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ChemicalBook CAS DataBase List methyl 3-bromopyrazine-2-carboxylate
51171-02-9

methyl 3-bromopyrazine-2-carboxylate synthesis

2synthesis methods
-

Yield: 63%

Reaction Conditions:

with hydrogen bromide;bromine;sodium nitrite in water at 0; for 0.25 h;

Steps:

H.2 Step 2. Preparation of 3-bromopyrazine-2-carboxylic acid methyl ester
Bromine (3.91 g, 24.46 mmol) was added dropwise to a stirred mixture of 3- aminopyrazine-2-carboxylic acid methyl ester (1.27 g, 8.29 mmol) and hydrobromic acid (4.70 mL, 41.5 mmol) at 00C. A solution of sodium nitrite (1.44 g, 20.9 mmol) in water (6 mL) was then added dropwise. The reaction mixture was stirred for 15 min, brought to pH 8 with NaHCO3 (saturated, aqueous), and extracted with ethyl acetate (80 mL) and chloroform (50 mL). The combined organics were dried over MgSO4 and concentrated in vacuoto give 1.13 g (63%) of an orange oil which solidified on standing.

References:

BAYER PHARMACEUTICALS CORPORATION WO2006/91506, 2006, A2 Location in patent:Page/Page column 47

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