在本文中, 催化剂不同地取代的6的-free合成ħ -苯并[ c ^ ]色烯和6 ħ -苯并[ c ^ ]苯并吡喃-8-醇通过的级联反应2-(2-(烯丙氧基)苯基)呋喃 和 2-(2-(丙-2-炔氧基)苯基)呋喃,具有分子内Diels–Alder反应 呋喃 与未激活 烯烃/炔烃在MWI下的水性介质中进行了开发。另外,环保氧化作用还揭示了在没有任何活化剂/催化剂的情况下,使用H 2 O 2作为氧化剂,将6 H-苯并[ c ]色烯转化为相应的苯并[ c ]色烯-6 。
An efficient and robust methodology based on electrochemical techniques for the direct synthesis of aromatic lactones through dehydrogenative C−O cyclization is described. This new and useful electrochemical reaction can tolerate a variety of functional groups, and is scalable to 100 g under mild conditions. Remarkably, heterocycle‐containing substrates can be employed, thus expanding the scope of
Cerium photocatalyzed dehydrogenative lactonization of 2-arylbenzoic acids
作者:Ketan Wadekar、Suraj Aswale、Veera Reddy Yatham
DOI:10.1039/c9ob02676b
日期:——
The first cerium photocatalyzed dehydrogenative lactonization of 2-arylbenzoic acids has been developed. This operationally simple protocol allows rapid access to synthetically useful coumarins on gram scale by employing CeCl3 as a photocatalyst and O2 as a terminal oxidant. Overall, this delivers an economical and environmentally amiable entry to diversely substituted coumarins, important structural
A practical, electrochemical method is developed for the direct dehydrogenative lactonization of C(sp2/sp3)–H bonds under external oxidant- and metal-free conditions, delivering diverse lactones, including coumarin derivatives with excellent regioselectivity. The scalable nature of this newly developed electrochemical process was demonstrated on a 40 g scale following an operationally simple protocol
Organocatalytic Electrochemical C–H Lactonization of Aromatic Carboxylic Acids
作者:Sanzhong Luo、Longji Li、Qi Yang、Zongbin Jia
DOI:10.1055/s-0036-1591558
日期:2018.8
Radical Methods and their Strategic Applications in Synthesis Abstract An electrochemical strategy has been developed for radical arene carbon–oxygen bond formation. This reaction utilizes DDQ as a redox mediator, with inexpensive glassy carbon electrodes to facilitate an intramolecular lactonization of biphenyl-2-carboxylic acid derivatives via aromatic carboxyl radical substitution to give 6H-be
§这些作者同等贡献。 作为特别主题“现代自由基方法及其在合成中的战略应用”的一部分发布 抽象的 已经开发出一种用于自由基芳烃碳-氧键形成的电化学策略。该反应利用DDQ作为氧化还原介体,并具有廉价的玻璃碳电极,以通过芳族羧基自由基取代促进联苯-2-羧酸衍生物的分子内内酯化,得到6 H-苯并[ c ] chromen-6-one。 已经开发出一种用于自由基芳烃碳-氧键形成的电化学策略。该反应利用DDQ作为氧化还原介体,并具有廉价的玻璃碳电极,以通过芳族羧基自由基取代促进联苯-2-羧酸衍生物的分子内内酯化,得到6 H-苯并[ c ] chromen-6-one。