Hangzhou Pharmco Co., Ltd

BASIC INFORMATION

Stability: Stable under normal temperatures and pressures.

Storage: Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances.

Quality

Expiry time: 2 years

Specification

USAGE of 2-chloronicotinic acid:

1. The intermediate of the herbicide nicosulfuron and piofluramide.

2. Used as pharmaceutical intermediate, used for manufacturing fuminic acid, fuminic acid, etc.; Pesticide intermediate, used to manufacture nicosulfuron, pifluramide, etc.

Production methods

The preparation methods are as follows.

(1) 3 - methyl pyridine as raw material, the first to react with hydrogen peroxide to generate N - oxygen - 3 - methyl pyridine, and then tied acid agent, in the presence of diisopropyl amine in the solvent and phosphorus oxychloride as the chlorinating agent to ring chloride, 2 - chloro - 5 - methyl pyridine and 2 - chloro - a mixture of 3 - methyl pyridine, crystallization and distillation method of separation technology, can be obtained respectively 2 - chloro - 5 - methyl pyridine and 2 - chloro - 3 - methyl pyridine.Side chain chlorination of 2-chlorine-3-methyl pyridine yields 2-chlorine-3-trichloromethyl pyridine, and further hydrolysis yields 2-chloro-3-pyridine formyl chloride or 2-chloro-3-pyridine carboxylic acid (2-chloro-niacin).

(2) Chlorine is injected into the mixture of phosphorus oxychloride and phosphorus trichloride, and the temperature is controlled at about 60℃. Until the remaining chlorine gas escapes, cool it and add n-oxide niacin in batches to heat the mixture.The reaction took place at 100 ~ 105℃ for 1 ~ 1.5h. After the reaction mixture was transparent, the reaction was stirred for 30min, and the phosphorus trichloride was removed under pressure. The residue was cooled to room temperature, and the finished product was prepared by adding water.

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