Dicyclohexylcarbodiimide → 2-{[(3r)-4-(4-Toluenesulfonyl)thiomorpholine-3-carbonyl]amino}-3-methyl-butyric acid benzyl ester

Beteiligte Stoffe

Reaktionsschritte

0.301 g (1 mmol) of (3R)-4-(4-toluenesulfonyl)thiomorpholine-3-carboxylic acid, 0.417 g (1.1 mmol) of L-valine benzyl ester p-toluenesulfonic acid salt, 0.227 g (1.2 mmol) of DCC and 0.122 g (1 mmol) of DMAP were dissolved in 30 mL of CH2Cl2, 0.2 ml (1.4 mmol) of TEA was added. The mixture was stirred for 24 h at room temperature. The solid was filtrated and the solvent was evaporated. The residual was dissolved in a suitable amount of ethyl acetate (20 ml) and then the mixture was filtered to remove insoluble substance. The ethyl acetate was added to 60 ml and then the liquid was washed with 10% NaHCO3 solution, saturated NaCl solution and dried over Na2SO4. After the drying agent was removed and part of ethyl acetate was evaporated, the crude product was purified by flash column chromatography (eluent: CH2Cl2:CH3Cl=1:1) to obtain the product as a glassy solid (0.20 g).

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