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Updated: May 15, 2026
Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Synthesis, structure, and reactivity of iridium(III) complexes containing a 4,6-dimethyl-1,3-benzenediphenylimine
Leah A Wingard1, Mathew C Finniss, Michael Norris
1W. R. Kenan Laboratory, Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290, United States. leah.a.wingard@gmail.com
Abstract:
A nonheterocyclic bis(imino)aryl ligand with blocking methyl substituents, 4,6-dimethyl-1,3-benzenediphenylimine (NCHN), has been synthesized. Metalation via oxidative addition proceeds under mild conditions with the Ir(I) reagent [Ir(CH(2)═CH(2))(2)(Cl)](2) to produce the Ir(III) product (NCN)Ir(CH(2)CH(3))(Cl). Neutral nucleophiles such as water or triphenylphosphine add readily to the vacant sixth coordination site. Protonation of the ethyl group results in loss of ethane and formation of a dicationic chloride-bridged (NCN)Ir dimer. Alternatively, the chloride ligand can be abstracted from (NCN)Ir(CH(2)CH(3))(Cl) to provide access to various neutral and cationic species, including (NCN)Ir(CH(2)CH(3))(OAc) (OAc = acetate), [(NCN)Ir(CH(2)CH(3))(bpy)][BF(4)] (bpy = 4,4'-bipyridine), [(NCN)Ir(CH(2)CH(3))(NCCH(3))(2)][BF(4)], and [(NCN)Ir(CH(2)CH(3))(OH(2))(2)][BF(4)], which is water soluble.
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