Header

UZH-Logo

Maintenance Infos

Structures of rhenium(I) complexes with 3-hydroxyflavone and benzhydroxamic acid as O,O′-bidentate ligands and confirmation of π-stacking by solid-state NMR spectroscopy


Schutte-Smith, Marietjie; Roodt, Andreas; Alberto, Roger; Twigge, Linette; Visser, Hendrik Gideon; Kirsten, Leo; Koen, Renier (2019). Structures of rhenium(I) complexes with 3-hydroxyflavone and benzhydroxamic acid as O,O′-bidentate ligands and confirmation of π-stacking by solid-state NMR spectroscopy. Acta Crystallographica. Section C: Structural Chemistry, 75(4):378-387.

Abstract

The synthesis and crystal structures of two new rhenium(I) complexes obtainedutilizing benzhydroxamic acid (BHAH) and 3-hydroxyflavone (2-phenyl-chromen-4-one, FlavH) as bidentate ligands, namely tetraethylammoniumfac-(benzhydroxamato-2O,O0)bromidotricarbonylrhenate(I), (C8H20N)[ReBr(C7H6-NO2)(CO)3],1,andfac-aquatricarbonyl(4-oxo-2-phenylchromen-3-olato-2O,O0)-rhenium(I)–3-hydroxyflavone (1/1), [Re(C15H9O3)(CO)3(H2O)]C15H10O3,3, arereported. Furthermore, the crystal structure of free 3-hydroxyflavone, C15H10O3,4, was redetermined at 100 K in order to compare the packing trends and solid-state NMR spectroscopy with that of the solvate flavone molecule in3.Thecompounds were characterized in solution by1H and13C NMR spectroscopy,and in the solid state by13C NMR spectroscopy using the cross-polarizationmagic angle spinning (CP/MAS) technique. Compounds1and3both crystallizein the triclinic space groupP1 with one molecule in the asymmetric unit, while4crystallizes in the orthorhombic space groupP212121. Molecules of1and3generate one-dimensional chains formed through intermolecular interactions. Acomparison of the coordinated 3-hydroxyflavone ligand with the uncoordinatedsolvate molecule and free molecule4shows that the last two are virtuallycompletely planar due to hydrogen-bonding interactions, as opposed to theformer, which is able to rotate more freely. The differences between the solid-and solution-state13C NMR spectra of3and4are ascribed to inter- andintramolecular interactions. The study also investigated the potential labelling ofboth bidentate ligands with the correspondingfac-99mTc-tricarbonyl synthon.All attempts were unsuccessful and reasons for this are provided.

Abstract

The synthesis and crystal structures of two new rhenium(I) complexes obtainedutilizing benzhydroxamic acid (BHAH) and 3-hydroxyflavone (2-phenyl-chromen-4-one, FlavH) as bidentate ligands, namely tetraethylammoniumfac-(benzhydroxamato-2O,O0)bromidotricarbonylrhenate(I), (C8H20N)[ReBr(C7H6-NO2)(CO)3],1,andfac-aquatricarbonyl(4-oxo-2-phenylchromen-3-olato-2O,O0)-rhenium(I)–3-hydroxyflavone (1/1), [Re(C15H9O3)(CO)3(H2O)]C15H10O3,3, arereported. Furthermore, the crystal structure of free 3-hydroxyflavone, C15H10O3,4, was redetermined at 100 K in order to compare the packing trends and solid-state NMR spectroscopy with that of the solvate flavone molecule in3.Thecompounds were characterized in solution by1H and13C NMR spectroscopy,and in the solid state by13C NMR spectroscopy using the cross-polarizationmagic angle spinning (CP/MAS) technique. Compounds1and3both crystallizein the triclinic space groupP1 with one molecule in the asymmetric unit, while4crystallizes in the orthorhombic space groupP212121. Molecules of1and3generate one-dimensional chains formed through intermolecular interactions. Acomparison of the coordinated 3-hydroxyflavone ligand with the uncoordinatedsolvate molecule and free molecule4shows that the last two are virtuallycompletely planar due to hydrogen-bonding interactions, as opposed to theformer, which is able to rotate more freely. The differences between the solid-and solution-state13C NMR spectra of3and4are ascribed to inter- andintramolecular interactions. The study also investigated the potential labelling ofboth bidentate ligands with the correspondingfac-99mTc-tricarbonyl synthon.All attempts were unsuccessful and reasons for this are provided.

Statistics

Citations

Dimensions.ai Metrics
6 citations in Web of Science®
6 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

35 downloads since deposited on 11 Feb 2020
11 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Department of Chemistry
Dewey Decimal Classification:540 Chemistry
Scopus Subject Areas:Physical Sciences > Condensed Matter Physics
Physical Sciences > Physical and Theoretical Chemistry
Physical Sciences > Inorganic Chemistry
Physical Sciences > Materials Chemistry
Language:English
Date:1 April 2019
Deposited On:11 Feb 2020 16:21
Last Modified:22 Jun 2024 01:42
Publisher:Wiley-Blackwell Publishing, Inc.
ISSN:2053-2296
OA Status:Green
Publisher DOI:https://doi.org/10.1107/s2053229619002717
  • Content: Published Version