Singlet oxygen‐responsive photorelease of tyramine.

A system capable of photoreleasing tyramine has been developed. The photodonor system consists of an isoindole cage of tyramine and a biscyclometalated Ir(III) complex singlet oxygen (1O2) photosensitizer. Photoirradiation at a wavelength of 365 nm produces tyramine, as evidenced by mass spectrometry and 1H NMR spectroscopy. The photorelease proceeds through two steps involving the formation of a Diels–Alder‐type [2 + 4] cycloadduct of 1O2, followed by the slow and spontaneous decomposition of the adduct into tyramine and 2‐benzoylbenzophenon. [ABSTRACT FROM AUTHOR]