uu.seUppsala University Publications
Change search
ReferencesLink to record
Permanent link

Direct link
Spectroscopic and Structural Investigations Reveal the Signaling Mechanism of a Luminescent Molybdate Sensor
Show others and affiliations
2011 (English)In: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 50, no 3, 1105-1115 p.Article in journal (Refereed) Published
Abstract [en]

A heteroditopic ligand H(2)-L consisting of a dihydroxybenzene (catechol)-unit linked via an amide bond to a pyridyl-unit and its methyl-protected precursor Me(2)-L were synthesized, characterized, and their photophysical properties investigated. The three accessible protonation states of the ligand, H(3)-L(+), H(2)-L, and H-L(-), showed distinct (1)H NMR, absorption and emission spectroscopic characteristics that allow pH-sensing. The spectroscopic signatures obtained act as a guide to understand the signaling mechanism of the luminescent pH and molybdate sensor [Re-(bpy)(CO)(3)(H(2)-L)](+). It was found that upon deprotonation of the 2-hydroxy group of H(2)-L, a ligand-based absorption band emerges that overlaps with the Re(d pi)-> bpy metal-to-ligand charge transfer (MLCT) band of the sensor, reducing the quantum yield for emission on excitation in the 370 nm region. In addition, deprotonation of the catechol-unit leads to quenching of the emission from the Re(d pi)-> bpy (3)MLCT state, consistent with photoinduced electron transfer from the electron-rich, deprotonated catecholate to the Re-based luminophore. Finally, reaction of 2 equiv of [Re(bpy)(CO)(3)(H(2)-L)](+) with molybdate was shown to give the zwitterionic Mo(VI) complex [MoO(2){Re(CO)(3)-(bpy)(L)}(2)], as confirmed by electrospray ionization (ESI) mass spectrometry and X-ray crystallography. The crystal structure determination revealed that two fully deprotonated sensor molecules are bound via their oxygen-donors to a cis-dioxo-MoO(2) center.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2011. Vol. 50, no 3, 1105-1115 p.
National Category
Physical Chemistry
URN: urn:nbn:se:uu:diva-166114DOI: 10.1021/ic1019422ISI: 000286688700052OAI: oai:DiVA.org:uu-166114DiVA: diva2:476198
Available from: 2012-01-11 Created: 2012-01-10 Last updated: 2013-05-17Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Hammarström, Leif
By organisation
Chemical Physics
In the same journal
Inorganic Chemistry
Physical Chemistry

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 408 hits
ReferencesLink to record
Permanent link

Direct link