title: Light-induced coumarin cyclopentannelation.
abstract: [reaction: see text] Whereas cyclopentenylcarbenes resulting from photocycloaddition of 4-alk-1-ynylcoumarins to 2,3-dimethylbut-2-ene undergo tandem cyclization to hitherto unknown tetracyclic (4-hetera)cyclopent[b,c]acenaphthylenes, the corresponding cyclopentenylnitrenes stemming from 4-cyanocoumarins and the same alkene are converted into tricyclic imines via H-abstraction.
authors.affiliation: Institute of Organic Chemistry, University of Hamburg, D-20146 Hamburg, Germany.
authors.forename: Marko
authors.initials: M
authors.lastname: Soltau
authors.forename: Maren
authors.initials: M
authors.lastname: Göwert
authors.forename: Paul
authors.initials: P
authors.lastname: Margaretha
mesh_terms: D000475:Alkenes / Q000737:chemistry; D002384:Catalysis; D003374:Coumarins / Q000737:chemistry*; D003500:Cyclization; D003517:Cyclopentanes / Q000138:chemical synthesis* / Q000737:chemistry; D007097:Imines / Q000737:chemistry; D008027:Light; D015394:Molecular Structure
chemical_list: D000475:Alkenes; D003374:Coumarins; D003517:Cyclopentanes; D007097:Imines