Two-carbon ring expansion of cyclobutanone skeletons by nickel-catalyzed intermolecular alkyne insertion
摘要:
The reaction of cyclobutanone with an alkyne in the presence of a nickel(0) catalyst formally achieves intermolecular alkyne insertion between the carbonyl carbon and the a-carbon of a cyclobutanone, providing a six-membered carbocyclic skeleton. (c) 2006 Elsevier Ltd. All rights reserved.
Cyclobutanones reacted with alkynes in the presence of nickel(0) catalysts to produce cyclohexenones. Oxidativecyclization of the carbonyl group of the cyclobutanone and the alkyne with the nickel(0) was followed by beta-carbon elimination from the resulting oxanickelacyclopentene and subsequent reductiveelimination. This reaction achieves a formal alkyneinsertion between the carbonyl carbon and