Acrylonitrile → Tralopyril

Beteiligte Stoffe

Reaktionsschritte

A solution of N-[1-chloro-(2,2,2-trifluoroethyl)]-4-chlorobenzimidoyl chloride (5.80 g, 0.02 mol) and acrylonitrile (1.33 g, 0.025 mol) in N,N-dimethyl-formamide (15 mL) under a nitrogen atmosphere is treated with N,N-diisopropylethylamine (DIPEA, 7.8 g, 0.06 mol) over 30 minutes, heated to and held at 45-47° C. for 18 hours, cooled to room temperature, treated with bromine (3.2 g, 0.02 mol), stirred at room temperature for 1 hour, quenched with water, and extracted with ethyl acetate. The organic extract is concentrated in vacuo to obtain a residue. Flash column chromatography of the residue on silica gel, packed with 15% ethyl acetate in heptane and eluted with 20% ethyl acetate in heptane, gives the title product as white solid (1.6 g, 22.9% yield) which is identified by 1H and 19F NMR spectral analyses.

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