Fig. 3. Top: UV-vis (a) and fluorescence (b) spectral change of E-2a in THF upon irradiation at 365 nm (the final spectrum corresponds to ∼80% formation of 2b. Bottom: the UV-vis (c) and fluorescence (d) spectra of isolated E-2a, 2b, and 2c in THF (1.0 × 10–5 M). Inset: photographs showing the absorption and emission colours and relative intensity of E-2a, 2b, and 2c in THF.
