A kind of preparation method of fully substituted thiophene

Abstract

The invention relates to a preparation method of totally-substituted thiophene and belongs to the field of chemical synthesis. The preparation method comprises the following steps: stirring elemental sulfur and a double-molecule alkynyl ketone type compound under the catalysis of an inorganic strong alkali until reaction ends, and separating the obtained mixture to obtain a thiophene product. The method is simple and convenient to operate, easy jn obtaining of raw materials, mild in reaction condition, high in yield, simple and easy in separation of reaction products, low in cost and applicable to industrial production.

Description

technical field [0001] The invention belongs to the technical field of organic synthesis chemistry, and specifically relates to a method for preparing fully substituted thiophenes from elemental sulfur and two molecules of acetylenic ketones. Background technique [0002] Thiophene is an important class of heterocyclic compounds, which are often used in the synthesis of key structural units of biologically active natural products, drugs, and organic conductive materials. The methods that have been developed so far include: Hinsberg synthesis reaction, Gewald synthesis reaction, intramolecular synthesis reaction, multi-component coupling methodology and other multi-step operation reactions. [0003] It is difficult to synthesize all-substituted thiophene derivatives, whether it is industrial production or preparation of thiophene in the laboratory. Fully substituted thiophene derivatives are mostly synthesized by adding substituents to the thiophene ring. This synthesis meth...

AI Technical Summary

Problems solved by technology

Fully substituted thiophene derivatives are mostly synthesized by adding substituents to the thiophene ring. This synthesis method has a long synthetic route and many by-products. Especially at the end, due to the existence of steric hindrance, the reaction conditions are harsh and produce Low rate, many by-products

Therefore, the synthesis of fully substituted thiophene derivatives mostly exists in laboratory research, and industrial transformation is difficult.

[0004] In recent years, it has been reported that organic sulfur compounds or sulfur phosphorus compounds and acetylenic ketones are combined to form fully substituted thiophene derivatives, but because the reaction needs metal compounds such as Pd, Fe, Ru, Mn as catalysts, and sulfur as raw materials It is an organosulfur compound or a sulfur-phosphorus compound with high cost, low yield, many by-products, lack of practical value, difficulty in large-scale industrial production, and shortcomings such as narrow substrate range, long reaction time, complicated reaction steps, and serious environmental pollution.

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