Multiphoton-gated cycloreversion reaction of a photochromic 1,2-bis(thiazolyl) perfluorocyclopentene diarylethene derivative

► A 1,2-bis(thiazolyl) diarylethene for multiphoton-gated photochromism. ► Low cycloreversion quantum yield (1.3 × 10−3) under continuous excitation. ► Time-resolved transient spectroscopy measurements reveal a nonlinear behavior. ► Cycloreversion quantum yield: ca. ×400 up when excited by picosecond laser pulse. ► Enhancement due to stepwise two-photon absorption involving S1 and a higher Sn state.