880551-38-2Relevant academic research and scientific papers
Nickel-catalyzed [4 + 2 + 2]-type annulation reaction of cyclobutanones with diynes and enynes
Ashida, Shinji,Murakami, Masahiro
experimental part, p. 885 - 893 (2009/04/10)
In the presence of a nickel(0) catalyst, cyclobutanones reacted with diynes to produce bicyclic eight-membered ring ketones. Cyclobutanones acted as a C4 unit in the formal [4 + 2 + 2]-type annulation reaction, which proceeded through a ring-expansion of a spirocyclic seven-membered oxanickelacycle to a nine-membered nickelacycle via β-carbon elimination. A similar annulation reaction was also examined with enynes.
