142. P. Müller, C. Baud, Y. Jacquier,
     “The rhodium(II)-catalyzed aziridination of olefins with {[(4-nitrophenyl)sulfonyl]imino}phenyl-lambda³-iodane”
     Can. J. Chem. 1998, 76, 738-750.

The aziridination of olefins with {(4-nitrophenylsulfonyl)imino}phenyl-lambda³-iodane, NsN==IPh (1c), in the presence of [Rh₂(OAc)₄] proceeds in yields of up to 85% when the olefin is used in large excess. Under optimized conditions, styrene (4a) is aziridinated with 1 equiv. of NsN==IPh (1c) in 64% yield with 2 mol% of catalyst. The aziridines derived from electron-rich olefins undergo ring-opening under the conditions of the aziridination and afford rearrangement products or pyrrolidines. The aziridination is sterospecific with 1,2-dialkyl- and 1,2-arylalkyl-disubstituted olefins, but nonstereospecific with stilbene.The rho -value for aziridination of substituted styrenes is -0.61. No ring-opened products are observed upon aziridination of vinylcyclopropanes. In the presence of chiral Rh^II catalysts, the aziridination is enantioselective, affording an ee of 73% with cis- β -methylstyrene (4k) and Pirrungs [Rh₂{(R)-(-)-bnp}₄] catalyst. The experimental results are consistent with a one-step mechanism for transfer of the nitrenoid moiety from the catalyst to the olefin.Key words: aziridination, nitrene transfer, rhodium catalysis.

DOI : 10.1139/v98-058 

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