Anti-Markovnikov stereoselective hydroamination and hydrothiolation of (hetero)aromatic alkynes using a metal-free cyclic trimeric phosphazene base
作者:Na Zhao、Chengdong Lin、Lirong Wen、Zhibo Li
DOI:10.1016/j.tet.2019.04.075
日期:2019.6
Hydroamination and hydrothiolation are the most efficient and completely atom-economical process to construct important enamine and vinylsulfide intermediates in pharmaceutical and organic chemistry. The cyclic trimeric phosphazene base (CTPB) showed great catalytic activity for the anti-Markovnikov stereoselective hydroamination and hydrothiolation of alkynes in good to excellent yields. A broad
Base-Mediated Selective Synthesis of Diversely Substituted <i>N</i>-Heterocyclic Enamines and Enaminones by the Hydroamination of Alkynes
作者:Megha Joshi、Monika Patel、Rakesh Tiwari、Akhilesh K. Verma
DOI:10.1021/jo300782n
日期:2012.7.6
Regio- and stereoselective alkynylation of various N-heterocycles 1a–l usingpotassium and cesium salts in DMSO is described. Terminal alkynes 2a–k and internal alkynes 4a–f provided the kinetically stable Z-enamines 3a–l and 5a–i in good to excellent yields using KOH at 120 °C. Addition of heterocyclic amines to 1,3- and 1,4-diethynylbenzene 6a–b provided the mixture of E/Z isomers with KOH; however