Dutta Shubham, Yang Shengwen, Vanjari Rajeshwer, Mallick Rajendra K, Gandon Vincent, Sahoo Akhila K
School of Chemistry, University of Hyderabad, Hyderabad, India.
Institut de Chimie Moléculaire et des Matériaux d'Orsay, CNRS UMR 8182, Université Paris-Saclay, Bâtiment 420, 91405, Orsay cedex, France.
Angew Chem Int Ed Engl. 2020 Jun 26;59(27):10785-10790. doi: 10.1002/anie.201915522. Epub 2020 Mar 2.
A three-component Pd-catalyzed coupling of ynamides, aryl diazonium salts, and aryl boronic acids for the synthesis of novel triaryl-substituted enamides is described. This transformation represents the first example of an umpolung regioselective unsymmetrical syn-1,2-diarylation/aryl-olefination of ynamides. The aryl moieties of the diazonium salt (electrophile) and boronic acid (nucleophile) are explicitly incorporated in the electrophilic α- and nucleophilic β-position, respectively, of the ynamide, resulting in a single isomer of the N-bearing tetrasubstituted olefin. The scope is broad (68 examples), showing excellent functional-group tolerance. DFT calculations substantiate the rationale of the mechanistic cycle and the regioselectivity. The chemoselectivity and synthetic potential of the enamide products were also studied.
描述了一种用于合成新型三芳基取代烯酰胺的钯催化的炔酰胺、芳基重氮盐和芳基硼酸的三组分偶联反应。这种转化代表了炔酰胺的极性反转区域选择性不对称顺式1,2-二芳基化/芳基烯化反应的首个实例。重氮盐（亲电试剂）和硼酸（亲核试剂）的芳基部分分别明确地引入到炔酰胺的亲电α位和亲核β位，得到含氮四取代烯烃的单一异构体。该反应适用范围广泛（68个实例），显示出优异的官能团耐受性。密度泛函理论计算证实了机理循环和区域选择性的原理。还研究了烯酰胺产物的化学选择性和合成潜力。
