David M. Eichhorn

Associate Dean, Fairmount College of Liberal Arts and Sciences,
Professor

Education

  • A.B., Harvard University, 1986
  • Ph.D., University of California at Berkeley, 1992
  • Post doctorate, Northwestern University, 1992-1996

Principal Research Interests

  •     Metalloenzyme Model Complexes
  •     Polypyrazolylborate Complexes
  •     Conductive and Magnetic Coordination Polymers

Research in the Eichhorn group is in the area of synthetic inorganic chemistry. Two current projects, described below, are (i) the synthesis of coordination polymers using a new class of polypyrazolylborate ligands with cyano substituents and (ii) modeling the active sites of sulfur-coordinated metalloenzymes. The research effort involves synthesis of ligands and metal complexes, characterization of the metal complexes by a variety of spectroscopic and other analytical techniques, and structural analysis of the products by X-ray crystallography.

Cyano-substituted Polypyrazolylborates
A new class of polypyrazolylborate ligands with cyano substituents (left) has been developed and is being studied as precursors to magnetic and conductive polymers. Right is shown the crystal structure of the copper complex of a cyano-substituted bispyrazolylborate ligand, Cu(BpPh,4-CN)2.

Thiolate-substituted Metal Complexes
A new method for synthesizing metal complexes with mixed N/S coordination has been developed which uses an air-stable disulfide reactant. For example, the first Ni(II) complex of a tetradentate N3S donor ligand was synthesized by this technique. Compounds are being studied as models for the active sites of thiolate-coordinated metalloenzymes.

Publications

Representative
  1. Senaratne, N.K.; Mwania, T.M.; Moore, C.E.; Eichhorn, D.M.; “Ni complexes of N2S ligands with amine/imine and amine/amide donors with relevance to the active site of Ni Superoxide Dismutase”; Inorg. Chim. Acta 2018, 476, 27-37.
  2. Kadel, L.R.; Kromer, J.R.; Moore, C.E.; Eichhorn, D.M.; “New trisubstituted cyanopyrazoles and cyanoscorpionates”; Polyhedron 2017,125, 206-218.
  3. Kadel, L.R.; Bullinger, J.C.; Baum, Robert R.; Moore, C.E.; Tierney, D.L.; Eichhorn, D.M.; “Cyanoscorpionate Ligands: Agostic Interactions in a Series of Metal Complexes Containing the Tris(4-cyano-3-phenylpyrazolyl)borate and Bis(4-cyano-3-phenylpyrazolyl)borate Ligands”; Eur. J. Inorg. Chem. 2016 2543-2551.
  4. Sullivan, M.T.; Senaratne, N.R.; Eichhorn, D.M.; “Synthesis and X-ray Crystallographic Characterization of [In(tsalen)(OAc)] (tsalen = N,N'-Ethylenebis(thiosalicylideneimine))”; Polyhedron 2016, 114, 152-155
  5. Panja, A.; Eichhorn, D.M.; “A linear S-bridged trinuclear cobalt(III) complex with 2-amino-benzenethiol: synthesis, crystal structure, and spectroscopic characterization”; J. Coord. Chem. 2013, 66,  3037-3044.
  6. Panja, A.; Eichhorn, D.M.; “Mono- and di-nuclear nickel(II) complexes with mixed N/S-donor ligands: Syntheses, structures and physical properties”; Inorg. Chim. Acta 2012, 391, 88-92.
  7. Zimmerman, J.R.; Smucker, B.W.; Dain, R.P.; VanStipdonk, M.J.; Eichhorn, D.M.; “Tridentate N2S ligand from 2,2’-dithiodibenzaldehyde and N,N-dimethylethylenediamine: Synthesis, structure, and characterization of a Ni(II) complex with relevance to Ni Superoxide Dismutase”; Inorg. Chim. Acta 2011,373 54-61.
See All

