Preparation method of (22E, 24R)-3alpha, 5-cyclo-5alpha-ergosta-7, 22-diene-6-ketone

Abstract

The invention discloses a preparation method of (22E, 24R)-3alpha, 5-cyclo-5alpha-ergosta-7, 22-diene-6-ketone, which belongs to the field of chemical synthesis, and comprises the following steps: 1) by taking ergosterol as a starting raw material and triethylamine as an acid-binding agent, carrying out methylsulfonylation, water addition and phase separation to obtain an organic phase which is a butanone solution of a first-step product, and directly carrying out next-step reaction; 2) adding water and potassium bicarbonate into the butanone solution obtained in the first-step reaction, carrying out heating reaction, and carrying out phase-splitting water removal to obtain a butanone solution of a second-step product; and 3) oxidizing the butanone solution of the product in the second step by using an oxidant potassium osmate and a co-oxidant tert-butyl hydroperoxide to prepare (22E, 24R)-3 alpha, 5-cyclo-5 alpha-ergosta-7, 22-diene-6-ketone. Compared with a traditional CrO3 / pyridine and MnO2 / chloroform oxidation method, the method has the advantages that a heavy metal oxidizing agent which causes serious pollution to the environment and is high in recovery cost is not used, the reaction condition is mild, the yield is high, the aftertreatment is simple, the next-step reaction can be carried out without refining, and the like, and the method is suitable for industrial production.

Description

Technical field [0001] The present invention belongs to the preparation of plant growth regulators, and in particular, the preparation method of (22E, 24R) -3α, 5-ring-5α-wheat-7,22-diene-6-ketone is involved. Background technique [0002] 24-表 内 内 is a broad-spectrum-efficient plant growth regulator. It was previously found in 1970 in 1970, also known as a rapesein, also known as a napus. 24-clamp tslactone in promoting the production of crop yields and improving the neutral targeting of other plant growth regulators. It is not only a physiological function of growthin, cytokinin, and has improved photosynthesis, regulating nutrient distribution, promoting stem carbohydrate to seed transport, improving crops to external unfavorable factors, promoting plant weaknesses. Growth capacity, etc. Function, therefore, it has extremely widely available availability and practicality. [0003] (22E, 24R) -3α, 5-ring-5α-Wheat-7,22-diene-6-ketone is an intermediate for preparing 24-histone t...

AI Technical Summary

Problems solved by technology

Due to the use of chromium trioxide / pyridine oxidation system, a large amount of waste liquid and solid waste containing heavy metal ions will be produced, which will seriously pollute the environment;

[0006] (2) McMorris et al. improved the synthesis method of (22E, 24R)-3α, 5-ring-5α-ergosta-7, 22-dien-6-one in 1993 (McMorris T.C., Patil, J. Org.Chem.1993,58,2338.), is still prepared with chromium trioxide / pyridine oxidation system, resulting in a large amount of waste liquid and solid waste containing heavy metal ions, which seriously pollutes the environment;

Osmium tetroxide is a highly toxic and volatile solid powder, which requires high requirements for operators;

Osmium tetroxide is a highly toxic and volatile solid powder, which requires high requirements for operators;

Although manganese dioxide can be reused after being calcined, a large amount of methanol gas will be released due to the need to introduce air, which may reach the explosion limit after accumulation, posing a certain safety hazard;

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