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ChemicalBook CAS DataBase List 4,6-Dichloronicotinic acid
73027-79-9

4,6-Dichloronicotinic acid synthesis

13synthesis methods
4,6-Dichloronicotinic acid can be used as organic synthesis intermediates and pharmaceutical intermediates, mainly in laboratory research and development processes and chemical production processes. It can be synthesized by the hydrolysis of Sodium hydroxide and 4,6-dichloronicotinic acid ethyl ester.
40296-46-6 Synthesis
Ethyl 4,6-dichloronicotinate

40296-46-6
321 suppliers
$6.00/1g

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Yield:73027-79-9 96%

Reaction Conditions:

Stage #1: ethyl 4,6-dichloronicotinatewith sodium hydroxide;water in tetrahydrofuran;methanol; for 0.5 h;
Stage #2: with hydrogenchloride in tetrahydrofuran;methanol;water; pH=2;

Steps:

9.B

Sodium hydroxide (40 mL, 6.25 M solution) was added to a stirred solution of 4,6-dichloronicotinic acid ethyl ester (22) (25.95 g, 118 mmol) in 4:1:1 THF:MeOH:water (600 mL). After 30 minutes, the reaction mixture was acidified to pH 2 with concentrated HCl, diluted with 1:1 EtOAc:Et2O and washed with water and brine. The organic layer was dried (Na2SO4) and concentrated. The resulting off-white solid was twice concentrated from toluene to give the desired product (23) as a white solid (21.73 g, 96%).

References:

US2005/49419,2005,A1 Location in patent:Page/Page column 24

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