Single-Acetylene Linked Porphyrin Nanorings
نویسندگان
چکیده
The synthesis of ethyne-linked porphyrin nanorings has been achieved by template-directed Sonogashira coupling. The cyclic hexamer and octamer are predicted by density functional theory to adopt low symmetry conformations, due to dihedral twists between neighboring porphyrin units, but their symmetries are effectively D6h and D8h, respectively, in solution by 1H NMR. The fluorescence spectra indicate that the singlet excited states of these nanorings are highly delocalized.
منابع مشابه
Unexpected Interactions between Alkyl Straps and Pyridine Ligands in Sulfur-Strapped Porphyrin Nanorings
Strapped or "basket-handle" porphyrins have been investigated previously as hemoglobin mimics and catalysts. The facial selectivity of their interactions with axial ligands is a sensitive test for noncovalent bonding. Here the binding of pyridyl ligands to zinc porphyrins with thioester-linked alkyl straps is investigated in solution by NMR spectroscopy and UV-vis titration, and in the solid st...
متن کاملOn the Influence of the Bridge on Triplet State Delocalization in Linear Porphyrin Oligomers
The extent of triplet state delocalization is investigated in rigid linear zinc porphyrin oligomers as a function of interporphyrin bonding characteristics, specifically in meso-meso singly linked and β,meso,β fused structures, using electron paramagnetic resonance techniques. The results are compared with those of earlier measurements on porphyrin oligomers with alkyne linkers exhibiting diffe...
متن کاملHeight dependent molecular trapping in stacked cyclic porphyrin nanorings.
Stacked layers of cyclic porphyrin nanorings constitute nanoscale receptacles with variable height and diameter which preferentially adsorb sublimed molecules. Using scanning tunnelling microscopy we determine the filling capacity of these nanoring traps, and the dependence of adsorbate capture on stack height and diameter.
متن کاملSynthesis of Five‐Porphyrin Nanorings by Using Ferrocene and Corannulene Templates
The smallest and most strained member of a family of π-conjugated cyclic porphyrin oligomers was synthesized by using pentapyridyl templates based on ferrocene and corannulene. Both templates are effective for directing the synthesis of the butadiyne-linked cyclic pentamer, despite the fact that the radii of their N5 donor sets are too small by 0.5 Å and 0.9 Å, respectively (from DFT calculatio...
متن کاملPreconcentration of Pb(II) by Graphene Oxide with Covalently Linked Porphyrin Adsorbed on Surfactant Coated C18 before Determination by FAAS
A simple, highly sensitive, accurate and selective method for determination of trace amounts of Pb(II) in water samples is presented. A novel Graphene oxide with covalently linked porphyrin solid-phase extraction adsorbent was synthesized by covalently linked porphyrin onto the surfaces of graphite oxides. The stability of a chemically (GO-H2P) especially in concentrated hydrochloric acid was s...
متن کامل