Synthesis and photochromism of aryl(heteroaryl)- and diheteroarylethenes – coumarin derivatives

Abstract

In this review, we discuss the synthesis and photochromism of aryl(heteroaryl)- and diheteroarylethenes, containing pyrane ring of coumarin as part of the photosensitive hexatriene system or bearing a coumarin unit as a substituent outside of hexatriene. Coumarinylethenes with noncyclic double bond as well as coumarinyl(thienyl)thiazoles, coumarinyl(thienyl)maleic anhydride (or maleimide) derivatives, and 3,4-bis(thiazolyl)coumarins possess both photochromism and fluorescence switching properties upon UV/vis irradiation.

Bumpy Roads Lead to Beautiful Places: The Twists and Turns in Developing a New Class of PN-Heterocycles

“…That initial report hinted that there was a lot that could be learned about this new moiety and begged the question as to whether phosphaquinolinone optoelectronic properties could be modified in a similar fashion as coumarin and carbostyril, two well-known, well-studied chromophores ( Figure 2). [54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69][70][71][72] There is an obvious structural relationship between the latter two structures in Figure 2, where the carbonyl in carbostyril is replaced with an isolobal P(OR)=O group to afford the phosphaquinolinone scaffold. Taking inspiration from the structure-property relationships drawn for the coumarin and carbostyril family of fluorophores, Jeremy set out to perform structure-property relationship studies with substituent groups at two different sites upon the backbone.…”

Coumarin-diene photoswitches for rapid and efficient isomerization with visible light

“…While photoswitchable molecules have been extensively reported 7,10,11 , most tend to be variations on a few major classes such as azobenzenes 12,13 , diarylethenes 14 , spiropyrans 15 , fulgides 16 , stilbenes 14 and hemithioindigos 14 . The high molar absorptivity and photostability of many coumarin chromophores such as 7-diethylaminocoumarin 17 (DEAC), has led to their extensive use as laser dyes 18 and fluorescent probes 19 , but despite their many photochemical applications the use of coumarins as photochromic materials has been rare and limited mostly to spiropyrans 20 and diarylethenes 21 . We have discovered that attaching strongly electron-withdrawing extended -systems on the 3-position of 4-methyl-DEAC yields highly efficient cis-trans alkene photoswitches.…”