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Photocontrol of Anion Binding Affinity to a Bis-urea Receptor Derived from Stiff-Stilbene.

ABSTRACT: Toward the development of photoresponsive anion receptors, a stiff-stilbene photoswitch has been equipped with two urea anion-binding motifs. Photoinduced E/Z isomerization has been studied in detail by UV-vis and NMR spectroscopy. Titration experiments (¹H NMR) reveal strong binding of acetate and phosphate to the (Z)-isomer, in which the urea groups are closely together. Isomerization to the (E)-form separates the urea motifs, resulting in much weaker binding. Additionally, geometry optimizations by density functional theory (DFT) illustrate that oxo-anion binding to the (Z)-form involves four hydrogen bonds.

SUBMITTER: Wezenberg SJ

PROVIDER: S-EPMC5330661 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Photocontrol of Anion Binding Affinity to a Bis-urea Receptor Derived from Stiff-Stilbene.

Wezenberg Sander J SJ Feringa Ben L BL

Organic letters 20170111 2

Toward the development of photoresponsive anion receptors, a stiff-stilbene photoswitch has been equipped with two urea anion-binding motifs. Photoinduced E/Z isomerization has been studied in detail by UV-vis and NMR spectroscopy. Titration experiments (<sup>1</sup>H NMR) reveal strong binding of acetate and phosphate to the (Z)-isomer, in which the urea groups are closely together. Isomerization to the (E)-form separates the urea motifs, resulting in much weaker binding. Additionally, geometry ...[more]

PMID: 28074657

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