Synthetic method of spirocyclic tetronic acid compound key intermediate

Abstract

The invention discloses a synthetic method of a spirocyclic tetronic acid compound key intermediate. The method comprises the following steps of: mixing a substituted phenylacetic acid compound (I) with a compound (II); heating the mixture to 50-150 DEG C; adding a carboxylic acid activation reagent; preserving heat at the temperature 50-150 DEG C and reacting fully; and performing post-treatmentto obtain a spirocyclic tetronic acid compound key intermediate compound (III). The invention has the advantages that: (1) an acylation reaction is completed at one step in the preparation method, the reaction time is short, the raw material utilization ratio is high, and the energy consumption and the environmental pressure are lowered; (2) in the preparation method, the costs of raw materials are low, and an acid-binding agent or a catalyst is not invested additionally; and (3) the preparation method has a simple process, a small quantity of side reactions and high yield, and is suitable for large-scale industrial production.

Description

technical field [0001] The invention relates to the technical field of fine chemicals, in particular to a method for synthesizing key intermediates of spirocyclic quaternary acid compounds. Background technique [0002] As we all know, spiro compounds occupy an important position in medicine and pesticides due to their unique structures and properties. The planes of the two rings of the spiro compound are perpendicular to each other. Under certain conditions, the existence of the chiral axis can form an asymmetric molecule or an asymmetric molecule. For heterocyclic spiro compounds, since most of them contain heteroatoms such as oxygen, sulfur, and nitrogen with strong electronegativity, the intermolecular force is relatively large, which makes it possible to have spiro conjugation, spiro hyperconjugation or anomeric Effects and other special properties that general organic compounds do not have, so it becomes a very good precursor of pharmaceutical and pesticide lead compo...

AI Technical Summary

Problems solved by technology

The problem wherein is: 1. in the process of preparing acid chloride, it is necessary to carry out distillation after substituted phenylacetic acid and acid chloride reagent for a long time under reflux reaction, the energy consumption is higher, and the acid chloride reagent needs to be excessive, and it will become more dangerous after applying mechanically for a certain number of times. scrap

2. Acid-binding agents such as triethylamine need to be used in the acylation process, which will generate a large amount of waste water and increase environmental costs, or use more expensive catalysts such as DMAP, etc., which will increase the cost of raw materials, which is not conducive to industrial production

3. The total yield of the two-step reaction is not high, and it is not conducive to industrial production

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