title: Sandwich compounds of cyanotrispyrazolylborates: complexation-induced ligand isomerization.
abstract: Reaction of the new cyanoscorpionate ligand, hydrotris(4-cyano-3-phenyl)pyrazolylborate (Tp(Ph),(4CN)) with Co(II), Mn(II), and Fe(II) unexpectedly results in the isolation only of crystals containing sandwich complexes in which the ligands have been isomerized to produce the heterocyanoscorpionate hydrobis(4-cyano-3-phenylpyrazolyl)(4-cyano-5-phenylpyrazolyl)borate (Tp(Ph),(4CN*)). The three complexes have been characterized crystallographically and are isostructural, with each ligand acting in a tridentate manner toward the metal. The isomerization of the ligand appears to be more facile than that of the analogous non-cyano ligand, Tp(Ph), with which crystals of the unisomerized sandwich compound have been isolated for Mn(II) and Fe(II).
authors.affiliation: Department of Chemistry, Wichita State University, Wichita, Kansas 67260, USA.
authors.forename: Ningfeng
authors.initials: N
authors.lastname: Zhao
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Van Stipdonk
authors.forename: Cary
authors.initials: C
authors.lastname: Bauer
authors.forename: Charles
authors.initials: C
authors.lastname: Campana
authors.forename: David M
authors.initials: DM
authors.lastname: Eichhorn