Cobalt-Catalyzed Intramolecular [4 + 2] Cycloaddition of Cyclopropyl-Capped Dienes with Alkynes/Alkenes/Allene and
Liyan Kan1, Yi Zhou1, Ling-Quan Kong1
1Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China.
Abstract:
A cobalt-catalyzed intramolecular [4 + 2] cycloaddition of cyclopropyl (CP)-capped dienes with ynes/enes/allene was reported, providing an efficient method toward a spiro[2.5]octene ring system found in natural products, such as illudin. The [4 + 2] cycloadducts can be converted into other compounds via CP chemistry. This reaction can also be catalyzed by Ni. A density functional theory study on the reaction mechanisms is also reported here.
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