Switching with orthogonal stimuli: electrochemical ring-closure and photochemical ring-opening of bis(thiazolyl)maleimides
- 18 December 2012
- journal article
- Published by Royal Society of Chemistry (RSC) in Chemical Science
- Vol. 4 (3), 1028-1040
- https://doi.org/10.1039/c2sc21681g
Abstract
The photochemistry as well as electrochemistry of novel donor–acceptor bis(morpholinothiazolyl)–maleimides has been investigated. Proper substitution of these diarylethene-type molecular switches leads to the unique situation in which their ring-closure can only be accomplished electrochemically, while ring-opening can only be achieved photochemically. Hence, these switches operate with orthogonal stimuli, i.e. redox potential and light, respectively. The switch system could be optimized by introducing trifluoromethyl groups at the reactive carbon atoms in order to avoid by-product formation during oxidative ring closure. Both photochemical and electrochemical pathways were investigated for methylated, trifluoromethylated, and nonsymmetrical bis(morpholinothiazolyl)maleimides as well as the bis(morpholinothiazolyl)cyclopentene reference compound. With the aid of the nonsymmetrical “mixed” derivative, the mechanism of electrochemically driven ring closure could be elucidated and seems to proceed via a dicationic intermediate generated by two-fold oxidation. All experimental work has been complemented by density functional theory that provides detailed insights into the thermodynamics of the ring-open and closed forms, the nature of their excited states, and the reactivity of their neutral as well as ionized species in different electronic configurations. The particular diarylethene systems described herein could serve in multifunctional (logic) devices operated by different stimuli (inputs) and may pave the way to converting light into electrical energy via photoinduced “pumping” of redox-active meta-stable states.Keywords
This publication has 75 references indexed in Scilit:
- Bisarylindenols: fixation of conformation leads to exceptional properties of photochromism based on 6π-electrocyclizationChemical Communications, 2012
- Mechanism and Fluorescence Application of Electrochromism in Photochromic DithienylcyclopenteneOrganic Letters, 2012
- Molecular switches as photocontrollable “smart” receptorsChemical Society Reviews, 2012
- Photoswitchable mixed valenceChemical Society Reviews, 2012
- Using light and a molecular switch to ‘lock’ and ‘unlock’ the Diels–Alder reactionOrganic & Biomolecular Chemistry, 2012
- An Organic Optical Transistor Operated under Ambient ConditionsAngewandte Chemie-International Edition, 2011
- Intramolecular Hydrogen Bonding in a Triangular Dithiazolyl‐Azaindole for Efficient Photoreactivity in Polar and Nonpolar SolventsEuropean Journal of Organic Chemistry, 2011
- All-Photonic Multifunctional Molecular Logic DeviceJournal of the American Chemical Society, 2011
- Photochromic Organometallics with a Dithienylethene (DTE) Bridge, [Y-CC-DTE-CC-Y] (Y={MCp*(dppe)}): Photoswitchable Molecular Wire (M=Fe) versus Dual Photo‐ and Electrochromism (M=Ru)Chemistry – A European Journal, 2010
- Stereochemistry of Electrocyclic ReactionsJournal of the American Chemical Society, 1965