An unprecedented protocol has been developed for the efficient synthesis of substituted tetrahydropyrans via a bismuth-promoted Prins cyclization of imines with homoallyl alcohols.In the presence of 40 mol%BiCl_(3),a ...An unprecedented protocol has been developed for the efficient synthesis of substituted tetrahydropyrans via a bismuth-promoted Prins cyclization of imines with homoallyl alcohols.In the presence of 40 mol%BiCl_(3),a wide variety of imines react smoothly with homoallyl alcohols at room temperature to give the corresponding 4-chlorotetrahydropyran derivatives in good to excellent yields.展开更多
The Prins cyclization of enol ethers has been realized by employing BiX3 （or FeX3） as catalyst and TMSX （X = Br, C1） as the halogen source. The presence of a tiny amount of water in the solvent dichloromethane pla...The Prins cyclization of enol ethers has been realized by employing BiX3 （or FeX3） as catalyst and TMSX （X = Br, C1） as the halogen source. The presence of a tiny amount of water in the solvent dichloromethane played a key role for the reaction to proceed. The reaction is believed to be catalyzed by Lewis acid-assisted Bronsted acids, which were generated in situ from MX3 and water in the solvent.展开更多
基金We are grateful for the financial support from the National Natural Science Foundation of China(No.21202154)Nanjing Institute of Technology Fund for Talents(No.YKJ201329)Nanjing Institute of Technology and the University of Science and Technology of China.
文摘An unprecedented protocol has been developed for the efficient synthesis of substituted tetrahydropyrans via a bismuth-promoted Prins cyclization of imines with homoallyl alcohols.In the presence of 40 mol%BiCl_(3),a wide variety of imines react smoothly with homoallyl alcohols at room temperature to give the corresponding 4-chlorotetrahydropyran derivatives in good to excellent yields.
基金Supporting information for this article is available on the WWW under http：//dx.cioi.org/10. 1002/cjoc.201100659 or from the author.Acknowledgement The authors thank the National Natural Science Foundation of China （No. 20772053） and the Fundamental Research Funds for the Central Universities forfinancial support.
文摘The Prins cyclization of enol ethers has been realized by employing BiX3 （or FeX3） as catalyst and TMSX （X = Br, C1） as the halogen source. The presence of a tiny amount of water in the solvent dichloromethane played a key role for the reaction to proceed. The reaction is believed to be catalyzed by Lewis acid-assisted Bronsted acids, which were generated in situ from MX3 and water in the solvent.
