title: π-Extension in expanded porphyrins: cyclo[4]naphthobipyrrole.
abstract: The π-extended cyclo[4]naphthobipyrrole 1a has been prepared via an Fe(III)-mediated oxidative cyclization of an alkyl-substituted naphthobipyrrole. The structure of this new expanded porphyrin, isolated as the deprotonated sulfate salt, was characterized by spectroscopic means, as well through a single crystal X-ray diffraction analysis. Salt 1a displays a total of four well-resolved redox waves as determined by cyclic voltammetry. It also displays bathochromically shifted near-IR absorption maxima compared to the diprotonated forms of nonannulated cyclo[8]pyrroles.
authors.affiliation: Department of Chemistry and Biochemistry, The University of Texas at Austin, 1 University Station A5300, Austin, Texas 78712, USA.
authors.forename: Vladimir V
authors.initials: VV
authors.lastname: Roznyatovskiy
authors.forename: Jong Min
authors.initials: JM
authors.lastname: Lim
authors.forename: Vincent M
authors.initials: VM
authors.lastname: Lynch
authors.forename: Byung Sun
authors.initials: BS
authors.lastname: Lee
authors.forename: Dongho
authors.initials: D
authors.lastname: Kim
authors.forename: Jonathan L
authors.initials: JL
authors.lastname: Sessler