Acetonitrile → (S)-2-[(5-chloro-2-formyl-2H-chromen-3-ylmethyl)-methyl-amino]-4-methyl-pentanoic acid methyl ester

Participants

Reaction Steps

A solution of 5-chloro-3-[((S)-1-methoxycarbonyl-3-methyl-butylamino)-methyl]-2H-chromene-2-carboxylic acid methyl ester (1.4 g, 3.53 mmol) and N,N′-diisopropylethyl amine (2.44 mL, 14.14 mmol) in acetonitrile (3 mL) was heated in a sealed tube at 140° C. for 48 hours. The reaction mixture, after aqueous work-up, was extracted with ethyl acetate (3×). The combined ethyl acetate layer was washed with brine, and dried over anhydrous sodium sulfate. The organic layer was concentrated in vacuo and the residue was purified using flash chromatography over neutral alumina (eluant-hexanes-ethyl acetate 1:3, Rf=0.3) to afford (S)-2-[(5-chloro-2-formyl-2H-chromen-3-ylmethyl)-methyl-amino]-4-methyl-pentanoic acid methyl ester (1.02 g, 71.4%) as a solid.

Provenance & Evidence