Synthesizing Bis(β‐iminoenolate)copper(II) Complexes and Exploring Substitution Dependent Green Catalytic Application for Azide‐Alkyne Cycloaddition Reaction.

Bis(β‐iminoenolate)copper(II) complexes with different substituents (3 a–c) have been prepared and explored the catalytic activity for azide‐alkyne cycloaddition reaction in environmentally benign condition. Copper complexes showed highly efficient catalytic activity and produced regioselective product of 1,4‐disubstituted‐1,2,3‐triazoles in one‐pot three component reaction between benzyl chloride, sodium azide and alkynes at room temperature in water medium. The structure‐activity comparison revealed that copper complex with electron withdrawing fluoro substituent (3 c) exhibited comparatively higher catalytic activity in azide‐alkyne cycloaddition reactions and produced up to 98 % of yield with 12.5 mol % of the catalyst without addition of any other reagent. [ABSTRACT FROM AUTHOR]