title: Stereoselective cycloaddition of dibenzoxazepinium ylides to acetylenes and fullerene C60. Conformational behavior of 3-aryldibenzo[b,f]pyrrolo[1,2-d][1,4]oxazepine systems.
abstract: Cycloaddition of dibenzoxazepinium ylides to acetylene carboxylates leads to cis-3-aryl-3,13b-dihydrodibenzo[b,f]pyrrolo[1,2-d][1,4]oxazepinecarboxylates, which smoothly dehydrogenate to the corresponding pyrrole derivatives. The o-bromophenyl-substituted pyrrole, in contrast to the pyrroline analogue, demonstrates atropoisomerism. Stereoselective cycloaddition of dibenzoxazepinium ylides to fullerene C(60) gives rise to fulleropyrrolidines with cis-configuration. Restricted Ph group rotation is found in the phenyl derivative. Only one of two possible atropoisomers is formed in the reaction of o-bromophenyl-substituted ylide with fullerene C(60). Details of cycloaddition and conformational behavior of cycloadducts were studied by DFT computations.
authors.affiliation: Department of Chemistry, Saint Petersburg State University, Universitetskii pr. 26, 198504 St. Petersburg, Russia. alexander.khlebnikov@pobox.spbu.ru
authors.forename: Alexander F
authors.initials: AF
authors.lastname: Khlebnikov
authors.forename: Mikhail S
authors.initials: MS
authors.lastname: Novikov
authors.forename: Petr P
authors.initials: PP
authors.lastname: Petrovskii
authors.forename: Alexander S
authors.initials: AS
authors.lastname: Konev
authors.forename: Dmitrii S
authors.initials: DS
authors.lastname: Yufit
authors.forename: Stanislav I
authors.initials: SI
authors.lastname: Selivanov
authors.forename: Holm
authors.initials: H
authors.lastname: Frauendorf
mesh_terms: D000114:Acetylene / Q000737:chemistry*; D003500:Cyclization; D037741:Fullerenes / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D010077:Oxazepines / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D013237:Stereoisomerism
chemical_list: D037741:Fullerenes; D010077:Oxazepines; C069837:fullerene C60; D000114:Acetylene