Lewis Acid Catalyzed Electrophilic Aminomethyloxygenative Cyclization of Alkynols with N,O-Aminals
Anrong Chen1, Houjian Yu1, Jiaqi Yan1
1Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, Center for Excellence in Molecular Synthesis , University of Science and Technology of China , Chinese Academy of Sciences, Hefei 230026 , P.R. China.
Abstract:
Lewis acid enables the electrophilic carbooxygenative cyclization of alkynols with N,O-aminals. The new process proceeds efficiently under very mild conditions via a pathway that is opposite to classical carbo-metalation. These reactions exhibit broad substrate generality and functional group compatibility, leading to a wide variety of 5-8-membered oxacycles bearing diverse functional groups. The cyclization products can be elaborated via simple functional group transformations to generate synthetically useful oxacycles.
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