A Covalently Supported Pyrimidinylphosphane Palladacycle as a Heterogenized Catalyst for the Suzuki–Miyaura Cross Coupling

Abstract

The amino moiety of an aminopyrimidinyl phosphane allows rapid functionalization of the ligand with a silylated side chain containing a urea linker for catalyst heterogenization. The urea group causes the resulting ligand to undergo spontaneous CH activation at the pyrimidinyl site when reacted with (C₆H₅CN)₂PdCl₂ in CH₂Cl₂. Grafting of the resulting zwitterionic palladacycle complex onto siliceous supports leads to highly active hetereogeneous catalysts for the Suzuki–Miyaura coupling. Leaching tests proved that the catalysts obtained this way are truly heterogeneous.