Article: Asymmetric inverse-electron-demand hetero-Diels-Alder reaction of six-membered cyclic ketones: an enamine/metal Lewis acid bifunctional approach.

  Zhenghu Xu, Lu Liu, Kraig Wheeler, Hong Wang
  Angewandte Chemie International Edition 03/2011; 50(15):3484-8. · 13.45 Impact Factor
• Article: A three-component reaction based on a remote-group-directed dynamic kinetic aza-Michael addition: stereoselective synthesis of imidazolidin-4-ones.

  Zhenghu Xu, Tyler Buechler, Kraig Wheeler, Hong Wang
  Chemistry 02/2010; 16(10):2972-6. · 5.93 Impact Factor
• Article: Structural and Spectroscopic Characterization of Mer-[RhBr3(Me2pzH)3] (Me2pzH = 3, 5-Dimethylpyrazole); Interpreting the Results with Density Functional Theory Calculations

  Max M. Abrahams, Gregory W. Cushing, Zachary N. Pickett, William A. Howard, Kraig A. Wheeler
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  ABSTRACT: Abstract Mer-RhBr3(Me2pzH)3 (Me2pzH=3,5-dimethylpyrazole) (monoclinic, P21/n, a=8.3300 (5)Å, b=16.2889 (9) Å, c=15.9299 (11) Å, α=90°, β=100.217 (5)°, γ=90°; V=2,127.2 (2) Å3; Z=4) has been characterized by X-ray diffraction, 1H and 13C nuclear magnetic resonance spectroscopy, infrared spectroscopy, and electronic absorption spectroscopy, and modeled by density functional theory (DFT) and time-dependent density functional theory (TDDFT). Mer-RhBr3(Me2pzH)3 is an octahedral complex with a HOMO→LUMO transition at 486nm. The DFT and TDDFT calculations predicted mer-RhBr3(Me2pzH)3 to be an octahedral complex with a HOMO→LUMO transition at 540nm. Graphical Abstract Mer-RhBr3(Me2pzH)3 (Me2pzH=3,5-dimethylpyrazole) has been structurally characterized by single crystal X-ray diffraction, spectroscopically characterized, and modeled by Density Functional Theory and Time-Dependent Density Functional Theory. KeywordsRhodium-Dimethylpyrazole-Density functional theory-X-ray structure-Electronic absorption spectroscopy-Infrared spectroscopy
  Journal of Chemical Crystallography 04/2012; 40(7):583-590. · 0.57 Impact Factor