Hydrochloric Acid → methyl 2-[(2S)-2-{[(tert-butoxy)carbonyl]amino}-4-methylpentanamido]acetate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To the solution of 5.02 g of hydrochloride of the methyl ester of glycine in a mixture of 20 ml of dichloromethane and 30 ml of dimethylformamide, cooled to 0° C., there are added 5 ml of N-ethylmorpholine then the solution of 9.5 g of dry Boc-Leucine in 50 ml of dichloromethane. 9.04 g of dicyclohexylcarbodiimide, 6 g of 1-hydroxy benzotriazol and 1.5 ml of N-ethylmorpholine are then added. After 45 minutes at 0° C., the mixture is stirred for 5 hours at ambient temperature. The insoluble is filtered and washed with ethyl acetate. The filtrate is diluted with 700 ml of ethyl acetate and the organic solution is washed 3 times with an aqueous solution of sulfate and potassium bisulfate, then 3 times with a saturated sodium bicarbonate solution and finally 3 times with a saturated sodium chloride solution. The organic solution dried over sodium sulfate is concentrated in vacuo to 200 ml. 150 ml of hexane are added and the mixture is left to crystallize, drained and washed with hexane.

Herkunft & Nachweise