4-Fluorobenzylamine → 2-Bromo-N-(4-fluorobenzyl)-4-methylthiazole-5-carboxamide

Participants

Reaction Steps

Part A. To a solution of 2-bromo-4-methyl-thiazole-5-carboxylic acid (10 g, 45.0 mmol, 1.0 equiv) and diisopropylethylamine (15.6 mL, 90.0 mmol, 2.0 equiv) in anhydrous dichloromethane (400 mL) was added benzotriazol-1-yloxytris-(dimethylamino)phosphonium hexafluorophosphate (BOP reagent, 22 g, 49.5 mmol, 1.1 equiv) and 4-fluorobenzylamine (5.7 mL, 49.5 mmol, 1.1 equiv). The resulting mixture was stirred at ambient temperature for 12 hr. The reaction mixture was diluted with dichloromethane, washed with water then brine, dried (Na2SO4), filtered and concentrated in vacuo. The crude product was purified by column chromatography [SiO2, ethyl acetate/hexanes, 10:90 to 40:60, v/v], followed by stirring in pentane and filtering the solid to afford 2-bromo-4-methyl-thiazole-5-carboxylic acid 4-fluoro-benzylamide (8.5 g, 57% yield). MS (M+H)+=330.1, Rt=1.36 min.

Provenance & Evidence