Pd-Catalyzed Branching Cyclizations of Enediyne-Imides toward Furo[2,3-b]pyridines
摘要:
The convergent synthesis of a class of enediyneimides as well as their palladium-catalyzed branching cyclizations, which can be accomplished in two ways leading to a set of polysubstituted furo[2,3-b]pyridines upon using the N-tosyl carboxamide moiety as an N,O-bisnucleophile, are presented.
Palladium/Copper-Catalyzed Aerobic Intermolecular Cyclization of Enediyne Compounds and Alkynes: Interrupting Cycloaromatization for (4 + 2) Cross-Benzannulation
作者:Fei Ling、Zexiang Li、Chenguang Zheng、Xiang Liu、Cheng Ma
DOI:10.1021/ja506795u
日期:2014.8.6
A tandem coupling-ketooxygenation reaction of readily accessible enediyne-carboxylic compounds with inner alkynes has been developed that utilizes the PdCl2/CuBr2 catalytic system under an O-2 atmosphere and assembles a class of isoindolinones and o-acylbenzoic acids. The two oxygen atoms are regioselectively incorporated into enediyne units at the 1- and 6-positions from atmospheric molecular oxygen and H2O, respectively, during the present process. This study uncovered a formal [4C + 2C] benzannulation diketonization of enediynes and alkynes via a coupling and decoupling strategy.