4-Methylmorpholine → HCID 69019295, compound

Participants

Reaction Conditions

Reaction Steps

To a cooled (0° C., ice bath) solution of (2S)-2,3-dimethyl-3-phenylbutanoic acid (0.11 g, 0.57 mmol, from Reference Example 25), hydroxybenzotriazole (93 mg, 0.69 mmol) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimine hydrochloride (0.15 g, 0.80 mmol) in anhydrous dimethylformamide (2 ml) is added N-methylmorpholine (95 uL, 0.86 mmol) via syringe under an inert atmosphere. After stirring for 15 minutes at 0° C., the cooling bath is removed, and the resulting mixture is stirred for 1 hour. The solution is cooled at 0° C. (ice water bath), and to this mixture is added a solution of ethyl (2E,4S)-2,5-dimethyl-4-[methyl(3-methyl-L-valyl)amino]hex-2-enoate hydrochloride (0.56 mmol) in anhydrous dimethylformamide (2 ml). The cooling bath is removed, and the resulting mixture is stirred for 22 hours at room temperature under an inert atmosphere. The mixture is diluted with water, and the aqueous layer is extracted with ethyl acetate (3 times). The combined extracts are washed with saturated aqueous sodium chloride, dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The residue is chromatographed (silica gel, flash column), to provide a white foam (0.20 g, 71%). MS (ES+): (M+H)=487.0

Provenance & Evidence