Electrochemical Synthesis of 5‐Benzylidenebarbiturate Derivatives and Their Application as Colorimetric Cyanide Probe

Abstract

Abstract A highly efficient, fast, catalyst‐free, and atom economical method was developed for the synthesis of 5‐benzylidenebarbiturates. Thus, reacting barbituric acid and aldehydes in water as a green solvent under electrochemical conditions afforded the synthesis of the target compounds in six minutes and in highly pure forms. The effects of solvent, reaction time, temperature, electrolyte, and electrode material were studied to optimize the reaction conditions. The scope of the reaction was broadened by the synthesis of 5‐(arylidene)barbiturate derivatives 3 a–3 q using different aldehydes. Calculation of the green chemistry metrics proved the efficiency of the reaction in terms of E‐factor, mass intensity, mass productivity, and reaction mass efficiency. Compound 3 g [5‐(4‐(dimethylamino)benzylidene) barbiturate] was used for the colorimetric detection of cyanide ion over dynamic linear range 1–25 μM with limit of detection (LOD) of 0.86 μM.

Keywords

• Electrochemical synthesis
• Cyanide
• Barbituric acid
• 5-Benzylidenebarbiturate
• Green chemistry