Syntheses and reactivities of new bis(imido)Mo(VI) complexes of hydrotris(3,5-dimethyl-1-pyrazolyl)borate and X-ray molecular structures of [{HB(3,5-Me2C3N2H)(3)}Mo(Nmes)(2)X] (X = Cl or OH; mes=2,4,6-trimethylphenyl)

摘要

A chloride substitution reaction of a bis(imido) molybdenum(VI) complex, [Mo(Nmes)(2)Cl-2(dme)] (dme = 1,2-dimethoxyethane) with KTp* (Tp* = hydrotris(3,5-dimethyl-1-pyrazole)borate) in THE resulted in [Tp*Mo(Nmes)(2)Cl] I in good yield. The analogous methylated complex [Tp*Mo(Nmes)(2)(CH3)] 2 was formed by reaction of I with 1 equiv. of CH3MgCl in THF, while [Tp*Mo(Nmes)(2)(OH)] 3 was conveniently produced from 2 in the presence of wet methanol under aerobic conditions. The complexes were characterized by H-1 NMR and IR spectroscopy. The molecular structures of complexes of I and 3 have been determined by X-ray single crystal analyses. The crystal structures of the complexes show that the three nitrogen atoms of Tp* are not equidistant from the respective Mo(VI) centers. Each Mo(VI) centre of I and 3 is in a distorted octahedral coordination geometry with a facially co-ordinated Tp* and two Nines ligands. The complexes of I and 3 contain linear imido ligands (C) 2002 Elsevier Science Ltd. All rights reserved. [References: 30]