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.
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.
Khlebnikov
Alexander F
AF
Department of Chemistry, Saint Petersburg State University, Universitetskii pr. 26, 198504 St. Petersburg, Russia. alexander.khlebnikov@pobox.spbu.ru
Novikov
Mikhail S
MS
Petrovskii
Petr P
PP
Konev
Alexander S
AS
Yufit
Dmitrii S
DS
Selivanov
Stanislav I
SI
Frauendorf
Holm
H
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
D037741:Fullerenes; D010077:Oxazepines; C069837:fullerene C60; D000114:Acetylene