反应详情

A solution of 4.0 g (16 mmoles) of 6-nitro-5-methyl-2-ethoxy-3,1-benzoxazin-4-one in 65 mL ethyl acetate was transferred to a Parr bottle. 1.0 g (0.94 mmoles) 10% Pd/C catalyst (obtained from Matheson, Coleman & Bell) was added. The sample was hydrogenated on a Parr shaker at ambient room temperature and 1 atm pressure for 5 hours. The catalyst was removed by filtration through a pad of Celite. The filtrate was concentrated in vacuo to produce a bright yellow solid. There was obtained 2.5 g (71% yield) of 6-amino-5-methyl-2-ethoxy-3,1-benzoxazin-4-one. NMR (DMSO-d6): 1.33(t,3H,J=6.9 Hz), 2.46(s,3H), 4.36(q,2H,J=6.9 Hz), 5.24(bs,2H), 7.05(d,1H,J=8.4 Hz), 7.14(d,1H,J=8.4 Hz). IR(nujol): 1743 cm-1 (lactone carbonyl). MS(m/z): 220(M+).

1. customwas hydrogenated on a Parr shaker at ambient room temperature
2. customThe catalyst was removed by filtration through a pad of Celite
3. concentrationThe filtrate was concentrated in vacuo
4. customto produce a bright yellow solid