Remarkably Efficient Olefin Aziridination Mediated by a New Copper(II) Complex

The structurally characterized copper complex [( i -Pr 3 TACN)Cu(O 2 CCF 3 ) 2 ] ( 1 ) mediates nitrene transfer from PhINTs to olefins to form N -tosylaziridines in good to excellent yields, in catalytic amounts (0.5 mol %) 1 order of magnitude less than is required for other copper catalysts, such as [Cu(acac) 2 ]. Nitrene transfer reactivity has also been observed with substituted styrenes, internal and terminal aliphatic olefins, and sulfides, suggesting that 1 may be a general nitrene transfer catalyst for use on organic synthesis.