ChemicalBook CAS DataBase List 2,6-Dichloroisonicotinic acid

2,6-Dichloroisonicotinic acid synthesis

11synthesis methods

Product Name:2,6-Dichloroisonicotinic acid
CAS Number:5398-44-7
Molecular formula:C6H3Cl2NO2
Molecular Weight:192

99-11-6

5398-44-7

The general procedure for the synthesis of 2,6-dichloroisonicotinic acid from citrazinic acid was as follows: citrazinic acid (10.35 g, 66.7 mmol) and tetraethylammonium chloride (11.05 g, 66.7 mmol) were suspended in phosphorochloride (20 mL, in excess) and the reaction was heated for 18 hr at 130 °C, followed by warming up to 145 °C to continue the reaction for 2 hr. Upon completion of the reaction, the mixture was cooled to room temperature and slowly poured into crushed ice (150 g) for quenching. The reaction mixture was extracted with ethyl acetate (3 x 100 mL), the organic phases were combined and dried over anhydrous magnesium sulfate. The organic phase was concentrated under reduced pressure to afford the white solid product 2,6-dichloroisonicotinic acid 11.34 g in 89% yield. The product was characterized by 1H NMR (400 MHz, DMSO-d6): δ 7.85 (s, 2H), 13.90 (br s, OH).

99-11-6 Synthesis

99-11-6
271 suppliers
$11.00/10g

5398-44-7
329 suppliers
$6.00/1g

Yield:5398-44-7 89%

Reaction Conditions:

with tetraethylammonium chloride;trichlorophosphate at 130 - 145; for 20 h;

Steps:

16 Example 16-2,6-dichloroisonicotinic acid
Citrazinic acid (10.35 g, 66.7 mmol) and tetraethylammonium chloride (11.05 g, 66.7 mmol) were suspended in phosphoroxychloride (20 mL, excess) and heated at 130 °C for 18 h and then at 145 °C for 2 h. The reaction mixture was allowed to cool to RT and poured onto crushed ice (150 g). Extraction of ethyl acetate (3 x 100 mL), drying of the combined organic layers (MGS04) and evaporation in vacuo gave 11. 34 g (89 %) of a white solid. IH NMR (400 MHz, DMSO-d6) 8 7.85 (s, 2H) 13.90 (br s, OH).

References:

BIOVITRUM AB WO2004/63156, 2004, A1 Location in patent:Page 35

FullText