Benzylamine → 2-Bromo-4-methyl-thiazole-5-carboxylic acid benzylamide

To a solution of 2-bromo-4-methylthiazole-5-carboxylic acid (9.00 g, 40.0 mmol) in anhydrous tetrahydrofuran (140 mL) was added N,N-diisopropylethylamine (20.76 mL, 121.0 mmol) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (10.87 g, 56.0 mmol). The reaction mixture was stirred at ambient temperature for 0.5 hours and 1-hydroxybenzotriazole (7.60 g, 56.0 mmol) and benzyl amine (6.00 g, 56.0 mmol) were added. The resulting mixture was stirred at ambient temperature for 18 hours, then concentrated to half volume in vacuo, diluted with dichloromethane (400 mL), and washed with water (400 mL) and brine (150 mL). The organic layer was dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The residue was purified by column chromatography eluted with ethyl acetate/hexane (1/1) to afford the title compound as a colorless solid in 70% yield (8.89 g): mp 92-94° C. (ethyl acetate/hexanes); 1H NMR (300 MHz, CDCl3) δ 7.41-7.23 (m, 5H), 5.94 (br s, 1H), 4.57 (d, J=5.6 Hz, 2H), 2.64 (s, 3H); MS (ES+) m/z 311.0 (M+1), 313.1 (M+3).

1. stirringThe resulting mixture was stirred at ambient temperature for 18 hours
2. concentrationconcentrated to half volume in vacuo
3. additiondiluted with dichloromethane (400 mL)
4. washwashed with water (400 mL) and brine (150 mL)
5. dry with materialThe organic layer was dried over anhydrous sodium sulfate
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customThe residue was purified by column chromatography
9. washeluted with ethyl acetate/hexane (1/1)

ORD record

ord-986e7399523f4f17abb7e6f4151ce5c7

Source dataset

uspto-grants-2012_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08293768B2