ChemicalBook CAS DataBase List 5-Bromo-6-chloronicotinic acid

5-Bromo-6-chloronicotinic acid synthesis

4synthesis methods

Product Name:5-Bromo-6-chloronicotinic acid
CAS Number:29241-62-1
Molecular formula:C6H3BrClNO2
Molecular Weight:236.45

41668-13-7

29241-62-1

Synthesis of 5-bromo-6-chloronicotinic acid: 5-bromo-6-hydroxynicotinic acid (10 g, 45 mmol), tetramethylammonium chloride (5.4 g, 49 mmol), and phosphorus triclosan (20 mL) were sequentially added to a reaction flask, and the mixture was heated to reflux and held for 3 hours. Upon completion of the reaction, the reaction mixture was slowly poured into ice water and stirred continuously for 2 hours. The precipitated solid was collected by filtration, dissolved in ethyl acetate (300 mL) and dried by adding anhydrous sodium sulfate. The desiccant was removed by filtration and the filtrate was concentrated under reduced pressure to give 10.5 g (97% yield) of the target product 5-bromo-6-chloronicotinic acid as a pink solid. The product was characterized by 1H NMR (400 MHz, DMSO-d6): δ 8.53 (d, J = 2.02 Hz, 1H), 8.85 (d, J = 2.02 Hz, 1H), 13.57 (s, 1H).

41668-13-7 Synthesis

41668-13-7
175 suppliers
$13.00/1g

29241-62-1
245 suppliers
$5.00/250mg

Yield:29241-62-1 97%

Reaction Conditions:

Stage #1:5-bromo-6-hydroxy-3-pyridinecarboxylic acid with tetramethlyammonium chloride;trichlorophosphate for 3 h;Heating / reflux;
Stage #2: with water at 0; for 2 h;

Steps:

8.B
8B. 5-Bromo-6-chloro-nicotinic acid: To 8A (10 g, 45 mmol) was added tetra-methylammonium chloride (5.4 g, 49 mmol) and phosphorous oxychloride (20 mL) and the reaction was heated at reflux for 3 h. The reaction was poured onto ice and stirred 2 h. The solid was filtered off, dissolved in EtOAc (300 mL) and dried (Na₂SO4). After filtration and concentration, 10.5g (97%) of 8B as a pink solid was collected. ¹HNMR (400 MHz, DMSO-d₆) δ: 8.53 (d, J = 2.02 Hz, 1H) 8.85 (d, J = 2.02 Hz, 1 H) 13.57 (s, 1 H).

References:

BRISTOL-MYERS SQUIBB COMPANY WO2007/70818, 2007, A1 Location in patent:Page/Page column 103

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