47. Zimmerman, J.R.; Smucker, B.W.; Dain, R.P.; VanStipdonk, M.J.; Eichhorn, D.M.; “Tridentate N2S ligand from 2,2’-dithiodibenzaldehyde and N,N-dimethylethylenediamine: Synthesis, structure, and characterization of a Ni(II) complex with relevance to Ni Superoxide Dismutase”; Inorg. Chim. Acta 2011,373 54-61. DOI 10.1016/j.ica.2011.03.052

46. Andra, K.K.; Bullinger, J.C.; Bann, J.G.; Eichhorn, D.M.; 2-Fluoro-L-Histidine; Acta Cryst. 2010, E66, o2713. DOI 10.1107/S1600536810038663

45. Dou, D.; He, G.; Lai, Z.; Wei, L.; Alliston, K.R.; Lushington, G.H.; Eichhorn, D.M.; Groutas, W.C.; “Utilization of the 1,2,3,5-thiatriazolidin-3-one 1,1-Dioxide Scaffold in the Design of Potential Inhibitors of Human Leukocyte Proteinase 3“; Bioorg. Med. Chem. 2010, 18, 1093-1102. DOI 10.1016/j.bmc.2009.12.057

44. Eichhorn, D.M.; “Analysis of ‘Janus Scorpionates: Supramolecular Tectons for the Directed Assembly of Hard–Soft Alkali Metallopolymer Chains’ and ‘A Second-Generation Janus Scorpionate Ligand: Controlling Coordination Modes in Iron(II) Complexes’”; Chemtracts Organic Chemistry 2009, 22, 135-140.

43. Bullinger, J.C.; Eichhorn, D.M.; “Cyanoscorpionates: Co(II), Mn(II), and Ni(II) Complexes Coordinated Only Through the Cyano Group”; Inorg. Chim. Acta, 2009, 362, 4510-4516. DOI 10.1016/j.ica.2009.05.012

42. Panja, A.; Eichhorn, D.M.; “Synthesis and Characterization of Tetrahedrally and Octahedrally Coordinated Mixed Valence Cobalt(II,III) Complex with Thiosemicarbazone Based Ligand”; J. Coord. Chem. 2009, 62, 2600-2609. DOI 10.1080/00958970902915574

41. Dou, D.; Talaty, E.R.; Moore, C.; Bullinger, J.; Eichhorn, D.M.; Groutas, W.C.; “Formation of an Unusual Dimeric Product in the Reaction of a 1,2,5 –Thiadiazolidine 1,1 Dioxide-Derived Thioether with Sulfuryl Chloride”; J. Heterocyclic Chem. 2009, 46, 669 – 673. DOI 10.1002/jhet.136

40. Burns, D.H.; Meece, F.A.; Moore, C.E.; Eichhorn, D.M. “Two similar dibenzo cyclic ethers with dissimilar conformations”; Acta Crystallogr. 2009, C65, o27-o30.

39. Panja, A.; Campana, C.; Leavitt, C.; Van Stipdonk, M.J.; Eichhorn, D.M. “Iron and Cobalt Complexes of 2,6-Diacetylpyridine-bis(R-thiosemicarbazone) (R=H, phenyl) Showing Unprecedented Ligand Deviation from Planarity”; Inorg. Chim. Acta 2009, 362, 1348-1354.

38. Zhao, N.; Bullinger, J.C.; Van Stipdonk, M.J.; Stern, C.L.; Eichhorn, D.M.; “Cyanoscorpionates – Synthesis and Crystallographic Characterization of 1-D Cu(I) Coordination Polymers”; Inorg. Chem. 2008, 47, 5945-5950. DOI: 10.1021/ic8003307

37. Zhao, N.; Van Stipdonk, M.J.; Bauer, C.; Campana, C.; Eichhorn, D.M. “Sandwich Compounds of Cyanotrispyrazolylborates – Complexation-induced Ligand Isomerization”; Inorg. Chem. 2007, 46, 8662-8667. DOI: 10.1021/ic700628b

36. Smucker, B.W.; Van Stipdonk, M.J.; Eichhorn, D.M. “Incorporation of Thiolate Donation Using 2,2'-Dithiodibenzaldehyde: Complexes of a Pentadentate N2S3 Ligand With Relevance to the Active Site of Co Nitrile Hydratase”; J. Inorg. Biochem., 2007, 101, 1537-1542.

