Method for preparing propiolic acid compounds

Abstract

The invention discloses a method for preparing propiolic acid compounds. An ionic type iron (III) complex containing monoimide functionalized imidazolium cations is taken as the single-component catalyst, carbon dioxide is taken as the carboxylation reagent, and various propiolic acid compounds are prepared through carboxylation reaction of terminal alkyne under normal pressure. The terminal alkyne substrate relates to phenylacetylene, substituted phenylacetylene, heterocyclic aryne, aromatic diyne or aliphatic series terminal alkyne. The method for preparing the propiolic acid compounds through carboxylation reaction of terminal alkyne and carbon dioxide under the catalysis of the iron-based catalyst is provided for the first time. Compared with the prior art, the method has the advantages that the catalyst is more environmentally friendly, synthesis is easier, reaction conditions are mild, and catalytic activity and functional group tolerance are unchanged or improved.

Description

technical field [0001] The invention belongs to the technical field of preparation of organic compounds, and in particular relates to a preparation method of propiolic acid compounds. Background technique [0002] Propiolic acid compounds are important intermediates in the synthesis of fine chemicals and pharmaceutical molecules, such as the synthesis of heterocyclic compounds such as coumarin and flavonoids through cycloaddition and other reactions; in addition, they are also used in the preparation of substituted alkynes by decarboxylation cross-coupling reactions One of the important raw materials, so the synthesis of propiolic acid compounds has been widely concerned (see: Gooβen, L.J., Rodríguez, N., Manjolinho F., Langea, P.P., Adv.Synth.Catal ., 2010, 352, 2913). In the prior art, the method for synthesizing propiolic acid compounds is mainly the oxidative carboxylation reaction of alkynes, using formaldehyde or carbon monoxide as the carboxylation reagent, but forma...

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Problems solved by technology

In the prior art, the method for synthesizing propiolic acid compounds is mainly the oxidative carboxylation reaction of alkynes, using formaldehyde or carbon monoxide as the carboxylation reagent, but formaldehyde or carbon monoxide has the disadvantages of expensive price, high toxicity and inconvenient operation. Therefore, the application of these methods is limited

It has been reported in the literature that propiolic acid compounds can be prepared using metal-organic reagents (such as Grignard reagents), but metal-organic reagents have the disadvantages of being expensive, sensitive to air, and difficult to handle. Therefore, a new method for developing synthetic propiolic acid compounds is with good application prospects

[0003] In recent years, many preparation methods avoid the use of expensive metal-organic reagents, such as (1,10-phenanthroline)-bis(triarylphosphine) copper nitrate as a catalyst, which can realize various aliphatic terminal alkynes and aromatic The carboxylation reaction of terminal alkynes, but for aromatic terminal alkynes, it needs to be carried out under the condition of five atmospheres; N , N , N'N' - Under the condition of tetramethylethylenediamine as the ligand, the carboxylation reaction of terminal alkynes and carbon dioxide catalyzed by cuprous chloride can be realized. The reaction conditions are mild and can be completed at room temperature and normal pressure. The aromatic terminal alkyne has almost no activity, and the carboxylation of the electron-deficient aromatic terminal alkyne can be achieved only when the ligand is changed to nitrogen heterocyclic carbene and the amount of catalyst is increased at the same time, but the yield is low, and the practical application significance is not significant. Large; the silver catalyst catalyzed carboxylation reaction system of terminal alkyne and carbon dioxide does not need to add ligands, the amount of catalyst is not high, but the reaction system still needs two atmospheres of carbon dioxide, and the activity of most substrates is low; rare earth The compound-catalyzed carboxylation of terminal alkynes with carbon dioxide has relatively mild conditions, but the substrates are limited to common terminal alkynes, and terminal alkynes containing aldehyde groups, cyano groups, etc. that are sensitive to metal organic reagents (such as Grignard reagents, etc.) are not involved. Arrived, and rare earth compounds are more expensive, sensitive to air, not easy to handle

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