title: Synthesis of zinc, copper, nickel, cobalt, and iron complexes using tris(pyrazolyl)methane sulfonate ligands: a structural model for N,N,O binding in metalloenzymes.
abstract: Ligands of intermediate steric bulk were designed to mimic metalloenzymes with histidine and carboxlyate binding sites. The reaction between tris(3-isopropylpyrazolyl)methane and butyllithium followed by SO3NMe3 in THF yielded the new ligand lithium tris(3-isopropylpyrazolyl)methane sulfonate (LiTpmsiPr). Various metal salts reacted with LiTpmsiPr to give the octahedral complexes M(TpmsiPr)2 (M = Zn, Cu, Ni, Co, Fe) in which each ligand has N,N,O binding to the metal. In the reaction between LiTpmsiPr and ZnCl2, in addition to the major product Zn(TpmsiPr)2, [LiTpmsiPrZnCl2].2THF was also formed as a minor product with a tetrahedral zinc atom coordinated to either N,N,Cl,Cl in the solid phase or N,N,N,Cl in acetonitrile solution. Although TpmsiPr is coordinatively flexible and can act as a bipodal or tripodal ligand, it appears to favor the formation of octahedral L2M complexes.
authors.affiliation: Department of Chemistry, Salisbury University, 1101 Camden Avenue, Salisbury, Maryland 21801, USA. etpapish@salisbury.edu
authors.forename: Elizabeth T
authors.initials: ET
authors.lastname: Papish
authors.forename: Michael T
authors.initials: MT
authors.lastname: Taylor
authors.forename: Finith E
authors.initials: FE
authors.lastname: Jernigan
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Rodig
authors.forename: Robert R
authors.initials: RR
authors.lastname: Shawhan
authors.forename: Glenn P A
authors.initials: GP
authors.lastname: Yap
authors.forename: Fernando A
authors.initials: FA
authors.lastname: Jové
mesh_terms: D001665:Binding Sites; D015392:Chemistry, Inorganic / Q000379:methods*; D003035:Cobalt; D003300:Copper; D004798:Enzymes / Q000737:chemistry* / Q000378:metabolism*; D007501:Iron; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D008670:Metals / Q000737:chemistry / Q000378:metabolism*; D008956:Models, Chemical; D015394:Molecular Structure; D009532:Nickel; D009584:Nitrogen / Q000737:chemistry / Q000378:metabolism; D010100:Oxygen / Q000737:chemistry / Q000378:metabolism; D011720:Pyrazoles / Q000737:chemistry; D012995:Solubility; D013056:Spectrophotometry, Ultraviolet; D013451:Sulfonic Acids / Q000737:chemistry; D015032:Zinc
chemical_list: D004798:Enzymes; D008024:Ligands; D008670:Metals; D011720:Pyrazoles; D013451:Sulfonic Acids; C515920:tris(pyrazolyl)methane; D003035:Cobalt; D003300:Copper; D009532:Nickel; D007501:Iron; D015032:Zinc; D009584:Nitrogen; D010100:Oxygen