1975-50-4Relevant articles and documents
Preparation of 2-arylindole-4-carboxylic amide derivatives
Kuethe, Jeffrey T.,Davies, Ian W.
, p. 11381 - 11390 (2006)
A practical, highly efficient protocol has been developed for the synthesis of functionalized 2-arylindole-4-carboxylic amide derivatives. Commercially available methyl 2-methyl-3-nitrobenzoate gave substituted nitrostyrene benzoic acids by reaction with aromatic aldehydes in the presence of DBU in DMSO. Conversion of these products to the desired amides was followed by Pd-catalyzed reductive cyclization employing carbon monoxide as the terminal reductant to provide the 2-arylindole-4-carboxylic amide derivatives in excellent overall yield for the simple three-step sequence.
Preparation method of 3-nitro-2-methylbenzoic acid
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Paragraph 0023-0038, (2020/07/15)
The invention discloses a preparation method of 3-nitro-2-methylbenzoic acid. The preparation method is characterized by comprising the following steps: (1) oxidizing 3-nitro-o-xylene into 3-nitro-2-methylbenzoic acid in an acidic organic solvent in the presence of a catalyst and an initiator by using oxygen as an oxidant; (2) after the reaction is finished, cooling, crystallizing and filtering toobtain a 3-nitro-2-methylbenzoic acid crude product; (3) re-crystallizing the 3-nitro-2-methylbenzoic acid crude product to obtain 3-nitro-2-methylbenzoic acid; wherein the acidic organic solvent inthe step (1) is acetic acid, propionic acid or a mixture of acetic acid and propionic acid, and the acidic organic solvent contains 0-17% by mass of water. According to the method, an organic acid isused as a solvent, a reaction is carried out under an appropriate reactant concentration, a reaction solution after the reaction is subjected to cooling crystallization to obtain a crude product of 3-nitro-2-methylbenzoic acid, and the crude product is re-crystallized to obtain a product with a purity of 98% or above. The preparation method solves the problems of large amount of waste water and waste salt, difficult post-treatment and serious environmental pollution in the prior art.
2-methyl-3-methoxybenzoyl chloride synthesizing process
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, (2019/03/15)
The invention discloses a 2-methyl-3-methoxybenzoyl chloride synthesizing process. According to the present invention, low-cost o-xylene is used as a starting raw material, the product is synthesizedby using a conventional synthesis method comprising nitrification, esterification, reduction, diazotization, methylation, acyl chlorination and other steps, and the total yield is controlled at more than 65%; the esterification of the intermediate product improves the separation degree of the intermediate; the reaction solvent is added in the diazotization step, such that the process parameters are relatively easy to control, and the purity of the intermediate in the diazotization step is more than 96% so as to provide the guarantee for the quality of the subsequent product; and with the synthesis process, the product quality is stable and reliable, and the cost is low.