Efficient synthesis of benzofurans via cross-coupling of catechols with hydroxycoumarins using O2 as an oxidant catalyzed by AlPO4-supported Rh nanoparticle
Efficient synthesis of benzofurans via cross-coupling of catechols with hydroxycoumarins using O2 as an oxidant catalyzed by AlPO4-supported Rh nanoparticle
复制标题
AlPO4 负载 Rh 纳米颗粒催化 O2 作为氧化剂，通过儿茶酚与羟基香豆素交叉偶联高效合成苯并呋喃
DOI：
10.1002/slct.201903117
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发表时间：
2019
期刊：
影响因子：
2.1
通讯作者：
K. Jitsukawa
中科院分区：
文献类型：
--
作者：
Z. Maeno;M. Yamamoto;T. Mitsudome;T. Mizugaki;K. Jitsukawa
报道了以o2为理想氧化剂，在水中通过儿茶酚和羟基香豆素的交叉偶联高效合成苯并呋喃衍生物。上述反应允许直接使用底物而无需预官能化，以级联方式形成C−C和C−O键，并提供H2O作为唯一的副产物。这种简单而干净的反应是通过开发一种负载AlPO4的Rh纳米颗粒催化剂来实现的。该催化剂适用于多种苯并呋喃的合成。我们还成功地利用这种催化方法合成了一种天然存在的具有生物活性的原料药——flemichapparin C。Rh纳米粒子和AlPO4的结合功能在该反应中发挥了关键作用，其中Rh纳米粒子原位生成的苯醌可能是AlPO4上羟基香豆素亲核加成的中间体。
An efficient synthesis of benzofuran derivatives via the cross‐coupling of catechols and hydroxycoumarins in H2O using O2as an ideal oxidant is reported. The above reaction allows the direct use of substrates without prefunctionalization, involves formation of C−C and C−O bonds in cascade manner, and affords H2O as the sole by‐product. This simple and clean reaction is achieved by the development of an AlPO4‐supported Rh nanoparticle catalyst. The catalyst was applicable to the synthesis of a wide range of benzofurans. We also successfully utilized this catalytic method for total synthesis of flemichapparin C, one of the naturally occurring coumestans exhibiting bioactivity. The combined functions of Rh nanoparticles and AlPO4play a key role in this reaction where in situ generatedo‐benzoquinone by Rh nanoparticles is possibly an intermediate for nucleophilic addition to hydroxycoumarins on AlPO4.