Determination of cyanide in organic and aqueous environments by NASH reaction

Cyanide selective and sensitive 3,5-dinitrobenzamide based novel nine colorimetric and fluorimetric compounds were synthesized. The compounds' crystallized structures and surface morphologies (2, 4, 5, 7, and 8) were determined by X-ray and ESEM analysis. The cyanide sensing properties were investigated against competing anions such as F−, AcO−, and H2PO4– in organic (DMSO) and aqueous solutions. The compounds exhibit a vivid color change from colorless to blue/purple and pink fluorescence after interacted with cyanide ion. Also, practical applications such as test strips showed that compounds easily change color and emission with cyanide. The structural and electronic properties of the compounds and their complexes formed via deprotonation and addition processes were determined with 1H NMR titration and Density Functional Theory (DFT) and time-dependent DFT (TD-DFT) calculations.