The Catholic University of America

Dr. Greg Brewer
Chairman
Ordinary Professor, Inorganic Chemistry

                        
                                                 B. S.,     1978   College of Charleston
                                                 Ph. D.,   1982   University of Virginia
                                                              

                                                 Tel:         (202) 319-5385 and -5396 
                                                 Email:      brewer@cua.edu

 

Courses

CHEMISTRY 103-1   CHEMISTRY
104
  CONTACT ME

Summary of Research Interests

 Several areas of coordination chemistry are currently under investigation in our research group.

The molecules of interest are di-, tri- or polymetallic systems in which the first row transition metals are held in close proximity to one another by the presence of suitable bridging ligands. One aspect of this work is to develop synthetic strategies and conditions to prepare mononuclear complexes and to utilize these complexes as reagents in subsequent reactions to produce polynuclear species.

Typically the mononuclear starting complexes are the porphyrin or Schiff bas ligands. The former are ideal for providing a rigid framework with a strong field donor set while the latter are more flexible and easier to modify.

The magnetic properties of polymetallic species, antiferromagnetism and ferromagnetism, and the molecular interpretation of these bulk properties is also of intense interest. Other systems of investigation are intermediate (S=3/2) spin and spin crossover iron(III) complexes.

Binuclear compounds which also exhibit an intermediate spin or spin crossover are also under investigation as they are members of a new class of magnetic materials. The inorganic laboratories include a state-of-the-art inert atmosphere system and a low temperature Faraday balance.

 

Selected Publications
 

1. Oxidation of Phenacetin and Related Amides to Their Hydroxamic Acids. Brewer,G.A.; Sinn, E. Inorg. Chem. 1981, 20, 1823-1830.

2. Molecular and Electronic Structure of a Mixed Spin Diiron "Wedged" Metallacarborane, [(CH3)2C2B4H4]2(Fe(II) (low spin))Fe(II) (high spin))L2 [L2= 2THF or (OCH3)2C2H4], an Oxidative Fusion Intermediate. Grimes, R.N.; Maynard, R.B.; Sinn, E.; Brewer, G.; Long, G. J. Am. Chem. Soc. 1982, 104, 5987-5992.

3. Spectral Analysis of Bis(N,N?diisopropyldithiocarbamato) Nitrosyliron, Fe(NO)[S2CN(CH(CH3)2]2, and Preparation and Crystal Structure of its Cobalt Analogue. Brewer, G.A.; Butcher, R.J.; Letafat, B.; Sinn, E. Inorg. Chem. 1983, 22, 371-375.

4. Coordination of Planar C8H82- to Vanadium. Structural Characterization of (?8 - C8H8)V[(C2H5)2C2B4H4] Swisher, R.G.; Sinn, E.; Brewer, G.A.; Grimes, R.N. J. Am. Chem. Soc. 1983, 105, 2079-2080.

5. Reexamination of a Cytochrome Oxidase Model. A Noncoupled Iron-Copper Binuclear Complex. Brewer, G.A.; Sinn, E. Inorg. Chem. 1984, 23, 2537-2542.

6. Fast Atom Bombardment Mass Spectra of Metal Nucleotide Complexes. Brewer, G.A.; Grisham, C.M. Biomedical Mass Spectrometry 1984, 11, 400-402.

7. The Crystal and Molecular Structure of Cobalt Pentaamine Phosphate, a Na+?K+ ATPase Probe. Brewer, G.A.; Grisham, C.M.; Sinn, E.; Girard, J.; Drucker, S. Inorg. Chim. Acta 1984, 89, 103-109.

8. Evidence for the Existence of an Imidazole Bridge between a Nickel Schiff Base and Co(TPP). Brewer, G.A.; Sinn, E. Inorg. Chim. Acta 1984, 87, L41-43.

9. Copper(II) and Nickel(II) Complexes of some Unsymmetrical Tetradentate Schiff Base Ligands. Atkins, R.; Brewer, G.A.; Kokot, E.; Mockler, G.M.; Sinn, E. Inorg. Chem. 1985, 24, 127-134.

10. The Synthesis and Characterization of Nucleotide Complexes Involving an Asymmetric Metal. Brewer, G.A.; Grisham, C.M. Inorg. Chim. Acta Bioinorg. Chem. 1985, 106, 37-41.

