title: Transition-metal complexes of expanded porphyrins.
abstract: Over the last 2 decades, the rapid development of new synthetic routes for the preparation of expanded porphyrin macrocycles has allowed for the exploration of a new frontier consisting of "porphyrin-like" coordination chemistry. In this Account, we summarize our exploratory forays into the still relatively poorly explored area of oligopyrrolic macrocycle metalation chemistry. Specifically, we describe our successful formation of both mono- and binuclear complexes and, in doing so, highlight the diversity of coordination modes available to expanded porphyrin-type ligands. The nature of the inserted cation, the emerging role of tautomeric equilibria, and the importance of hydrogen-bonding interactions in regulating this chemistry are also discussed.
authors.affiliation: Department of Chemistry and Biochemistry, 1 University Station A-5300, The University of Texas at Austin, Austin, Texas 78712, USA. sessler@mail.utexas.edu
authors.forename: Jonathan L
authors.initials: JL
authors.lastname: Sessler
authors.forename: Elisa
authors.initials: E
authors.lastname: Tomat
mesh_terms: D002412:Cations; D006860:Hydrogen Bonding; D008024:Ligands; D047028:Macrocyclic Compounds / Q000737:chemistry*; D008968:Molecular Conformation; D009942:Organometallic Compounds / Q000737:chemistry*; D011166:Porphyrins / Q000737:chemistry*; D028561:Transition Elements / Q000737:chemistry*
chemical_list: D002412:Cations; D008024:Ligands; D047028:Macrocyclic Compounds; D009942:Organometallic Compounds; D011166:Porphyrins; D028561:Transition Elements