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Aμ-oxo vanadium(V) dimeric complex, μ-oxido-bis[(2,2′-{[ethane-1,2-diylbis(azanediyl)]bis(methylene)}diphenolato)oxidovanadium(V)], [V2(C16H18N2O2)2O3] (1), was crystallized by slow evaporation from an ethanol solution. Theμ-oxo dimer crystallizes in the monoclinic space groupC2/cwhere the salan ligand1acoordinates to the vanadium center in a κ2N,κ2Ofashion, forming a distorted octahedral geometry. The bridging oxo ligand lies on a crystallographic twofold axis. The unit cell consists of four molecules of1that are linked by C—H...·πareneinteractions as well as intramolecular hydrogen bonding.
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Speciation and Photoluminescent Properties of a 2,6‐Bis(pyrrol‐2‐yl)pyridine in Three Protonation States
Abstract 2,6‐Bis(pyrrol‐2‐yl)pyridines are important building blocks for supramolecular assemblies and photoluminescent main group and transition metal compounds. Sterically encumbered 2,6‐bis(5‐(2,4,6‐trimethylphenyl)‐3‐phenyl‐1H‐pyrrol‐2‐yl)pyridine, H2MesPDPPh, can adopt monomeric and dimeric structures in the solid state and in solution, controlled by competing inter‐ and intramolecular hydrogen bonds. Deprotonation in the presence of lithium cations provides Li2MesPDPPh, which can be isolated in monomeric and dimeric forms depending on solvent polarity. Protonation of H2MesPDPPhdisrupts intramolecular hydrogen bonding and provides the monomeric pyridinium salt [H3MesPDPPh]Cl. Independent of solvent polarity, all three derivatives exhibit intense fluorescence in solution. The absorption and emission spectra are highly sensitive to the level of protonation, which can be rationalized by the effects of (de)protonation on the HOMO and LUMO of the tricyclic π‐system.
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- Award ID(s):
- 1752738
- PAR ID:
- 10418515
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemPhotoChem
- Volume:
- 7
- Issue:
- 8
- ISSN:
- 2367-0932
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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