Hexafluorophosphate → 2-Azido-4-(4-trifluoromethyl-phenyl)-thiazole-5-carboxylic acid amide

Participants

Reaction Steps

To a solution of 1.76 g (5.60 mmole) of 2-azido-4-(4-trifluoromethyl-phenyl)-thiazole-5-carboxylic acid and 30 mL of dimethylformamide was added 2.75 g (7.01 mmole) of 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium, 3-oxide, hexafluorophosphate(1-) (1:1) and 3.0 mL (17.2 mmole) of ethyldiisopropylamine. The mixture was stirred for 18 minutes, then 0.4541 g (8.49 mmole) of ammonium chloride was added. The mixture was concentrated under reduced pressure and diluted with 350 mL of ethyl acetate and 75 mL of water. The ethyl acetate layer was washed with 50 mL of water, 50 mL of saturated aqueous sodium bicarbonate, 50 mL of brine, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The residue was purified by silica gel chromatography, eluting with ethyl acetate-hexanes (gradient 10:90-100:0) to give 1.384 g of 2-azido-4-(4-trifluoromethyl-phenyl)-thiazole-5-carboxylic acid amide as a light yellow solid.

Provenance & Evidence