The novel azacrowned phthalimide 1 has been prepared and its fluorescence properties have been investigated by addition of EtOH and Ag +. The phthalimide 1 showed appreciable solvatofluorochromism; its fluorescence maxima (λ FL) appeared in the wavelength region between 458 (in Et 2O) and 544 nm (in EtOH). In benzene, the phthalimide 1 gave off blue emission (λ FL 466 nm) while it emitted green fluorescence (λ FL 497 nm) upon addition of 250 mM of EtOH. Both the blue and the green emissions were quenched by Ag +. Potential logic operations of the phthalimide 1 were examined using fluorescence outputs at 450 (Out 1) and 515 nm (Out 2) and two input stimuli, EtOH (In 1) and Ag + (In 2). The Out 1 was on in the absence of these inputs while its intensity was reduced (off) by either or both of the inputs to serve as a NOR operator. The Out 2 was off without the inputs; in contrast, the intensity of Out 2 was enhanced (on) by In 1. The enhanced Out 2 was switched off by In 2. The Out 2, thus, corresponds to an INHIBIT operation responding to the input signals. The crowned phthalimide 1 mimics a two-input-two-output combinational logic gate with a single fluorophore and a single ion-sensing unit.
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