Enantioselective Ullmann Reaction Catalyzed by Palladium Carbene Functionalized 2D Coordination Polymer

The Ullmann coupling reaction is one of the most beneficial processes for the preparation of binary compounds [1, 2]. In this report, a heterogeneous chiral palladium catalyst has been applied in the Ullmann coupling reaction. In this approach, a 2D coordination polymer of zinc-containing ditopic imidazolium-based dicarboxylate ligands attached to the palladium through a palladium-carbene bond (Scheme 1). The structure of the catalyst was characterized by Fourier transform infrared spectroscopy, X-ray powder diffraction, and 1H NMR spectroscopy after digestion in an alkaline solution. The structure of the chiral biphenyl was confirmed by 1H NMR spectroscopy.

Keywords:

Ullman , Heterogeneous , Catalyst , Chiral , Coupling