Hydrogen Bromide → Ethyl 2-bromo-4-methyl-1,3-thiazole-5-carboxylate

HRID 1057766Notes

Reaction equation

N[C:2]1[S:3][C:4]([C:8]([O:10][CH2:11][CH3:12])=[O:9])=[C:5]([CH3:7])[N:6]=1.P(=O)(O)(O)O.[N+]([O-])(O)=O.N([O-])=O.[Na+].[BrH:26]>O>[Br:26][C:2]1[S:3][C:4]([C:8]([O:10][CH2:11][CH3:12])=[O:9])=[C:5]([CH3:7])[N:6]=1

Participants

Conditions

Temperature: 0 °C

Procedure

Ethyl 2-amino-4-methylthiazole-5-carboxylate (1.20 g, 6.44 mmoles) was added to a solution of 85% phosphoric acid (18 mL) and 70% nitric acid (9 mL) at 0° C. Aqueous sodium nitrite(1.38 g (20 mmol) in water (9 mL) was immediately added dropwise over 20 minutes. After stirring at 0° C. for 15 minutes, cuprous bromide (930 mg, 6.44 mmoles) in hydrobromic acid (9 mL) was added. After stirring for 10 minutes, water (30 mL) was added. The mixture was filtered and the crude solid purified via silica gel chromatography (10% ethyl acetate/hexane) to afford 1.15 g (4.6 mmoles) of the product as a yellow solid (71%). H1 NMR (CDCl3) δ 4.35 (2H, q, J=7.1 Hz), 2.73 (3H, s), 1.38 (3H, t, J=7.1 Hz).

Workup

stirringAfter stirring for 10 minutes
filtrationThe mixture was filtered
customthe crude solid purified via silica gel chromatography (10% ethyl acetate/hexane)

Sources & evidence

ORD record: ord-de540f927675486d9e6276a6d79f4534
Source dataset: uspto-grants-2003_02
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US06515005B2

Reaction notes

Loading…