Transition metal complex containing asymmetric N-heterocyclic carbene structure as well as preparation method, catalyst system and application of transition metal complex

Abstract

The invention belongs to the field of transition metal complexes, and relates to a transition metal complex containing an asymmetric N-heterocyclic carbene structure, a preparation method of the transition metal complex, a catalyst system and application of the complex and the catalyst system. The general formula of the transition metal complex containing the asymmetric N-heterocyclic carbene structure is NHC. (V = O) XYZ, NHC is an asymmetric N-heterocyclic carbene ligand, and X, Y and Z are the same or different and are independently selected from halogen and / or alkoxy; the preparation method of the complex comprises the following steps: reacting N-heterocyclic carbene hydrochloride with a silver compound to obtain the silver complex containing N-heterocyclic carbene; the obtained silver complex containing the nitrogen heterocyclic carbene reacts with (V = O) XYZ, and the vanadium complex containing the nitrogen heterocyclic carbene ligand is obtained. The transition metal complex containing the asymmetric N-heterocyclic carbene structure has potential application value in the aspects of asymmetric catalysis, product stereoselectivity regulation and control, biomedicine and the like.

Description

technical field [0001] The invention belongs to the field of transition metal complexes, and specifically relates to a transition metal complex containing an asymmetric nitrogen heterocyclic carbene structure, a preparation method thereof, a catalyst system, and applications of the complex and the catalyst system. Background technique [0002] Nitrogen heterocyclic carbene (NHC) is a kind of carbene that is relatively stable at room temperature. The electron-donating conjugation effect of the lone pair of electrons on the two nitrogen atoms connected to the carbene carbon atom to the empty orbital of the carbene carbon atom makes NHC have a strong Nucleophilicity, therefore, NHC has stronger electron donating ability and coordination ability than traditional phosphine ligands, and is widely used in the synthesis of metal complexes, see: Coordination Chemistry Reviews, 2020, 422:213334; ACS Catalysis, 2020 , 10:6862-6869. Among the many complexes containing NHC ligands, the v...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide an asymmetric nitrogen-heterocyclic carbene structure in view of the current situation of the only vanadium complexes containing NHC ligands with symmetrical structures and the difficulty of directly preparing vanadium complexes containing NHC ligands with asymmetric structures. Transition metal complexes and preparation methods thereof do not need to use expensive strong bases (as potassium tert-butoxide) and air-sensitive NHC ligands, and use NHC hydrochlorides that are not sensitive to water and oxygen as raw materials. The silver compound can also be recycled to reduce production costs, and the target product yield and purity are high, which is of great significance to the wide application of the vanadium complex

Images