Regio- and Stereoselective Coupling of Heteroaryl-Substituted Alkynes: New Insights into the Mechanism of Zirconium-Mediated Cyclodimerization of Alkynes and a Facile Route to 3-Methylenecyclobutenes
作者:Zhiquan Song、Yuxue Li、Meina Liu、Liqing Cong、Yuanhong Liu
DOI:10.1021/om060505j
日期:2006.10.1
The cyclodimerization of (2-pyridyl)alkynes tethered with an amino group mediated by zirconium was achieved cleanly under controlled reaction conditions. This methodology provided an efficient route for the synthesis of tetrasubstituted cyclobutenes with high regio- and diastereoselectivity when the reaction was quenched by water. However, by quenching with saturated NaHCO3 solution, a 3-methylenecyclobutene
Palladium-Catalyzed Dearomative Cyclocarbonylation by CN Bond Activation
作者:Hui Yu、Guoying Zhang、Hanmin Huang
DOI:10.1002/anie.201504805
日期:2015.9.7
intramolecular cyclocarbonylation of allylamines. [Pd(Xantphos)I2], which features a very large bite angle, has been found to facilitate the rapid carbonylation of azaarene‐substituted allylamines into bioactive quinolizinones in good to excellent yields. This transformation represents the first dearomative carbonylation and is proposed to proceed by palladium‐catalyzed CNbondactivation, dearomatization