反应详情

A solution of 3,5-dihydroxy-4-((E)-3-phenyl-allyl)-benzoic acid methyl ester (220h) (12 g, 0.032 mol) in HCl (g)/MeOH (4 N, 150 mL) was stirred at room temperature for 2 days. The reaction solution was concentrated to give a brown solid. The crude solid was re-crystallized from EtOAc to give the product (7 g) as a yellow solid. The mother liquid was concentrated to give a brown solid (5 g). The total yield is 98%. 1H NMR (400 MHz, CDCl3): δ 9.90 (br, 1H), 7.27˜7.46 (m, 5H), 7.00 (s, 1H), 6.87 (s, 1H), 5.07 (d, 1H), 3.78 (s, 3H), 2.65 (d, 2H), 2.16 (m, 1H), 1.92 (m, 1H).

1. concentrationThe reaction solution was concentrated
2. customto give a brown solid
3. customThe crude solid was re-crystallized from EtOAc