Mechanosynthesis of Second‐Sphere Coordination Salts and Chelating Complexes: Structures, Reversible Transformations, and Nitroaromatic Explosives Sensing

We have investigated the mechanosynthesis of a series of second‐sphere salts, guest⊂[H 2 L] 2+ · [MCl 4 ] 2– [L = N , N′ ‐dibenzyl‐(±)‐ trans ‐1,2‐diaminocyclohexane], and the reversible transformations to their chelating coordination complexes [MCl 2 (L)] through dehydrochlorination reactions. The second‐sphere salts and their corresponding coordination complexes show different solid‐state fluorescence spectra. The complex ZnCl 2 (L) ( 2′ ) acts as a sensor for the highly sensitive detection of nitroaromatic compounds through fluorescence quenching.