Carbonyl group coordination preferences in square-planar NiII and PdII complexes of pentadentate ligands by electron-withdrawing/donating substituents
作者:Jianlin Han、José Luis Aceña、Nobuhiro Yasuda、Hidehiro Uekusa、Taizo Ono、Vadim A. Soloshonok、Karel D. Klika
DOI:10.1016/j.ica.2015.04.029
日期:2015.7
A series of chirally switchable Ni-II and Pd-II complexes were synthesized and fully characterized by X-ray crystallography and additionally by NMR. It was found that control of the stereochemical preference between (S*,S*) and (S*,R*) diastereomers by substituent modification of the ligand sidearms was possible in the process of crystallization with the preferred coordination of the sidearms generally consistent with expectations based on the electron-donating or -withdrawing properties of the sidearm substituent groups. There were however, quite interesting and unanticipated exceptions counter to chemical intuition and it seems that only for complexes with ortho substituents are strong preferences for the coordination manner necessarily displayed in the solid state based on the electron-withdrawing or -donating properties of the substituents. (C) 2015 Elsevier B.V. All rights reserved.