Faculty Sponsor's Department(s):
Donor–acceptor Stenhouse adducts (DASAs) are photochromic molecules that respond to visible light and have a wide range of applications in various fields including drug delivery and chemical sensing. However, photoswitching is highly solvent-dependent and DASAs are prone to decomposition, limiting their application. The mechanism for the formation of DASAs has been heavily studied and is well understood, giving rise to chemical sensing applications and further use as a photoswitch. The mechanism of decomposition upon exposure to light and heat is unknown. In this work, we explore a new possible decomposition pathway of DASAs, which undergoes a retro-DASA reaction, resulting in the reformation of the furan adduct. We employ time 1H NMR solution experiments to study the decomposition kinetics of DASA under different solvent conditions including temperature, solvent polarity, and concentration. The discovery of this novel decomposition pathway of DASAs will aid in better understanding the reactivity of DASA under heat and light, as well as new applications. Further work will be to study this decomposition pathway in polymer matrices. This work will pave the way for the design of DASAs on polymers to develop a catch and release system for amines, thus overcoming the limitations of current chemical sensing applications and possibly further applications in novel synthesis approaches.