Ultrafast transient absorption spectroscopy of the photodecarbonylation of photo-oxadibenzocyclooctyne (photo-ODIBO)

The ultrafast dynamics of photo-OxaDiBenzocycloOctyne (photo-ODIBO) photo-dissociation was studied using femtosecond transient absorption spectroscopy. Steady-state UV–Vis, time-dependent density functional theory, and 350 nm and 321 nm transient absorption studies are reported. Photo-ODIBO excitation with 321 nm and 350 nm light-induced photodecarbonylation of the cyclopropenone functional group results in the formation of ODIBO. The presence of the photoproduct was confirmed by the results of steady-state photolysis experiments and the observation of absorption signatures of ODIBO in the photo-ODIBO transient absorption spectra. Analysis of the latter revealed the underlying photochemical mechanisms and associated time constants, following excitation of the samples. The dynamics show a multi-exponential decay process, following the dissociation of photo-ODIBO into an excited state of the photoproduct ODIBO within