Photocontrol of Polar Aromatic Interactions by a Bis-Hemithioindigo Based Helical Receptor

Manuel Guentner; Edgar Uhl; Peter Mayer; Henry Dube

doi:10.1002/chem.201604237

Photocontrol of Polar Aromatic Interactions by a Bis-Hemithioindigo Based Helical Receptor

Chemistry. 2016 Nov 7;22(46):16433-16436. doi: 10.1002/chem.201604237. Epub 2016 Oct 10.

Authors

Manuel Guentner¹, Edgar Uhl¹, Peter Mayer¹, Henry Dube²

Affiliations

¹ Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, Munich, Germany.
² Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, Munich, Germany. Henry.Dube@lmu.de.

PMID: 27644003
DOI: 10.1002/chem.201604237

Abstract

The first example of a bis-hemithioindigo (bis-HTI)-based molecular receptor was realized. Its folding and selective binding affinity for aromatic guest molecules can be precisely controlled by visible light and heat. The thermodynamically stable state of the bis-HTI is the s-shaped planar Z,Z-configuration. After irradiation with 420 nm light only the E,Z-configuration is formed in a highly selective photoisomerization. The E,Z-isomer adopts a helical conformation because of the implementation of repulsive steric interactions. The E,Z-configured helix is able to recognize electron-poor aromatic guests exclusively through polar aromatic interactions and also distinguishes between regioisomers. After heating, the Z,Z-configuration is completely restored and the aromatic guest molecule is efficiently released.

Keywords: host-guest systems; molecular recognition; photochemistry; photochromism; receptors.