Expeditious synthesis of pyrano[2,3,4-de]quinolines via Rh(<scp>iii</scp>)-catalyzed cascade C–H activation/annulation/lactonization of quinolin-4-ol with alkynes
作者:Gang Liao、Hong Song、Xue-Song Yin、Bing-Feng Shi
DOI:10.1039/c7cc04113f
日期:——
One-step synthesis of tetracyclic pyrano[2,3,4-de]quinolones via Rh(iii)-catalyzed cascade C–H activation/annulation/lactonization is described.
Manganese‐Catalysed C−H Activation: A Regioselective C−H Alkenylation of Indoles and other (hetero)aromatics with 4‐Hydroxy‐2‐Alkynoates Leading to Concomitant Lactonization
A manganese‐catalyzed C−H bond alkenylation of indoles at C2‐position with 4‐hydroxy‐2‐alkynoatesleading to concomitantlactonization under removable directing group strategy has been disclosed. This lactonization strategy exhibits regioselectivity, a broad substrate scope, and a good functional group tolerance furnishing the products in low to high yields. The regioselectivity is guided by the electronic
Rhodium(III)-Catalyzed C–H Activation: A Cascade Approach for the Regioselective Synthesis of Fused Heterocyclic Lactone Scaffolds
作者:Anil Kumar、Kandikere Ramaiah Prabhu
DOI:10.1021/acs.joc.9b03266
日期:2020.3.6
A Rh(III)-catalyzed cascade C-H activation; regioselective [4 + 2] oxidative annulation; and lactonization of aromatic acids, anhydrides, and acrylic acid derivatives with 4-hydroxy-2-alkynoates have been disclosed. This strategy leads to fused heterocyclic lactone scaffolds in a single step with moderate functional group tolerance and excellent site selectivity. Besides, in one step, an antipode of
Rhodium‐Catalyzed Regioselective C—O and C—C Bonds Formation of 3‐Oxopent‐4‐enenitriles with Alkynes for the Synthesis of Polysubstituted 2H‐Pyrans
作者:Kelu Yan、Xiao Liu、Jiangwei Wen、Qiuyun Li、Junjie Wang、Yang Zheng、Xiu Wang
DOI:10.1002/cjoc.202400239
日期:2024.9
The rhodium-catalyzedC—Hbondactivation and cyclization of 3-oxopent-4-enenitriles with alkynes proceed efficiently. Various 2H-pyrans with multiple substituents are achieved in good yields through regioselective formation of C—O and C—C bonds. Transformations involving hydroxy-alkynoates resulted in products with a furo[3,4-b]pyran skeleton via further intramolecular ester exchange processes. Different
铑催化的 C—H 键活化以及 3-氧代戊基-4-烯腈与炔烃的环化反应高效进行。通过区域选择性形成CO和CC键,可以以良好的产率获得具有多个取代基的各种2H-吡喃。涉及羟基炔酸酯的转化通过进一步的分子内酯交换过程产生具有呋喃[3,4- b ]吡喃骨架的产物。与传统的“1-氧三烯途径”不同,该方法合成有用的2H-吡喃的方法在底物易得、产物稳定易衍生化、操作过程温和便捷、步骤和原子经济性等方面具有一定的亮点。