enaminones was achieved to access naphtho[1,8-bc]pyrans by oxidative annulation to internal alkynes. 1-Naphthols might be formed as the only products, depending on the steric and/or electronic environment around the aroyl moiety of the aryl enaminones or the electronic impact from the alkynes. With propargyl alcohols as the masked terminal alkynes, aryl enaminones underwent rhodium(III)- or rhodium(I)-catalyzed
铑 (III) 催化的芳基烯胺酮的三 C-H 键活化通过氧化环化成内部炔烃来获得萘并[1,8- bc ]吡喃。1-萘酚可能作为唯一的产物形成,这取决于芳基烯胺酮的芳酰基部分周围的空间和/或电子环境或来自炔烃的电子影响。使用炔丙醇作为掩蔽的末端炔烃,芳基烯胺酮经历铑 (III) 或铑 (I) 催化的内部烯基 C-H 键活化以提供官能化的丁-2-烯-1,4-二酮。所得萘并[1,8- bc ]吡喃具有高荧光,可通过氯化、溴化和二氟甲基化进一步转化,证明了合成方案的潜在实用性。
An aerobic [2 + 2 + 2] Cyclization via Chloropalladation: From 1,6-Diynes and Acrylates to Substituted Aromatic Carbocycles
A Pd-catalyzed aerobic [2 + 2 +2] cyclization of 1,6-diynes and acrylates proceeding through a chloropalladation process has been developed. Polysubstituted five-membered aromatic carbocycles/heterocycles were obtained in good to excellent yields. The results of the mechanistic study are consistent with the proposed reaction mechanism.
Copper-catalyzed intramolecular aryl-bicyclization of diynes with diaryliodonium salts via vinyl cations
作者:Guohua Wang、Chao Chen、Jing Peng
DOI:10.1039/c6cc05735g
日期:——
A novel protocol for synthesis of polycyclic compounds from linear diynes and diaryliodonium salts has been realized. The reaction proceeded through Cu-catalyzed arylation of alkyne to generate vinyl carbocation intermediates...