A blue emissive bis(amidoquinoline) ligand (L, see below) was employed to prepare a copper(I) iodide complex via various reaction conditions. The recrystallization via the ether vapor diffusion afforded an orange emissive 2-D coordination polymer {[(Cu₂I₂)L₂]^.2DMSO}_n (1, see below) linked by Cu₂I₂ clusters as a thermodynamic product. Interestingly, the complex 1 was also obtained under the mechanochemical condition in the presence of three drops of CH₃CN and one drop of DMSO for 30 min, as confirmed by comparative PXRD patterns. In the preliminary sensing experiment, 1 shows a selective photoluminescence quenching for cysteine (Cys) over other amino acids in water.