Chiral N-heterocyclic carbene catalyst as well as preparation method and application thereof

Abstract

The invention discloses a chiral N-heterocyclic carbene catalyst as well as a preparation method and application thereof, and belongs to the technical field of organic chemistry. The preparation method of the chiral N-heterocyclic carbene catalyst specifically comprises the following steps: adding N-bromo-succinimide and p-toluenesulfonic acid into a round-bottom flask, dissolving the N-bromo-succinimide and p-toluenesulfonic acid with DCM, adding 1eq of cycloheptanone 1, and reacting at room temperature overnight; after the reaction is completed, concentrating and purifying the reactant to obtain alpha-bromo-cycloheptanone 2; then weighing 1g of montmorillonite, 10mmol of p-methylaniline and 40mmol of phenylacetylene, carrying out solvent-free reaction at 140 DEG C for 8 hours, cooling the reaction product to room temperature, filtering the reaction product, washing the reaction product with diethyl ether, collecting filtrate, concentrating and purifying the filtrate to obtain a compound 5, carrying out asymmetric hydrogenation reduction on the compound 5, and carrying out multi-step reaction on the compound 5 and alpha-bromo-cycloheptanone 2 to synthesize a target compound 7. The method is high in operability, novel in synthetic route and high in yield. The method can be successfully applied to the amide far-end C (sp3)-H activation tandem cyclization reaction, realizes asymmetric catalysis, and has a wide market application prospect.

Description

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AI Technical Summary

Benefits of technology

The technical effect of this new type of catalyst described by this patented method can be improved efficiency or productivity compared to previous methods while also being more effective at producing certain types of chemical compounds that could potentially replace existing ones like phosgene.

Problems solved by technology

This patented technical problem addressed in this patents relates to improving the performance of certain chemical compounds that use specific ring structures called heterocycles or other groups attached to them (such as nitrogen) due to their ability to participate effectively during various processes such as oxidation/degrading redox reactions.

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