反应详情

A solution of tert-butyl 3-ethoxy-5,6-dihydropyrazine-1(2H)-carboxylate (0.762 g, 3.34 mmol) and tert-butyl 1-(4-chlorophenyl)-2-hydrazinyl-2-oxoethylcarbamate (1.00 g, 3.34 mmol) in toluene (6.67 mL, 3.34 mmol) was heated to reflux and stirred at this temperature for 1 hour. The reaction mixture was cooled to room temperature, diluted with ethyl acetate, and washed with water. The organic layer was dried and concentrated to give a residue that was purified by reverse phase chromatography (Biotage SP4, 40+M, C18, 10% to 100% ACN/H2O) to afford tert-butyl 3-((tert-butoxycarbonylamino)(4-chlorophenyl)methyl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazine-7(8H)-carboxylate (0.92 g, 60%). LCMS (APCI+) M+H+: 463 (25%), 464 (90%), 466 (25%), 467 (5%); rt=3.56 minutes. 1H NMR (400 MHz, CDCl3) δ □7.33 (d, J=8.6 Hz, 1H), 7.29 (d, J=8.6 Hz, 1H), 6.12 (d, J=7.8 Hz, 1H), 5.87 (d, J=7.8 Hz, 1H), 4.84 (d, J=17.6 Hz, 1H), 4.75 (d, J=17.6 Hz, 1H), 3.93 (m, 1H), 3.80 (m, 1H), 3.73 (m, 1H), 3.49 (m, 1H), 1.47 (s, 9H), 1.41 (s, 9H).

1. temperatureto reflux
2. washwashed with water
3. customThe organic layer was dried
4. concentrationconcentrated
5. customto give a residue that
6. customwas purified by reverse phase chromatography (Biotage SP4, 40+M, C18, 10% to 100% ACN/H2O)