Investigation on catalytic activity of Cu-complex immobilized on ModifiedCarbon Dots for Carbon-Carbon Homocoupling Reaction

In this study attempts has been made to prepare modified carbon dots (CDs) with branchpoly (ethyleneimine) (BPEI) from citric acid, as carbon source, in water at ۲۰۰ ͦC, followed byimmobilized different Cu compounds on it and designated as Cu-BPEI-CDs nanocomposites Thenit was used as catalyst for the terminal alkynes homocoupling reaction. The straight approach forthe synthesis some ۱,۳-diynes is the coupling of two terminal alkynes, as expanded by Glayser andHay [۱-۴]. Due to the high abundance, low cost and low toxicity of copper, it has been widelyconsidered as excellent catalyst for the synthesis of ۱, ۳-dieynes. After characterization of theprepared heterogeneous compounds by means of XRD, FTIR, SEM, TEM and XPS, they weretested as catalysts for the oxidative homo-coupling of phenylacetylene, ۴-tertbutylphenylacetylene,۱-ethynyl-۴-flourobenzene and ۱- pent-۱-yn-۳ol. It was found that Cu (I) Iand Cu (I) bipyridene show conversion yields of ۶۷-۱۰۰ % with excellent selectivities (۹۵–۱۰۰).The catalysts were also recovered and used for four runs without significant decrease in catalyticactivities

Keywords:

Carbon Dots , Couper (I) Compounds , C-C Homocoupling , Polyethylene Imine , Citric Acid