35. Zhao, N.; Van Stipdonk, M.J.; Eichhorn, D.M. “Syntheses and Crystal Structures of 3-tert-butyl-4-cyano Pyrazole and its Complexes with Cobalt(II), Manganese(II), and Copper(II)”; Polyhedron, 2007, 26, 2449-2454.

34. Kirgan, R.; Moore, C.; Eichhorn, D.M.; Rillema, D.P. “4-Acetylresorcinol”; Acta Cryst. 2007, E63, o4252.

33. Zhao, N.; Eichhorn, D.M. “Dichlorobis(3,5-dimethylpyrazole)copper(II)” Acta Cryst. 2005, E61, m822-m823.

32. Villegas, J.M.; Stoyanov, S.R.; Moore, C.E.; Eichhorn, D.M.; Rillema, D.P. “fac-Tricarbonyl(2,9-dimethyl-1,10-phenanthroline)(2,6-dimethylphenyl-isocyanide)rhenium(I) hexafluorophosphate” Acta Cryst. 2005, E61, m533-m534.

31. Zhong, J.; Lai, Z.; Groutas, C. S.; Wong, T.; Gan, X.; Alliston, K. R.; Eichhorn, D.; Hoidal, J. R.; Groutas, W. C. “Serendipitous Discovery of an Unexpected Rearrangement Leads to Two New Classes of Potential Protease Inhibitors” Bioorg. Med. Chem. 2004, 12, 6249-6254.

30. Oshin, K.; Landis, A. M.; Smucker, B. W.; Eichhorn, D. M.; Rillema, D. P. “fac-Bipyridyltricarbonyl(pyridine)rhenium(I) trifluoromethanesulfonate” Acta Cryst. 2004, E60, m1126-m1127.

29. Eller, C.; Smucker, B. W.; Kirgan, R.; Eichhorn, D. M.; Rillema, D. P. "5,5'-Dimethyl-2,2'-bipyrazine"; Acta Cryst. 2004, E60, o433-o434.

28. Siemer, C. J.; VanStipdonk, M. J.; Kahol, P. K.; Eichhorn, D. M.; "A Coordination Polymer from a Cyanoscorpionate Complex"; Polyhedron 2004, 23, 235-238.

27. Eichhorn, D. M.; Goswami, N.; "New Synthetic Techniques for the Incorporation of Thiolate Donation in Transition Metal Complexes"; Comm. Inorg. Chem. 2003, 24, 1-13. DOI: 10.1080/02603590390228164

26. Vongtragool, S.; Gorshunov, B.; Dressel, M.; Krzystek, J.; Eichhorn, D. M.; Telser, J.; "Direct Observation of Fine Structure Transitions in a Paramagnetic Nickel(II) Complex Using Far-Infrared Magnetic Spectroscopy: A New Method for Studying High-Spin Transition Metal Complexes"; Inorg Chem. 2003, 42, 1788-1790.

25. Gu, W.; Jacquamet, L.; Patil, D. S.; Wang, H.-X.; Evans, D. J.; Smith, M. C.; Millar, M.; Koch, S.; Eichhorn, D. M.; Latimer, M.; Cramer, S. P.; "Refinement of the Nickel Site Structure in Desulfovibrio gigas Hydrogenase Using Range-extended EXAFS Spectroscopy"; J. Inorg. Biochem. 2003, 93, 41-51.

24. Goswami, N.; Van Stipdonk, M. J.; Eichhorn, D. M.; "Formation of an ethylene-bridged bis(benzisothiazole) dication by oxidative decomplexation of Ni(tsalen) with FeCl3"; Inorg. Chem. Commun. 2003, 6, 86-89.

23. Siemer, C. J.; Meece, F. A.; Armstrong, W. H.; Eichhorn, D. M.; "Iron, Copper, and Cobalt Complexes of Hydrotris(3-phenylpyrazolyl)borate and Dihydrobis(3-phenylpyrazolyl)borate. Synthesis and X-ray Crystallographic Characterization"; Polyhedron 2001, 20, 2637-2646.

