A Ready-To-Use Fluorescence Probe Of Pd2+ In Water: Novel Tricyclic Heterocyclic Base On 1,3,4-Oxadiazole

A ready-to-use hetero-tricyclic compound, 5,5 '-(furan-2,5-diyl) bis (1,3,4- oxadiazol-2-amine) (5), was synthesized with a good yield; it has an suitable fluorescence characteristic and research founded that it can respond to trace Pd2+ in water at a normal pH range. A fluorescence titration revealed the detection limit for Pd2+ was as low as 3.97 x 10(-9) M. Density-functional theory calculation using Guassian09 implied that the breakage of conjugation and coplanarity of compound 5 led to fluorescence quenching. Compound 5 could be applied as a chemical probe to detect trace amounts of Pd2+ with good accuracy, fast response time, excellent selectivity, and high sensitivity. FT-IR, NMR, and MS were used to characterize the chemical structure of compound 5.