title: Ruthenium-catalyzed [2 + 2] cycloadditions of bicyclic alkenes with alkynyl phosphonates.
abstract: Ruthenium-catalyzed [2 + 2] cycloadditions of bicyclic alkenes with alkynyl phosphonates were investigated. The phosphonate moieties were found to be compatible with the Ru-catalyzed cycloadditions giving the corresponding cyclobutene cycloadducts in low to excellent yield (up to 96%). Alkynyl phosphonates showed lower reactivity than other heteroatom-substituted alkynes such as alkynyl halides, ynamides, alkynyl sulfides, and alkynyl sulfones and required a higher reaction temperature and much longer reaction time.
authors: Guelph-Waterloo Centre for Graduate Work in Chemistry and Biochemistry, Department of Chemistry, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors: Neil
authors: N
authors: Cockburn
authors: Elham
authors: E
authors: Karimi
authors: William
authors: W
authors: Tam
mesh_terms: D000475:Alkenes / Q000737:chemistry*; D000480:Alkynes / Q000737:chemistry*; D002384:Catalysis; D003500:Cyclization; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D063065:Organophosphonates / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000475:Alkenes; D000480:Alkynes; D009942:Organometallic Compounds; D063065:Organophosphonates; D012428:Ruthenium