Solvent-free iodine-promoted synthesis of 3,2′-pyrrolinyl spirooxindoles from alkylidene oxindoles and enamino esters under ball-milling conditions
作者:Hui Xu、Hong-Wei Liu、Hao-Sheng Lin、Guan-Wu Wang
DOI:10.1039/c7cc08306h
日期:——
A solvent-free mechanochemical reaction of alkylidene oxindoles with enamino esters via an iodine-promoted tandem Michael/cyclization sequence has been developed to provide a variety of spirocyclic oxindoles in moderate to good yields with excellent diastereoselectivities.
Regioselective Iodine-Catalyzed Construction of Polysubstituted Pyrroles from Allenes and Enamines
作者:Yu Wang、Chen-Min Jiang、Hong-Liang Li、Fu-Sheng He、Xiaoyan Luo、Wei-Ping Deng
DOI:10.1021/acs.joc.6b01737
日期:2016.9.16
A novel I2-catalyzed tandem Michael addition/oxidative annulation of allenes and enamines for the construction of polysubstituted pyrroles has been developed. This protocol represents an efficient and highlyregioselective way to accessfunctionalizedpyrroles in moderate to excellent yields under mild conditions.
A new synthetic approach to polyfunctional hexahydropyrrolo[3,4-b]pyrroles was developed based on cyclization of N-arylbromomaleimides with aminocrotonic acid esters. A highly chemo- and stereoselective reaction is a Hantzsch-type domino process, involving the steps of initial nucleophilic C-addition or substitution and subsequent intramolecular nucleophilic addition without recyclyzation of imide
A novel and efficient I2/FeCl3-catalyzed dominoreaction of aurones with enamino esters via Michael addition, iodination, intramolecular nucleophilicsubstitution, and spiro ring opening processes has been developed, affording a vast variety of polysubstituted pyrroles in moderate to excellent yields. This protocol features mild reaction conditions, broad substrate scope, high atom economy and efficiency
已开发出一种新颖且高效的 I 2 /FeCl 3催化的金酮与烯胺酯的多米诺反应,通过迈克尔加成、碘化、分子内亲核取代和螺环开环过程,以中等至优异的收率提供多种多取代吡咯。该方案具有反应条件温和、底物范围广、原子经济性和效率高以及大规模合成的可行性等特点。提出了一种可能的吡咯合成机理。
Mechanosynthesis of Pyrrole-2-carboxylic Acids via Copper-Catalyzed Spiroannulation/Ring-Opening Aromatization of 4-Arylidene Isoxazol-5-ones with Enamino Esters
and practical tandemreaction of 4-arylidene isoxazol-5-ones with enamino esters catalyzed by an inexpensive copper salt has been established in a ball mill. This innovative approach yields a diverse array of structurally novel pyrrole-2-carboxylic acids, showing excellent tolerance toward different functional groups. By integrating spiroannulation and ring-opening aromatization processes, this protocol