title: Coordinative self-assembly and solution-phase X-ray structural characterization of cavity-tailored porphyrin boxes.
abstract: Combining linear Zn porphyrin trimers with orthogonally derivatized porphyrin dimers leads rapidly and spontaneously to the formation of monodisperse, torsionally constrained boxes comprising six components and a total of 16 metalloporphyrins. In situ X-ray scattering measurements confirm the formation of monodisperse assemblies of precisely the size expected from model box structures. While simple subunits yield highly symmetrical boxes, we find that sterically demanding subunits produce unusual twisted boxes. Previous studies of porphyrin-based box-like assemblies (squares) for selective catalysis and molecular sieving revealed two function-inhibiting structural problems: torsional motion along the metal-porphyrin-metal axis and ambiguous outside versus inside functionalization (via axial ligation of available Zn(II) sites). The new 16-porphyrin box assemblies eliminate both problems.
authors.affiliation: Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA.
authors.forename: Suk Joong
authors.initials: SJ
authors.lastname: Lee
authors.forename: Karen L
authors.initials: KL
authors.lastname: Mulfort
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Zuo
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Goshe
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Wesson
authors.forename: T SonBinh
authors.initials: TS
authors.lastname: Nguyen
authors.forename: Joseph T
authors.initials: JT
authors.lastname: Hupp
authors.forename: David M
authors.initials: DM
authors.lastname: Tiede
mesh_terms: D015394:Molecular Structure; D011166:Porphyrins / Q000737:chemistry*; D012996:Solutions; D014961:X-Ray Diffraction; D015032:Zinc / Q000737:chemistry*
chemical_list: D011166:Porphyrins; D012996:Solutions; D015032:Zinc