title: Molecular logic gates and switches based on 1,3,4-oxadiazoles triggered by metal ions.
abstract: Organic molecular devices for information processing applications are highly useful building blocks for constructing molecular-level machines. The development of "intelligent" molecules capable of performing logic operations would enable molecular-level devices and machines to be created. We designed a series of 2,5-diaryl-1,3,4-oxadiazoles bearing a 2-(para-substituted)phenyl and a 5-(o-pyridyl) group (substituent X=NMe(2), OEt, Me, H, and Cl; 1a-e) that form a bidentate chelating environment for metal ions. These compounds showed fluorescence response profiles varying in both emission intensity and wavelength toward the tested metal ions Ni(2+), Cu(2+), Zn(2+), Cd(2+), Hg(2+), and Pb(2+) and the responses were dependent on the substituent X, with those of 1d being the most substantial. The 1,3,4-oxadiazole O or N atom and pyridine N atom were identified as metal-chelating sites. The fluorescence responses of 1d upon metal chelation were employed for developing truth tables for OR, NOR, INHIBIT, and EnNOR logic gates as well as "ON-OFF-ON" and "OFF-ON-OFF" fluorescent switches in a single 1,3,4-oxadiazole molecular system.
authors.affiliation: Department of Chemistry, College of Chemistry and Chemical Engineering and the MOE Key Laboratory of Analytical Sciences, Xiamen University, Xiamen 361005, China.
authors.forename: Ai-Fang
authors.initials: AF
authors.lastname: Li
authors.forename: Yi-Bin
authors.initials: YB
authors.lastname: Ruan
authors.forename: Qian-Qian
authors.initials: QQ
authors.lastname: Jiang
authors.forename: Wen-Bin
authors.initials: WB
authors.lastname: He
authors.forename: Yun-Bao
authors.initials: YB
authors.lastname: Jiang