7-nitro-3,4-dihydro-2H-1,4-benzoxazin-3-one → 7-Nitro-3,4-dihydro-2H-1,4-benzoxazine

Participants

Reaction Steps

This compound was prepared by General Method 2 from 7-nitro-2H-1,4-benzoxazin-3(4H)-one (2.0 g, 10 mmol) and borane dimethylsulfide (2.0 M in THF, 24 mL, 48 mmol) and purified on silica gel (20:1 CH2Cl2;MeOH) to afford 1.84 g (98%) of 3,4-dihydro-7-nitro-2H-1,4-benzoxazine, an orange solid. Data for 3,4-dihydro-7-nitro-2H-1,4-benzoxazine: Rf 0.76 (11.5:1 CH2Cl2:MeOH); 1H NMR (400 MHz, CDCl3) δ 7.74 (dd, 1H, J=8.7, 2.5), 7.69 (d, 1H, J=2.5), 6.52 (d, 1H, J=8.7), 4.56 (br s, 1H), 4.26 (t, 2H, J=4.4), 3.54 (td, 2H, J=4.4, 2.5)

Provenance & Evidence