Yield:338758-69-3 89.1%

Reaction Conditions:

with ammonium hydroxide in acetonitrile at -10;

Steps:

2.1 (1) Synthesis of intermediate 3-chloro-5-(trifluoromethyl)pyridine-2-carboxamide:

Add 100 mL of concentrated ammonia water and 50 mL of acetonitrile to a 250 mL three-necked flask, and place it in a low-temperature cooling circulator (-10° C.) to stir and mix evenly.A solution of 60.5 g (50.4%) of 3-chloro-5-(trifluoromethyl)pyridine-2-carbonyl chloride in acetonitrile was transferred to a constant pressure dropping funnel and slowly added dropwise to the flask.After dripping, TLC (developing solvent is V (petroleum ether):V (ethyl acetate)=7:1) monitors the reaction degree of acid chloride in the reaction system, after the reaction of acid chloride is complete, add 50 mL of deionized water, and continue stirring for 15min.After suction filtration, the filter cake was washed three times with 20 mL of deionized water and dried to obtain 26.6 g of a white powdery solid with a yield of 89.1%

References:

CN114805197,2022,A Location in patent:Paragraph 0036-0039