63697-00-7Relevant articles and documents
Preparation method for key intermediate of Barnidipine
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Paragraph 0034; 0036-0037, (2019/10/07)
he preparation method of the intermediate is characterized by comprising the following steps: with chiral hydroxy acid as a starting material, the chiral hydroxy acid reacts with isopropanol under the catalysis of lewis acid, then reacts with an acetoacetic acid reagent, and is directly cyclized with m-nitrobenzaldehyde and methyl 3-aminocrotonate in an alcohol solvent, then crystallization is performed in a low temperature environment for realizing chiral resolution, hydrolysis is performed by sodium hydroxide, and then acidization is performed by hydrochloric acid to obtain a product. the intermediate is characterized by being prepared by the following steps: with chiral hydroxy acid as a starting material,the chiral hydroxy acid reacts with isopropanol under the catalysis of lewis acid, then reacts with an acetoacetic acid reagent, and is directly cyclized with m-nitrobenzaldehyde and methyl 3-aminocrotonate in an alcohol solvent, crystallization and chiral resolution are realized in a low temperature environment, hydrolysis is performed by sodium hydroxide, and then acidization is performed by hydrochloric acid to obtain a product. The preparation method disclosed by the invention has the advantages that the preparation technology is simple, the resolution is easy, the product yield is high, the optical purity is good, the quality is stable, and the large-scale industrial production is easy.
Preparation method of (R)-(+)-2-p-hydroxyl phenoxyl propionic acid
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Paragraph 0049; 0050, (2018/11/22)
The invention relates to a preparation method of (R)-(+)-2-p-hydroxyl phenoxyl propionic acid. The method comprises the following steps of taking (S)-(-)-lactic acid as a raw material, and performingthree-step reaction, i.e., esterification, nucleophilic substitution and hydrolysis to obtain a target compound. A synthetic process for the (R)-(+)-2-p-hydroxyl phenoxyl propionic acid is further optimized, and the optimum reaction condition and reagent are screened. According to the preparation method designed in the invention, the reaction steps are shortened, and the yield and optical purity of the (R)-(+)-2-p-hydroxyl phenoxyl propionic acid are improved.
Organosoluble zirconium phosphonate nanocomposites and their supported chiral ruthenium catalysts: The first example of homogenization of inorganic-supported catalyst in asymmetric hydrogenation
Chen, Taotao,Ma, Xuebing,Wang, Xiaojia,Wang, Qiang,Zhou, Jinqin,Tang, Qian
experimental part, p. 3325 - 3335 (2011/05/13)
In this article, we report the synthesis, structure, morphologies, and asymmetric catalytic properties of a series of novel organosoluble zirconium phosphonate nanocomposites and their supported chiral ruthenium catalysts, which have a good organosolubility (0.1-0.5 g mL-1) in various solvents and mesoporous, filiform, and layered structures. Due to the organosoluble properties in various organic solvents, the first homogenization of zirconium phosphonate-supported catalyst was realized in the field of catalysis. In the asymmetric hydrogenation of substituted α-ketoesters, enantioselectivities (74.3-84.7% ee) and isolated yields (86.7-93.6%) were higher than the corresponding homogeneous Ru(p-cymene)(S-BINAP)Cl2 due to the confinement effect caused by the remaining mesopores in the backbone of the zirconium phosphonate. After completing the reaction, the supported catalyst can be readily recovered in quantitative yield by adding cyclohexane and centrifugation, and reused for five consecutive runs without significant loss in catalytic activity.
