Synthesis of palladium complexes derived from imidazolidin-2-ylidene ligands and used for catalytic amination reactions

Abstract

N-Aryl amination and the Buchwald-Hartwig reaction are of great synthetic and industrial interest and scientists accept their usefulness and versatility for obtaining arylamines. In this study Ag-N-heterocyclic carbene complexes were used as trans-metallation reagents for the synthesis of Pd-N-heterocyclic carbene complexes. The new Pd-N-heterocyclic carbene complexes were characterized using elemental analysis and H-1 NMR, C-13 NMR and infrared spectroscopies. The crystal structure of one, namely dichlorobis[1,3-bis(2-methylbenzyl)imidazolidin-2-yliden]palladium(II), is presented. The activity of the Pd(II) complexes in the coupling reaction of anilines or amines with bromobenzene was investigated. These complexes exhibited high catalytic activities in the direct synthesis of triarylamines and secondary amines in a single step. Copyright (C) 2016 John Wiley & Sons, Ltd.