Dong Yu, Zhang Hua, Yang Jian, He Shuai, Shi Zhi-Chuan, Zhang Xiao-Mei, Wang Ji-Yu
Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China.
University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
ACS Omega. 2019 Dec 3;4(25):21567-21577. doi: 10.1021/acsomega.9b03328. eCollection 2019 Dec 17.
An atom-economical and environmentally benign approach for the synthesis of indole-substituted 1,4-naphthoquinones from indoles and 1,4-naphthoquinones using readily available Lewis acidic B(CF) in water and with the recycling of water and part of the catalyst is reported. The reaction proceeded through the B(CF)-catalyzed C(sp)-H and C(sp)-H bond coupling of 1,4-naphthoquinones with the C-3 position of indole derivatives in water. This methodology provides a facile protocol for the synthesis of some new indole-substituted 1,4-naphthoquinones in satisfactory yields and with a broad substrate scope. When compared to known methods for the synthesis of indole-substituted 1,4-naphthoquinones, this protocol is practical and efficient and does not require a transition-metal catalyst or toxic organic solvents. In addition, we utilized a simple filtration process for complete recycling of the solvent and the part of the catalyst in each reaction cycle.
报道了一种原子经济且环境友好的方法，该方法用于在水中使用易于获得的路易斯酸B(CF)，从吲哚和1,4-萘醌合成吲哚取代的1,4-萘醌，并实现水和部分催化剂的循环利用。该反应通过B(CF)催化1,4-萘醌与吲哚衍生物的C-3位在水中进行C(sp)-H和C(sp)-H键偶联。该方法提供了一种简便的方案，以令人满意的产率和广泛的底物范围合成一些新的吲哚取代的1,4-萘醌。与已知的合成吲哚取代的1,4-萘醌的方法相比，该方案实用且高效，不需要过渡金属催化剂或有毒有机溶剂。此外，我们采用简单的过滤过程，在每个反应循环中实现溶剂和部分催化剂的完全循环利用。