22. Siemer, C. J.; Goswami, N.; Van Stipdonk, M. J.; Eichhorn, D. M.; " Dihydrobis(4-cyano-3-phenylpyrazol-1-yl)borate: Homoleptic Mononuclear Cobalt(II) and Copper(II) Complexes With a Cyano-substituted Scorpionate Ligand."; Inorg. Chem., 2001 40, 4081-4084.

21. McCormick, B. J.; Siemer, C.; Afroz, F.; Wasson, J. R.; Eichhorn, D. M.; Scott, B.; Shah, S.; Noffsinger, K.; Kahol, P. K.; "The Copper Acetylenedicarboxylate System"Synthetic Metals, 2001, 120 , 969-970.

20. Shan, B.-Z.; Zhao, Q.; Goswami, N.; Eichhorn, D. M.; Rillema, D. P.; "Structure, NMR, and Other Physical and Photophysical Properties of Ruthenium Complexes Containing the 3,3'-Dicarboxyl-2,2'-Bipyridine Ligand"; Coord. Chem. Rev.; 2001, 211, 117-144.

19. Xue, W.-M.; Goswami, N.; Eichhorn, D. M.; Orizondo, P. L.; Rillema, D. P.; "Synthesis and Luminescence Properties of a Nonsymmetric Ligand-Bridged ReI-ReI Chromophore" Inorg. Chem. 2000, 39, 4460-4467.

18. Burns, D. H.; Chan, H.-K.; Miller, J. D.; Jayne, C. L; Eichhorn, D. M. " Synthesis, Modification, and Characterization of a Family of Homologs of exo-Calix[4]arene: exo-[n.m.n.m]Metacyclophanes, n,m≥3"; J. Org. Chem., 2000, 65, 5185-5196.

17. Goswami, N.; Eichhorn, D. M.; "Incorporation of Thiolate Donation Using 2,2'-Dithiodibenzaldehyde: Synthesis of Ni, Fe, and Cu Complexes. Crystal Structures of [M(tsalen)] (tsalen = N,N'-Ethylenebis(thiosalicylidene)imine); M = Cu, Ni) Showing a Tetrahedral Distortion of Cu(tsalen)"Inorg. Chim. Acta , 2000,303, 272-277.

16. Depriest, J.; Zheng, G. Y.; Goswami, N.; Eichhorn, D. M.; Woods, C.; Rillema, D. P.; "Structure, Physical and Photophysical Properties of Platinum(II) Complexes Containing Bidentate Aromatic and Bis(diphenylphosphino)methane as Ligands"; Inorg. Chem. 2000, 39, 1955-1963.

15. Deviprasad, G. R.; Eichhorn, D. M.; D'Souza, F. "Crystal Structure and Intermolecular Coordination Behavior of a Porphyrin Bearing Hydroquinone Receptor, meso-Mono(hydroquinonyl)triphenylporphyrinatozinc" J. Chem. Crystallogr. 1999 29, 849-853*

14. Goswami, N.; Eichhorn, D. M.; "A New Method for Incorporating Thiolate Donors into a Metal Coordination Sphere. Synthesis and Crystal Structures of the First Nickel Complexes of an N3S Ligand" Inorg. Chem. 1999, 36, 4329-4333.

13. Wang, Y.; Eichhorn, D. M.; Goswami, N.; Zhao, Q.; Rillema, D. P.; "Crystal Structure and Physical Properties of a Ruthenium(II) Bipyridine Complex" J. Chem. Crystallog.1999, 29, 277-281.

12. Huyett, J.E.; Choudhury, S.B.; Eichhorn, D. M.; Bryngelson, P.A.; Maroney, M.J.; Hoffman, B.M.; "Pulsed ENDOR and ESEEM Study of [Bis(maleonitriledithiolato)nickel]-: An Investigation into the Ligand Electronic Structure" Inorg. Chem. 1998, 37, 1361-1367.

