Method for preparing 6-hydroxy-2(1H)-quinolone in ionic liquid by using one-pot method

Abstract

The invention discloses a method for preparing 6-hydroxy-2(1H)-quinolone in ionic liquid by using a one-pot method. The invention synthesizes the 6-hydroxy-2(1H)-quinolone by through bromination, acidation and intramolecular Heck reaction of p-methoxy aniline and acryloyl chloride as raw materials in the ionic liquid by using the one-pot method. The method has simple synthesis line, low product cost and high yield, is environmental friendly and is easy to realize industrial production.

Description

technical field [0001] The present invention relates to 6-hydroxyl-2( 1H The preparation method of )-quinolinone, be specifically related to a kind of one-pot method preparation 6-hydroxyl-2( 1H )-quinolinone method. Background technique [0002] 6-Hydroxy-2(1H)-quinolinone and its derivatives have antibacterial and positive inotropic activity, and are important intermediates in the synthesis of drugs for strengthening the heart, lowering blood pressure, treating diabetes, promoting cerebral circulation, anti-asthma and anti-ulcer. Since the 1980s, the research on the synthesis of cardiovascular drugs from these compounds has attracted people's attention, and many new drugs synthesized from them have entered the stage of clinical trials. Therefore, it is of great significance to study the synthesis and application of this kind of compounds. [0003] 6-Hydroxy-2(1 H )-quinolinone synthetic method mainly contains: [0004] (1) With 6-methoxyquinoline as starting material...

AI Technical Summary

Problems solved by technology

[0006] (3) Gattermann used electrochemical method to reduce the nitro group of 2-nitro-5-hydroxycinnamic acid to amino group, and then carried out ring-forming reaction. The method is limited by production cost, production equipment and production scale, so it is difficult to promote and apply in our country at present

[0007] (4) Richard started from N-oxidized-6-methoxyquinoline, chlorination, methoxylation and acidification , the reaction process involves a complicated separation process, and the product yield is low

The traditional Heck reaction usually uses Pd(0) as a catalyst, which requires an equal or multiple amount of ligand, and the reaction is sensitive to air and water, and needs to be carried out under the protection of an inert gas, which increases the complexity of the operation and affects The Industrial Application of Heck Reaction

Homogeneous catalysts such as PdCl2 or Pd(OAc)2 can effectively catalyze the Heck reaction, but they are difficult to separate and recycle from the reaction system. It is easy to generate palladium black in the medium, which not only reduces the activity of the catalyst, but also contaminates the reaction product.