反应详情

The procedure for the synthesis of 19 was followed (1 eq. bromine was used) to prepare 20 from 19 as white crystals in a 50% yield. 1H NMR (400 MHz, CDCl3, 298 K): δ(ppm) 8.04-8.03 (d, J=2.00 Hz, 2H), 7.60-7.59 (d, J=2.00 Hz, 1H), 7.58-7.57 (d, J=2.00 Hz, 1H), 7.47 (s, 1H), 7.44 (s, 1H).