A kind of z-selective ruthenium carbene olefin metathesis catalyst and its preparation method and application

Abstract

The invention discloses a Z-selective ruthenium carbene olefin metathesis catalyst. The catalyst utilizes the strong electron-pulling characteristics of bromine atoms to improve the reactivity of the catalyst; the addition of bromine atoms also increases the steric hindrance of the whole ligand, improving The selectivity of the catalyst is improved; the large steric hindrance makes the complex have a triangular bipyramidal coordination structure close to the intermediate transition state, which improves the catalytic activity of the catalyst. The catalyst also improves the stability and temperature resistance of the catalyst by inhibiting the nucleophilic addition reaction of the sulfur atom to the benzylidene carbene carbon. The invention also discloses a preparation method of the catalyst, which has simple steps, mild reaction conditions, and the obtained catalyst has excellent thermal stability. The invention also discloses the application of the catalyst in catalyzing the ruthenium carbene olefin metathesis reaction to prepare Z-type olefin products. The catalyst catalyzes the olefin reaction to obtain a cis-type product with a specific configuration, and has high catalytic activity, high selectivity, and product yield. high feature.

Description

technical field [0001] The invention belongs to the field of transition metal organic catalysts, and relates to a Z-selective ruthenium carbene olefin metathesis catalyst and its preparation method and application. Background technique [0002] Olefins with Z-structure have a wide range of applications in the fields of chemistry, biology, and medicine. They need to be prepared by fast, efficient and stereoselective catalytic reactions, and the key to catalytic reactions is catalysts. Many natural open-chain compounds (such as oleic acid, linolenic acid), natural macrocyclic compounds (such as civetone, etc.), and some substances that are said to have anticancer activity contain Z-alkene structures, but traditional alkenes Metathesis catalysts often obtain a high proportion of E-type structure olefins in the cross-metathesis reaction (CM) of open-chain olefins and the metathesis reaction (RCM) of ring-closing olefins that form macrocycles. Therefore, how to reshape the catal...

AI Technical Summary

Problems solved by technology

The 1,8-naphthalene dimercapto-chelated catalysts found in our subsequent studies have very high Z-selectivity but low catalytic activity

[0004] As can be seen from the above, the prior art has the following deficiencies: although the research on Z-selective olefin metathesis catalysts has achieved some results, it is still found that there are general rules to follow; there are fewer types of such catalysts, and the reported catalysts Selectivity and activity need to be further improved

However, the activity and Z-selectivity of ruthenium carbene catalysts with disulfide chelating ligands still need to be further optimized.

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