Palladium N-heterocyclic carbene catalysts for synthesis of diaryl ethers

Novel functionalized 1,3-dialkylimidazolinium (LH) salts as precursors for N-heterocyclic carbenes (NHCs) have been prepared and successfully applied in the palladium-catalyzed synthesis of diaryl ethers and arylation of benzaldehydes. An efficient catalyst system was prepared in situ from Pd(OAc)2, 1,3-dialkylimidazolinium bromides (LHBr), and NaH. © Georg Thieme Verlag Stuttgart