Method for selectively hydrogenating alpha, beta-unsaturated carbonyl compound by cobalt complex

Abstract

The invention provides a method for selectively hydrogenating an alpha, beta-unsaturated carbonyl compound. The method for selectively hydrogenating the alpha, beta-unsaturated carbonyl compound comprises the steps that first, a cobalt metal precursor and a carbene ligand are coordinated in a solution to obtain a cobalt complex, and the cobalt complex selectively enables the alpha, beta-unsaturated carbonyl compound to be reduced into a corresponding saturated carbonyl compound in a hydrogen atmosphere under the activation of an activator. The method for selectively hydrogenating the alpha, beta-unsaturated carbonyl compound has the main advantages that cobalt is used as a catalyst, and metal cobalt is cheap and easy to obtain relative to noble metal such as palladium, ruthenium, osmium, iridium and platinum, and the catalyst cost is greatly reduced; secondly, the carbene ligand used in the method has the advantages of simple structure, low price, strong coordination ability with cobalt atoms compared with a commonly used phosphine ligand; and finally, the addition of the activator can further significantly increase the activity of the cobalt catalyst. The hydrogenation reaction condition is mild, the reaction rate is high, substantially no carbonyl hydrogenation side reaction occurs, and the carbonyl compound can be obtained in a high yield.

Description

technical field [0001] The invention belongs to the fields of fine chemicals and flavors and fragrances, and in particular relates to a method for selectively hydrogenating α, β-unsaturated carbonyl compounds with cobalt complexes. Background technique [0002] α, β-Unsaturated carbonyl compounds can be obtained by aldol condensation reaction. In these compounds, C=C double bond and C=O double bond are conjugated. How to realize the C=C double bond or C=O double bond Selective reduction has always been one of the difficult problems in organic synthesis. In the selective reduction of α, β-unsaturated carbonyl compounds, α, β-unsaturated aldehydes and ketones are more difficult, while the selective reduction of α, β-unsaturated esters and amides is relatively easy. In classical organic synthesis, a Luche reduction is used, in the presence of Lewis acid cerium trichloride, a reducing reagent such as NaBH 4 etc. can realize the selective reduction of the carbonyl group in the ...

AI Technical Summary

Problems solved by technology

But in known technical document at present, mostly adopt precious metal such as palladium, ruthenium, rhodium, iridium, platinum etc. to realize above-mentioned conversion, and catalyst cost is expensive, and economic cost is higher; If can use cheap metals such as cobalt, nickel, iron, copper Realize the selective hydrogenation of C=C double bonds of α, β-unsaturated carbonyl compounds, which can significantly reduce costs and bring better economic benefits

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