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ChemicalBook CAS DataBase List 2-Picolinic acid
98-98-6

2-Picolinic acid synthesis

11synthesis methods
2-Picolinic acid synthesis: In a 500ml three-necked flask, add 100g of 2-cyanopyridine and 200g of deionized water, then start stirring, heat up to 50°C, add 128.2g of 30% sodium hydroxide to the flask, after adding, add Continue to heat up, react under reflux for 4 hours, then distill water, after 50 g of distilled water, cool the reaction solution to 20°C, add 30% hydrochloric acid, adjust the pH value of the reaction solution to 2.5, then turn on the steam to heat up the water and steam to the kettle When the temperature reaches 120°C, the reaction solution is evaporated to dryness, and the distilled water is completed. Then, 300 g of anhydrous alcohol is added dropwise to the flask to maintain the temperature of the reaction solution at 55°C. After cooling and crystallization, a solid was precipitated, filtered and dried to obtain 106.0 g of 2-picolinic acid with a yield of 89.6%.
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Yield:98-98-6 97%

Reaction Conditions:

with tert-butyldimethylsilyl chloride in methanol;water at 20; for 0.5 h;Green chemistry;

Steps:

Synthesis of carboxylic acids pyridine-2-carboxylic acid (7), thiophene-2-carboxylic acid (8) or furan-2-carboxylic acid (9)

An appropriate alcohol [2-pyridinemethanol (3) (1.0 g, 9.20 mmol, 1 eq), 2-thiophenemethanol (4) (1.0 g, 8.78 mmol, 1 eq) or 2-furanmethanol (5) (1.0 g,10.20 mmol] was added to reaction mixture that contained Ag/ZnO/graphene nanocomposite (10 mg, 1 wt%), and TBSCl (1.38 g, 9.20 mmol, 1 eq), (1.32 g, 8.78 mmol, 1 eq), (1.53 g, 10.20 mmol, 1 eq) or (1.38 g, 9.26 mmol, 1 eq) dissolved in MeOH:H2O (1:1, 10 mL). The mixture was stirred for 30, 60 or 60 min, respectively, at room temperature and monitored by TLC using eluent system (EtOAc:Hexane, 3:7). The mixture was filtrated and then water (5 mL) was added, and the mixture was extracted with (CHCl3: MeOH, 1:1) (5 mL * 2). The collected methanol/water layer was evaporated using rotary evaporator to afford the residue that was purified by column chromatography using silica gel (Hexane:EtOAc, 7:3, 6:4 and then 1:1) to afford the corresponding carboxylic acids; pyridine-2-carboxylic acid (7); thiophene-2-carboxylic acid (8) or furan-2-carboxylicacid (9) respectively.

References:

Attia, Yasser A.;Vázquez, Carlos Vázquez;Mohamed, Yasser M. A. [Research on Chemical Intermediates,2017,vol. 43,# 1,p. 203 - 218]

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