5-Amino-2-bromo-thiazole-4-carboxylic acid methyl ester synthesis

Yield:1373223-08-5 99%

Reaction Conditions:

with N-Bromosuccinimide in tetrahydrofuran at 20 - 30; for 1 h;

Steps:

1.3 Methyl 5-amino-2-bromo-1,3-thiazole-4-carboxylate

To a solution of methyl 5-amino-1,3-thiazole-4-carboxylate (J & W PharmLab, 10.0 g, 63.2 mmol) in THF (100 mL), N-bromosuccinimide (12.0 g, 67.4 mmol) was added portion-wise. After stirring at room temperature for 1 h, the mixture reaction was filtered to give a first crop of product as a pink solid (9.8 g). The filtrate was concentrated under reduced pressure. The resulting residue was triturated with EtOAc (15 mL) and filtered to give a second crop of product as a pink solid (5.0 g, total yield: 99%). LCMS calc. for C₅H₆BrN₂O₂S (M+H)⁺: m/z=236.9. found 237.0.

References:

US2014/200227,2014,A1 Location in patent:Page/Page column 0539; 0540