Prabagar B, Mallick Rajendra K, Prasad Rangu, 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-Sud, Université Paris-Saclay, Bâtiment 420, 91405, Orsay cedex, France.
Angew Chem Int Ed Engl. 2019 Feb 18;58(8):2365-2370. doi: 10.1002/anie.201813143. Epub 2019 Jan 21.
A regioselective sulfonyl/sulfinyl migration cycloisomerization cascade of alkyne-tethered ynamides is developed in the presence of XPhosgold catalyst. This reaction is the first example of a general [1,3]-sulfonyl migration from the nitrogen center to the β-carbon atom of ynamides, followed by umpolung 5-endo-dig cyclization of the ynamide α-carbon atom to the gold-activated alkyne, and final deaurative [1,5]-sulfinylation. This process allows the synthesis of peripherally decorated unconventional 4-sulfinylated pyrroles with broad scope from N-propargyl-tethered ynamides. In contrast, N-homopropargyl-tethered ynamides undergo intramolecular tetradehydro Diels-Alder reaction to provide 2,3-dihydro-benzo[f]indole derivatives. Control experiments and density-functional theory studies were used to study the reaction pathways.
在XPhos金催化剂存在下，开发了一种炔基连接的烯酰胺的区域选择性磺酰基/亚磺酰基迁移环异构化级联反应。该反应是首例从氮中心到烯酰胺β-碳原子的一般[1,3]-磺酰基迁移，随后烯酰胺α-碳原子进行极性翻转5-内型-环化至金活化的炔烃，最后进行脱金[1,5]-亚磺酰化反应。该过程可从N-炔丙基连接的烯酰胺合成范围广泛的外周修饰非常规4-亚磺酰化吡咯。相比之下，N-高炔丙基连接的烯酰胺发生分子内四脱氢狄尔斯-阿尔德反应，生成2,3-二氢-苯并[f]吲哚衍生物。通过对照实验和密度泛函理论研究来探究反应途径。
