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ChemicalBook CAS DataBase List 5,6-Dichloronicotinic acid
41667-95-2

5,6-Dichloronicotinic acid synthesis

2synthesis methods
-

Yield:41667-95-2 91%

Reaction Conditions:

Stage #1: ethyl 5,6-dichloronicotinatewith sodium hydroxide in tetrahydrofuran;methanol;water at 20; for 0.5 h;
Stage #2: with hydrogenchloride in water;

Steps:

33.1 Preparation of 5,6-dichloronicotinic acid

A mixture of ethyl 5,6-dichloronicotinate (1.0 g, 4.5 mmol) and aqueous NaOH (2 N, 6.75 mL, 13.5 mmol) in a mixed solvents of THF/MeOH/water (50 mL, 4/1/1) was stirred at room temperature for 0.5 h.
After concentration, the mixture was acidified with 2 N HCl to pH around 2.
The resulting mixture was extracted with ether (30 mL*3).
The organic layer was washed with water (50 mL*3), dried over Na2SO4, and concentrated to afford 5,6-dichloronicotinic acid (800 mg, 91% yield) as a white solid. LCMS (ESI) m/z: 192.0 [M+H]+.

References:

US2013/317000,2013,A1 Location in patent:Paragraph 0368-0369

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