11. 2,2'?Bipyrimidine Bridged Homobinuclear Complexes. Brewer, G.A.; Sinn, E. Inorg. Chem. 1985, 24, 4580-4584.

12. Evaluation of the Formation Constant for an Imidazolate Bridged Complex of Co(TPP). Brewer, G.A.; Brewer, C.T. Inorg. Chim. Acta 1985, 111, L5-7.

13. Imidazolate Bridged Heterobinuclear Complexes of Zinc(II)tetraphenylporphyrin. Modeling Cytochrome c Oxidase. Brewer, G.A.; Brewer, C.T. J. Inorg. Biochem. 1986, 26, 247-255.

14.Heterobinuclear Adducts of Copper Tetradentate Schiff Bases with Metal Hexafluroacetylacetonates. Brewer, G.A.; Sinn, E. Inorg. Chem. 1987, 26, 1529-1535.

15. Electronic and Solvent Effects in the Reaction of Zinc Porphyrins with a Metal Imidazolate Complex or 1?Methylimidazole. Cooper, J.B.; Brewer, C.T.; Brewer, G.A. Inorg. Chim. Acta 1987, 129, 25-30.

16. Heteronuclear Imidazolate Bridged Complexes of Iron(III) Porphyrins and Copper(II). Relevance to Cytochrome c Oxidase. Brewer, G.A.; Brewer, C.T. Inorg. Chem. 1987, 26, 3420-22.

17. A new FeCu2 Heterotrinuclear Complex [Fe(Cuprp2en)2(ClO4)2(H2O)2]. Definitive Evidence for a cis?Octahedral Configuration and an Isosceles Triangular Arrangement of Metal Atoms. Brewer, G.A.; Sinn, E. Inorg. Chim. Acta 1987, 134, 13-14.

18. Synthesis and Chemical Reactivity of Copper(II) and Nickel(II) Complexes of Imidazolate Containing Unsymmetrical Tetradentate Schiff?s Bases. Brewer, G.A.; Brewer, C.T. J. Chem. Soc., Chem. Comm. 1988, 854-856.

19. Effect of Molecular Complexation of the Porphyrin Ligand on the Axial Ligation of Fe(TPP)Cl. Brewer, G.A.; Brewer, C.T. Inorg. Chim. Acta 1988, 154, 67-71.

20. Ferromagnetic Coupling Via Imidazolate in an Iron(III) Porphyrin Dicopper(II) System. Koch, C.A.; Reed, C.A.; Brewer, G.A.; Rath, N.P.; Scheidt, W.R.; Gupta, G.; Lang, G. J. Am. Chem. Soc. 1989, 111, 7645-7648.

21. Can ?-Imidazolate Mediate Strong Antiferromagnetic Coupling? Koch, C.A.; Wang, B.; Brewer, G.; Reed, C.A. J. Chem. Soc. Chem. Comm. 1989, 1754-1755.

22. Steric Effects in the Reactions of Zinc(II) and Iron(III) "Capped" Porphyrins. Brewer, G.A.; Brewer, C.T. J. Chem. Soc. Dalton Trans. 1990, 843-847.

23. Synthesis of Imidazolate Bridged Di- and Tri-nuclear Ferromagnetic Complexes of Chromium(III) Porphyrins. Brewer, G.A.; Wang, R. J. Chem. Soc. Chem. Comm. 1990, 583-4.

24.Substituent Effects on the Enthalpy and Entropy for the Axial Ligation of Zinc Tetraphenylporphyrinates. Brewer, G.A.; Brewer, C.T.; Marbury, G.S. J. Chem. Soc. Dalton Trans. 1991, 1377-1378.

25. Synthesis, Structure, and Magnetic Properties of Cu4(?-OCMe3)6[OC(CF3)3]2 . and Cu3(?-OCMe3)4[OC(CF3)3]2 Purdy, A.P.; George, C.F.; Brewer, G.A. Inorg. Chem. 1992, 31, 2633-2638.

