A diastereoselective cobalt-mediated synthesis of benzopyrans using a novel variation of an intramolecular Nicholas reaction in the key cyclisation step: optimisation and biological evaluation 1
of novel intramolecular cyclisation reactions between an organocobalt stabilised cation and a trisubstituted alkene have been accomplished that provide a concise route for the diastereoselective synthesis of a range of functionalised benzopyrans. In addition to the usual Lewis acids employed in the Nicholas reaction our studies have identified several other reagents for effecting the cyclisation reaction
Copper(I)-Catalyzed Hydroalkoxylation/Hydrogen-Bonding-Induced Asymmetric Hetero-Diels-Alder Cycloaddition Cascade: An Approach to Aromatic Spiroketals
作者:Xin Li、Jijun Xue、Chusheng Huang、Ying Li
DOI:10.1002/asia.201101056
日期:2012.5
One thing leads to another: Bis(benzannelated) 5,6‐spiroketal skeletons can be constructed by an efficient cascade process involving an unprecedented CuI‐catalyzed intramolecular alkyne hydroalkoxylation and an asymmetric hetero‐Diels–Alder cycloaddition. The method yields a series of diversely functionalized spiroketals from two readily available open‐chained starting materials in good yields and
A New Copper(I)-Catalyzed Cycloetherification/Acid-Catalyzed Allylic Nucleophilic Substitution for One-Pot Synthesis of 2-Substituted Benzofurans
作者:Jijun Xue、Ying Li、Xin Li、Rui Chen
DOI:10.1055/s-0031-1290767
日期:2012.4
A new copper(I)-catalyzed cycloetherification followed by an acid-catalyzed allylic nucleophilic substitution have been developed for the one-potsynthesis of 2-substituted benzofurans. This one-pot reaction proceeds efficiently under extremely mild conditions with simple and inexpensive catalysts, providing diversely substituted benzofurans in good to excellent yields.