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Abstract
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Silica-grafted n-propyl-diaza-15-crown-5 (SGPDC) with immobilized palladium nanoparticles was found as an efficient heterogeneous
catalytic system for the Heck and Suzuki coupling reactions and satisfied results were obtained. Different derivatives of aryl halides and
alkenes under the Heck reaction were converted to the corresponding products with good efficiency. The presence of electron-donating
groups on the aryl moiety of aryl halide derivatives retarded the reaction and led to the drop of yields. In contrast, higher efficiency was
observed when electron-withdrawing groups were accommodated on the aryl halide. As well as, a variety of bi-phenyl derivatives were
well synthesized by the coupling reaction between aryl halides and aryl boronic acids derivatives via the Suzuki reaction. Reusability of the
catalyst was examined in both Heck and Suzuki reactions under optimized conditions. The catalyst could be recycled several times without
any treatment in its catalytic activity. The TEM image of the catalyst utilized in the Heck reaction after seven times of recyclability
indicates that the morphology and size of the nanoparticles have remained almost intact.
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