26. Evaluation of Magnetic Parameters of Polynuclear Complexes. Brewer, G.A. J. Chem. Ed. 1992, 69, 1006-1009.

27. Iron Octaethyltetraazaporphyrins: Synthesis, Characterization, Coordination Chemistry and Comparisons to Related Iron Porphyrins and Phthalocyanines. Fitzgerald, J.P.; Haggerty, B.S.; Rheingold, A. L.; May, L.; Brewer, G.A. Inorg. Chem. 1992, 31, 2006-2013.

28. Reaction of Sterically Hindered Imidazolate Complexes with Iron Porphyrins. Brewer, G.A.; Brewer, C.T. J. Chem. Soc. Dalton Trans. 1992, 1669-1672.

29. Magnetic Interactions in Dinuclear Complexes of Cr(salen)+. Brewer, G.A.; Brewer, C.T. Inorg. Chim. Acta 1992, 196, 1-5.

30. Synthesis of Imidazolate Bridged Dinuclear Cu(II)-Fe(III) Porphyrins. Brewer, G.A.; Wang, R. Inorg. Chim. Acta 1993, 206, 117-121.

31. Spin Crossover in Heterodinuclear Iron(III) Schiff Base Complexes. Brewer, G.A.; Wang, R.; May, L.; Brewer, C. T.; Sitar, J. J. Chem. Soc. Dalton Trans. 1993, 151-155.

32. Pentamethylcyclopentadienylmolybdenum(IV) Chloride. Synthesis, Structure, and Properties. Abugideiri, F.; Brewer, G. A.; Desai, J. U.; Gordon, J. C.; Poli, R. Inorg. Chem. 1994, 33, 3745-3751.

33. Synthesis of an Unsymmetrical Dinucleating Ligand that leads to a Asymmetric Di-Copper(II) Complex Having Different Sets at Each Copper. Kamaras, P.; Cajulis, M. C.; Rapta, M.; Brewer, G. A.; Jameson, G. B. J. Am. Chem. Soc. 1994, 116, 10334-10335.

34. Structure and Magnetism of Electronically Distorted Iron(III) Schiff Base Complexes. Brewer, C. T.; Brewer, G. A.; Jameson, G.; Kamaras, P. May, L. J. Chem. Soc. Dalton Trans. 1995, 37-43.

35. Spin Crossover Complexes of Iron(III) with an N4 Tetradentate Schiff Base Ligand. Brewer, G.; Jasinski, J. P; Mahany, W.; May, L; Prytkov, S. Inorg. Chim. Acta. 1995, 232, 183-187.

36. Coordination Modes of Water-Derived Bridging Ligands in Diiron(III) Complexes: Stabilization of an Oxo-Hydroxo Bridge by Hydrogen Bonding. Brewer, G.; Jameson, G. B.; Kamaras, P.; Rapta, M. J. Am. Chem. Soc. 1995, 117, 12865-12866.

37. Intermediate Spin Iron(III) Octaethyltetraazaporphyrinates with weekly coordinating anions: synthesis, characterization, and crystal structure. Brewer, C. T.; Brewer, G. A.; Fitzgerald, J. P.; May, L.; Rheingold, A. L. J. Chem. Soc. Dalton Trans. 1996, 1249-1253.

38. The Synthesis and Structural Characterization of Metal Complexes of an Unsymmetrical N3O Tetradentate Schiff Base Ligand. Brewer, G. A.; Kamaras, P.; May, L.; Prytkov, S.; Rapta, M. Inorg. Chim. Acta 1998, 279, 111-115.

39. Synthesis and Characterization of a Neutral, Low Spin Iron(III) Complex of a Hezadentate Tripodal Ligand Containing three Imidazolate Arms. Use as a Dinucleating Agent. Brewer, G. A., Brewer, C. T., Scheidt, W. R., and Mueller, I., Inorg. Chim. Acta, 1998, 278, 197-201.

40. Ligand Oxidation in N4 Tetradentate Schiff Base Complexes Catalyzed by Copper(II) Hexafluoroacetylacetonate Dihydrate: Reaction Details and Structures. Brewer, G. A.; Kamaras, P.; Prytkov, S.; Shang, M.; Scheidt W. R. J. C. S. Dalton Trans. 1999, 4511-4517.

41. Synthesis and Characterization of iron(III) Complexes of N4 Schiff Base Macrocycles. Brewer, G. A.; Kamaras, P.; May, L.; Prytkov, S.; Inorg. Chem Comm. 1999, 2, 3-6.

