反应详情

Intermediate I-18a was prepared from 5-amino-6,7-difluoro-1-(2-fluoro-4-iodo-phenyl)-4-hydroxy-1,3-dihydro-benzoimidazol-2-one (I-13a: 550 mg, 1.3 mmol) in 1,1,1-triethoxy-ethane (5 mL) and p-toluene sulfonic acid (20 mg, 0.13 mmol) using procedures analogous to those described above for Intermediate I-16a to afford 310 mg of the product (53.6% yield). H1NMR (DMSO-d6, 300 MHz): δ 12.39 (s, 1H), 7.96 (dd, 1H), 7.78 (d, 1H), 7.48 (t, 1H), 2.67 (s, 3H). LCMS: 92.6%, m/z=445.9 (M+1).