“…The reported impy compounds display mono-electronic oxidation (generally reversible), characterized by half-wave potential E 1/2 of about 400 mV (versus ferrocene/ferrocenium reference, Fc/Fc + ), as previously reported for impy derivatives and corresponding complexes. [4,26,28,67,111] Many works have been reported concerning the application of different impy products as molecular sensors, [121] for example for the quantification of hydrogen sulphide [122,109,123] and hydrogen polysulphides, [124] sulphur dioxide, [125] hypochlorous acid, [126][127][128] and metal ions such as Cu 2 + , [129] Cd 2 + and Zn 2 + , [130] Hg 2 + . [11] Moreover, impy products have been successfully employed as ratiometric pH-Sensors based on a dual emission pathway [29,30] or as fluorescent pH probes in living cells.…”