Diisopropylethylamine → Methyl 3-(N'-hydroxycarbamimidoyl)-4-methylbenzoate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of methyl 3-cyano-4-methylbenzoate (compound 1.7, 8 g, 43.38 mmol, 1.00 equiv, 95%), NH2OH.HCl (3.785 g, 54.86 mmol, 1.20 equiv), and N,N-Diisopropylethylamine (DIEA, 17.7 g, 136.95 mmol, 3.00 equiv) in tetrahydrofuran (100 mL) was stirred overnight at 70° C. After cooling to room temperature, the mixture was concentrated under reduced pressure. The residue was taken up in water and the pH was adjusted to 2-3 with hydrogen chloride (aqueous, 1 M). After washing the mixture with 3×40 mL of ethyl acetate, the pH of the aqueous layer was adjusted to 8-9 with NaOH (aqueous, 2 M) followed by extraction with 3×30 mL of ethyl acetate. The combined organic layers were dried over (Na2SO4) and concentrated under reduced pressure to yield 2.76 g (29%) of the title compound as a white solid.

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