Graduate School of Pharmaceutical Sciences, Osaka University.
Gifu University.
Chem Pharm Bull (Tokyo). 2023;71(10):782-786. doi: 10.1248/cpb.c23-00493.
Catechols possessing electron-withdrawing groups at the C3 position effectively underwent oxidative functionalization at the C4 position in the presence of phenyliodine(III) diacetate (PIDA) and heteroarene nucleophiles (e.g., indole, indazole, and benzotriazole) to produce the corresponding biaryl products. The PIDA-mediated oxidation of catechol derivatives afforded the ortho-benzoquinone intermediate, which subsequently underwent regioselective nucleophilic addition to the α,β-unsaturated carbonyl moiety of ortho-benzoquinone using indole, indazole, and benzotriazole to give 4-substituted catechol derivatives in a one-pot manner. Notably, the nucleophilic substitution positions of indazole and benzotriazole were perfectly controlled. Additionally, the reaction using N-methylaniline as the nucleophile afforded a tertiary amine product.
具有 C3 位吸电子基团的儿茶酚在苯碘酰三氟乙酸酯（PIDA）和杂芳环亲核试剂（如吲哚、吲唑和苯并三唑）存在下，可有效地在 C4 位发生氧化官能化反应，生成相应的联苯产物。儿茶酚衍生物的 PIDA 介导氧化生成邻苯醌中间体，随后邻苯醌的α,β-不饱和羰基部分与吲哚、吲唑和苯并三唑进行区域选择性亲核加成，以一锅法的方式得到 4-取代的儿茶酚衍生物。值得注意的是，吲唑和苯并三唑的亲核取代位置得到了很好的控制。此外，当使用 N-甲基苯胺作为亲核试剂时，可得到叔胺产物。
