Yunyun Ning1, Shuaishuai Wang1, Muzi Li1, Jie Han1, Chengjian Zhu1,2, Jin Xie3,4. 1. State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China. 2. College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou, China. 3. State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China. xie@nju.edu.cn. 4. Advanced Catalytic Engineering Research Center of the Ministry of Education, Hunan University, Changsha, China. xie@nju.edu.cn.
Abstract
Development of catalytic amide bond-forming methods is important because they could potentially address the existing limitations of classical methods using superstoichiometric activating reagents. In this paper, we disclose an Umpolung amidation reaction of carboxylic acids with nitroarenes and nitroalkanes enabled by the triplet synergistic catalysis of FeI2, P(V)/P(III) and photoredox catalysis, which avoids the production of byproducts from stoichiometric coupling reagents. A wide range of carboxylic acids, including aliphatic, aromatic and alkenyl acids participate smoothly in such reactions, generating structurally diverse amides in good yields (86 examples, up to 97% yield). This Umpolung amidation strategy opens a method to address challenging regioselectivity issues between nucleophilic functional groups, and complements the functional group compatibility of the classical amidation protocols. The synthetic robustness of the reaction is demonstrated by late-stage modification of complex molecules and gram-scale applications.
Development of catalyticpan class="Chemical">amide bond-forming methods is imclass="Chemical">portant because they could class="Chemical">potentially address the existing limitations of classical methods using suclass="Chemical">perstoichiometric activating reagents. In this class="Chemical">paclass="Chemical">per, we disclose an Umclass="Chemical">polung amidation reaction of class="Chemical">pan class="Chemical">carboxylic acids with nitroarenes and nitroalkanes enabled by the triplet synergistic catalysis of FeI2, P(V)/P(III) and photoredox catalysis, which avoids the production of byproducts from stoichiometric coupling reagents. A wide range of carboxylic acids, including aliphatic, aromatic and alkenyl acids participate smoothly in such reactions, generating structurally diverse amides in good yields (86 examples, up to 97% yield). This Umpolung amidation strategy opens a method to address challenging regioselectivity issues between nucleophilic functional groups, and complements the functional group compatibility of the classical amidation protocols. The synthetic robustness of the reaction is demonstrated by late-stage modification of complex molecules and gram-scale applications.
Authors: D Christopher Braddock; Paul D Lickiss; Ben C Rowley; David Pugh; Teresa Purnomo; Gajan Santhakumar; Steven J Fussell Journal: Org Lett Date: 2018-02-02 Impact factor: 6.005