31255-57-9Relevant articles and documents
Preparation method of loratadine intermediate 3-[2-(3-chlorphenyl) ethyl]-2-pyridinecarbonitrile
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, (2022/01/20)
The invention provides a preparation method as shown in a formula I and a preparation method of 3-[2-(3-chlorphenyl) ethyl]-2-pyridinecarbonitrile. The invention provides a novel method for preparing a loratadine intermediate.
Preparation method of loratadine
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Paragraph 0029; 0049-0051, (2021/02/10)
The invention provides a preparation method of loratadine. The method comprises the following steps: taking 2-cyano-3-methylpyridine as a raw material, and carrying out Ritter reaction, m-chlorobenzylchloride condensation, POCl3 deprotection group, Grignard reaction, cyclization and ethyl chloroformate substitution to obtain 4(8-chlorine-5, 6-dihydro-11H-benzo-[5, 6]cycloheptano[1, 2-b]pyridine-11-subunit)-1-piperidine carboxylic acid ethyl ester. According to the invention, a post-treatment process is innovated, and a new cyclization system is adopted to catalyze the reaction, so that the use of high-cost and high-toxicity strong acid is avoided, and a milder and more economical synthesis method is provided for industrial production.
A 3 - [2 - (3 - chlorophenyl) ethyl] - 2 - pyridine carbonitrile preparation method (by machine translation)
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Paragraph 0026; 0027; 0028, (2018/03/24)
The invention discloses a 3 - [2 - (3 - chlorophenyl) ethyl] - 2 - pyridine carbonitrile (I) of the preparation method. The method in order to 2 - cyano - 3 - methylpyridine and 3 - chlorobenzaldehyde as the starting material, first in an appropriate solvent and condensation reaction under basic conditions shall be 3 - [2 - (3 - chlorophenyl) vinyl] - 2 - pyridine carbonitrile, the intermediate and then the catalytic hydrogenation reaction to obtain 3 - [2 - (3 - chlorophenyl) ethyl] - 2 - pyridine carbonitrile (I); . (by machine translation)