1-Ethyl-3-(3'-dimethylaminopropyl)carbodiimide → (S)-(9H-fluoren-9-yl)methyl 1-(benzyl(2,2-diethoxyethyl)amino)-1-oxopropan-2-ylcarbamate

Participants

Reaction Steps

To a solution of (S)-2-(((9H-fluoren-9-yl)methoxy)carbonylamino)propanoic acid 1.98 g (6.0 mmol), a solution of 1-hydroxybenzotriazol 1.01 g (7.5 mmol) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide 1.44 g (7.5 mmol) in dichloromethane 20 ml, and a solution of N-benzyl-2,2-diethoxyethanamine (Compound IV-1) 1.12 g (5.0 mmol) and 4-dimethylaminopyridine 61 mg (0.5 mmol) in dichloromethane 5 ml were added and the mixture was stirred at room temperature overnight. The reaction mixture was diluted with ethyl acetate 20 ml and washed with saturated aqueous sodium bicarbonate 20 ml, water 20 ml and brine 20 ml. The organic phase was dried over magnesium sulfate and filtered. The filtrate was concentrated in vacuo and the residue was purified on silica gel column chromatography (n-hexane:ethyl acetate=90:10 to 70:30) to obtain the title compound 1.1 g (yield 42%).

Provenance & Evidence