Wu YT Linden A Siegel JS 2005 [reaction: see text] Fluoranthene 2 and heptacycle 3 are easily accessible from the reaction of diyne 1 and norbornadiene (NBD) in the presence of the rhodium catalyst. The unusual [(2+2)+(2+2)] adduct 3 was confirmed by the X-ray crystal structure analysis. https://sonar.ch/global/documents/14229 eng info:eu-repo/semantics/altIdentifier/doi/10.1021/ol0514799 info:eu-repo/semantics/altIdentifier/pmid/16178531 Organic letters. - 2005 Physical and Theoretical Chemistry Organic Chemistry Biochemistry Formal [(2+2)+2] and [(2+2)+(2+2)] nonconjugated dienediyne cascade cycloadditions. http://purl.org/coar/resource_type/c_6501