11. Andersen, K.; Andersen, M.; Anderson, O. P.; Baum, S.; Baumann, T. G.; Beall, L. S.; Broderick, W. E.; Cook, A. S.; Eichhorn, D. M.; Goldberg, D.; Hope, H.; Jarrell, W.; Lange, S. J.; McCubbin, Q. J.; Mani, N. S.; Miller, T.; Garrido Montalban, A.; Rodriquez-Morgade, M. S.; Lee, S.; Nie, H.; Olmstead, M. M.; Sabat, M.; Sibert, J. W.; Stern, C.; White, A. J. P.; Williams, D. B. G.; Williams, D. J.; Barrett, A. G. M.; Hoffman, B. M.; “Star Porphyrazines and Related Multimetallic Macrocycles” J. Heterocyclic Chem. 1998, 35, 1013-1042.

10. Eichhorn, D. M.; Yang, S.; Jarrell, W.; Baumann, T.; Beall, L.S.; White, A.J.P.; Williams, D.J.; Barrett, A.G.M.; Hoffman, B.M.; “[60]Fullerene and TCNQ Donor-Acceptor Crystals of Octakis(dimethylamino)porphyrazine” J. Chem. Soc., Chem. Commun.1995, 1703-1704.

9. Broderick, W.E.; Eichhorn, D. M.; Liu, X.; Toscano, P.M.; Owen, S.; Hoffman, B.M.; "Three Phases of [Fe(C5Me5)2]+[TCNQ]-: Ferromagnetism in a New Structural Phase" J. Am. Chem. Soc. 1995, 117, 3641-3642.

8. Broderick, W.E.; Eichhorn, D. M.; Liu, X., Owens, S.; Toscano, P.M.; Hoffman, B.M.; "Ferromagnetism in a New Structural Phase of [Fe(C5Me5)2][TCNQ]" Mol. Cryst. Liq. Cryst. 1995, 273, 17-20.

7. Eichhorn, D. M.; Telser, J.; Stern, C.L.; Hoffman, B.M.; "Influence of Zero-Field Splitting and State Mixing on Ferromagnetic Exchange in the Integrated-Stack Charge-Transfer Salt [Cp*2Fe][Co(HMPA-B)]" Inorg. Chem. 1994, 33, 3533-3537.

6. Eichhorn, D. M.; Skee, D.C.; Broderick, W.E.; Hoffman, B.M.; "Ferromagnetism in Decamethylchromocenium tetracyanoethylenide" Inorg. Chem. 1993, 32, 491-492.

5. Eichhorn, D. M., Armstrong, W.H.; "A Remarkably Stable Mononuclear Manganese(III) Hydroxide Complex: [L1MnIII(OH)] (L1=bis(2-hydroxy, 5-nitrobenzyliminopropyl)¬methylamine)" J. Chem. Soc., Chem. Commun. 1992, 85-87.

4. Cramer, S.P.; deGroot, F.M.F.; Ma, Y.; Chen, C.T.; Sette, F.; Kipke, C.A.; Eichhorn, D. M.; Chan, M.K.; Armstrong, W.H.; Fuggle, J.C. "Ligand Field Strengths and Oxidation States from Manganese L-Edge Spectroscopy" J. Am. Chem. Soc. 1991, 113, 7937-7940.

3. Chambron, J.-C.; Eichhorn, D. M.; Franczyk, T.S.; Stearns, D.M. "Structure of [Hydro(trispyrazolylborato)-triphenylphosphinoiodomethyl] Rhodium(III)"Acta Crystallogr., 1991, C47, 1732-1734.

2. Low, D.W.; Eichhorn, D. M.; Draganescu, A.; Armstrong, W.H. "Structure and Properties of [Mn9O7(O2CC6H5)13py)2]: A Novel Nonanuclear Mn(III) Oxo-Carboxylate Species Synthesized by Employing an Oxygen Atom Transfer Agent" Inorg. Chem., 1991, 30, 877-878.

1. Eichhorn, D. M.; Armstrong, W.H. "M{(Hydrotris(3-phenyl-pyrazolyl)borate}2: Sterically Encumbered Iron(II) and Manganese(II) Complexes " Inorg. Chem. 1990, 29, 3607-3612.