Dicyclohexylcarbodiimide → (2RS, 3S)-3-(tert-butoxycarbonyl)amino-4-cyclohexyl-2-hydroxy-N-isobutylbutyramide

Participants

Reaction Steps

To a solution of 400 mg of the butyric acid compound, 175 mg of isobutylamine hydrochloride, 270 mg of 1-hydroxybenzotiazole and 0.22 ml of triethylamine in 20 ml of ethyl acetate was added 300 mg of dicyclohexylcarbodiimide with stirring under ice-cooling, and then the mixture was still stirred for 16 hours. The reaction mixture was cooled, and filtered to remove insoluble materials. The filtrate was washed successively with an aqueous citric acid solution, a 5% aqueous sodium bicarbonate solution and a saturated sodium chloride aqueous solution, dried over anhydrous magnesium sulfate, and evaporated under reduced pressure to obtain 595 mg of (2RS, 3S)-3-(tert-butoxycarbonyl)amino-4-cyclohexyl-2-hydroxy-N-isobutylbutyramide.

Provenance & Evidence