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.

Luminescent PhotoCORMs: Enabling/Disabling CO Delivery upon Blue Light Irradiation

“…On the other hand, for complex 2 , the lowest energy band 384 nm is attributed to a mixed π–π* transition of the dimethylamine group, together with a MLCT transition. This increases the molar absorptivity relative to 1 and decreases when compared to the free Oxa-Me 2 ligand (ε = 33500 L mol –1 cm –1 ) . A similar redshift and decrease of the molar absorptivity for Oxa-Me 2 complexes was reported by Li and co-workers .…”

“…This increases the molar absorptivity relative to 1 and decreases when compared to the free Oxa-Me 2 ligand (ε = 33500 L mol –1 cm –1 ) . A similar redshift and decrease of the molar absorptivity for Oxa-Me 2 complexes was reported by Li and co-workers . Also, for complex 2 , the second intense band at 318 nm is attributed to a π–π* transition.…”

Photophysical Properties of Luminescent Zinc(II)‒Pyridinyloxadiazole Complexes and their Glassy Self‐Assembly Networks

“…Ligand L o was obtained as white crystals that melt at 149 °C. For the known compounds L m and L p , the data are in good agreement with the literature , . The reaction of zinc(II) acetate with ligands L i in pyridine gave mononuclear pale‐to‐bright yellow microcrystalline complexes with general formula [Zn(L i ) 2 py 2 ] (Scheme ).…”

Metal Complexes of Oxadiazole Ligands: An Overview

“…Therefore, monitoring the emission intensity at 396 nm, upon addition of PPi and S 2- , and their mixture results in an INHIBIT logic gate. In this regard, it is worth mentioning the report form Jiang and co-workers where they prepare different molecular logic gates and switches based on 1,3,4-oxadiazoles triggered by metal ions [52].…”