42. Synthesis and Structural and Magnetic Characterization of Discrete Phenolato and Imidazolate Bridged Gd(III)- M(II) [M=Cu, Ni] Dinuclear Complexes. Brewer, C.; Brewer, G.; Scheidt, W. R.; Shang, M., Carpenter, E. E. Inorg. Chim. Acta. 313, 2001, 313,65-70.

43. Synthesis and Structural Characterization of Copper Complexes of N4 Tetradentate Schiff bases Derived from N-alkylated 2-aminabenzaldehyde. Effects of Cyclization, Oxidation, and Dinucleation. Brewer, C. T.; Brewer, G.; Kamaras, P.; Prytkov, S.; Shang, M.; Scheidt, W. R. Inorg. Chim. Acta, 2001, 321, 175-180.

44. Proton Control of Oxidation and Spin State in a Series of Iron Tripodal Imidazole Complexes. Brewer, C.; Brewer, G.; Luckett, C.; Marbury, G. S.; Viragh, C.; Beatty, A. M.; Scheidt, W. R. Inorg. Chem. 2004, 43, 2402-15.

45. Synthesis and Characterization of Tripodal Iron(II) Complexes Prepared from 2-Pyridinecarboxaldehyde and 1-Methyl-2-imidazolecarboxaldehyde: Stabilization of Iron(II) Cations with N6 Donor Sets. Brewer, G.; Luckett, C. E.; May, L.; Beatty, A. M.; Scheidt, W. R. Inorg. Chim. Acta 2004, 357, 2390-6.

46. Preparation and Separation of Asymmetric Tripodal Iron Complexes of Tren and Selected Aldehydes. Brewer, G.; Luckett, C. E. Inorg. Chim. Acta 2005, 358, 239-245.

47. Conformational Control of Spin State in Iron(II) Tripodal Imidazole Complexes. Brewer, C.; Brewer, G.; Viragh, C.; Patil, G.; Sun, Y.; Butcher, R. J. Inorg. Chim. Acta, 2005, 358, 3441-48.

48. Synthesis and Characterization of a Novel Gd(III)?Cu(II) Dinuclear Adduct. Brewer, C.; Brewer, G.; Shang, M.; Scheidt, W. R. Inorg. Chem. Comm., 2005, 8, 676-9.

49. Synthesis and Characterization of Seven-Coordinate Tripodal Imidazole Complexes of Iron(II) and Manganese(II). Brewer, C.; Brewer, G.; Butcher, R. J.; Carpenter, E. E.; Cuenca, L.; Schmiedekamp, A. M.; Viragh, C. J. Chem. Soc. Dalton Trans., in press.

50. Synthesis and Characterization of Cu(II) and Ni(II) Complexes of a Tripodal Ligand Containing Imidazoles. Brewer, C.; Brewer, G.; Butcher, R. J.; Carpenter, E. E. Inorg. Chim. Acta, in press.

51. Synthesis and Characterization of Manganese(II) and Iron(III) d5 Tripodal Complexes. Effect of Oxidation State, Protonation State and Ligand Conformation on Coordination Number and Spin State. Brewer, C.; Brewer, G.; Butcher, R. J.; Carpenter, E. E.; Cuenca, L.; Noll B. C.; Scheidt, W. R.; Viragh, C.; Zavalij, P. Y.; Zielaski, D. J. Chem. Soc. Dalton Trans., in press.

52. A Supramolecular Spin Crossover Mixed Valence Iron(II)-Iron(III) Complex. Brewer, C.; Brewer, G. Butcher, R. J.; Carpenter, E. E.; Viragh, C. submitted to Angew. Chem. Int. Ed.

53. Structure, Properties, and Reactivity of Iron Complexes of Tripodal Imidazole Complexes. Brewer, G. manuscript in preparation, Invited Review for Inorg. Chem. Comm.

54.Use of Tripodal Iron Imidazolate Complexes as Nucleophiles. Brewer, G.; Butcher, R. J.; May, L. Manuscript in preparation, New Journal of Chemistry.

55. Spin Crossover in Iron Complexes of Tripodal Imidazole Ligands: A DFT Computational Study. Brewer, G.; Schmiedekamp, A. M.; Olida, M. J. Manuscript in preparation, Inorg. Chem