Publication 139
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I. Nägeli, C. Baud, G. Bernardinelli, Y. Jacquier, M. Moraon, P. Müller,
“Rhodium(II)-Catalyzed CH Insertions with {[(4-Nitrophenyl)sulfonyl]imino}phenyl-λ3-iodane”
Helv. Chim. Acta 1997, 80, 1087-1105.
The [Rh2(OAc)4]-catalyzed decomposition of {[(4-nitrophenyl)sulfonyl]imino}phenyl-λ3-iodane (NsN?IPh) resulted in formal insertions into CH bonds, activated by phenyl or vinyl groups, or by O-substituents. Scope and limitations of the reaction were investigated. Yields of up to 84% were achieved in the most favorable cases. Yields were enhanced by electron-releasing substituents and decreased by steric hindrance. Aziridination competed with allylic insertion with olefinic substrates. The insertion reaction proceeded with retention of configuration. With chiral RhII catalysts, a modest asymmetric induction was observed. A mechanism involving direct insertion by a Rh-complexed nitrene into the CH bond is proposed.
DOI : 10.1002/hlca.19970800407
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