Halogenated benzene ring-containing flexible large-steric-hindrance N-heterocyclic carbene palladium complex as well as preparation method and application thereof

Abstract

The invention relates to a halogenated benzene ring-containing flexible large-steric-hindrance N-heterocyclic carbene palladium complex. The complex has the characteristics that (1) acenaphthenyl is used as a skeleton structure, and the metal center can be stabilized by using the excellent electron donating performance and rigid steric hindrance of acenaphthenyl, so that the catalyst is ensured to keep high stability in the presence of air and water vapor; (2) flexible large steric hindrance is introduced into an arylamine part of N-heterocyclic carbene, so that a metal center has certain openness, the structure of an active center can be changed by the metal center under different reaction conditions, and different active species can be generated in situ, so that selective flipping of different carbon (pseudo) halogen bonds can be realized only by adding one catalyst; and (3) the catalyst is wide in substrate adaptability range and has high activity on heterocyclic poly (pseudo) aryl halide, air and water vapor do not need to be isolated in the reaction based on the catalyst, and high reaction activity can be realized under mild reaction conditions.

Description

technical field [0001] The invention belongs to the field of organic synthesis, and in particular relates to a flexible large sterically hindered N-heterocyclic carbene palladium complex containing a halogenated benzene ring, a preparation method and an application thereof. Background technique [0002] Over the past few decades, multiple C Ar -C Ar key and c Ar Compounds with -X bonds have been widely used in the fields of medicine, pesticides and functional materials, and the development of chemoselective synthetic reactions has become an important research work. So far, the palladium-catalyzed Suzuki-Miyaura coupling reaction has been the best choice for constructing C due to its good functional group tolerance and low toxicity. Ar -C Ar key and c Ar - A method for efficient heteroatom bonding. However, when the Suzuki-Miyaura reaction catalyzes multiple (pseudo)halogenated compounds (such as C-I, C-Br, C-Cl, C-OTf bonds), it often faces poor "chemoselectivity", poo...

AI Technical Summary

Problems solved by technology

Although the above-mentioned palladium catalysts containing phosphine ligands showed good chemoselectivity, they were all sensitive to air and moisture, unstable in the solution state, and less reactive with heterocyclic aromatic boronic acids for nitrogen-containing heterocyclic halogenated aromatics. very low

Therefore, the application of the above-mentioned catalysts is limited to a large extent.

Images