Magnetically recyclable palladium nanoparticles (Fe₃O₄‐Pd) for oxidative coupling between amides and olefins at room temperature

Abstract

A convenient method for the synthesis of magnetically recyclable palladium nanoparticles (Fe 3 O 4 -Pd) is described. The catalytic application of the Fe 3 O 4 -Pd nanoparticles was explored for the first time in oxidative coupling between amides and olefins. p-Toluenesulfonic acid plays a significant role in the oxidative amidation reaction. The reaction proceeds at room temperature, resulting in (Z)-enamides under ambient air in the absence of co-catalyst and ligand.The superparamagnetic nature of Fe 3 O 4 -Pd facilitates easy, quantitative recovery of the catalyst from a reaction mixture, and it can be reused for up to three consecutive cycles with a slight decrease in catalytic activity.

Ce-catalyzed regioselective synthesis of pyrazoles from 1,2-diols via tandem oxidation and C–C/C–N bond formation

“…So, the present challenge is to develop a simple and efficient catalytic system for the facile synthesis of regioisomerically pure pyrazoles under ligand-free conditions. In line with our continuing interest in metal-catalyzed C–C and C–heteroatom bond-forming reactions under ligand-free conditions, 11 we herein report a straightforward method for the regioselective synthesis of 1,3-di- and 1,3,5-trisubstituted pyrazoles from easily accessible hydrazones and diols by employing inexpensive ceric ammonium nitrate (CAN) as an eco-friendly catalyst under mild conditions.…”