Diisopropylethylamine → (Z)-3-(3-(3,5-bis(trifluoromethyl)phenyl)-1H-1,2,4-triazol-1-yl)-N'-pivaloylacrylohydrazide

関与物質

反応条件

反応手順

In a 50 mL, 3-neck round-bottom flask, (Z)-3-(3-(3,5-bis(trifluoromethyl)phenyl)-1H-1,2,4-triazol-1-yl)acrylic acid (0.2 g, 1.0 eq.) was dissolved in EtOAc (20 mL) and cooled to −60° C. where pivalohydrazide (0.08 g, 1.2 eq.) was introduced dropwise. T3P (50% in EtOAc) (0.4 mL, 4 eq.) was added dropwise followed by DIPEA (0.4 mL, 4 eq.) and the reaction mixture was stirred for 1 h at −60° C. The reaction mixture was concentrated under reduced pressure (25° C., 20 mm Hg) to afford the crude product that was purified by column chromatography (60/120 silica gel) using methanol/dichloromethane gradient (the column was packed in dichloromethane and the desired compound started eluting from 3% methanol/dichloromethane). Fractions containing the desired compounds were combined to afford (Z)-3-(3-(3,5-bis(trifluoromethyl)phenyl)-1H-1,2,4-triazol-1-yl)-N′-pivaloylacrylohydrazide (0.11 g, yield: 43%);

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