Manganese imido complex

In 1983, Groves demonstrated the stoichiometric aziridination of alkenes from a manganese-imido complex generated in situ from an isolable (porphyrin)man-ganese-nitrido intermediate (Scheme 1) [4]. This reactivity has recently been exploited with success by DuBois, Carreira and coworkers in the context of (salen)manganese-derived systems for the amination of enol ether derivatives (Scheme 2) [5,6,7,8]. Although not isolated, aziridine intermediates are probably involved in these reactions. 

Edwards NY, Eikey RA, Loring MI, Abu-Omar MM (2005) High-valent imido complexes of manganese and chromium corroles. Inorg Chem 44 3700-3708... 

Imido and 0x0 compounds are intermediates in many of the transfers of oxygen atoms and nitrene units to olefins to form epoxides and aziridines, and they are intermediates in many of the insertions of oxygen atoms and nitrene units into the C-H bonds of hydrocarbons to form alcohols and amine derivatives. The enantioselective epoxidation of allylic alcohols (Scheme 13.22) " is the most widely used epoxida-tion process, and the discovery and development of this process was one of the sets of chemistry that led K. Barry Sharpless to receive the Nobel Prize in Chemistry in 2001. The mechanism of this process is not well established, despite the long time since its discovery and development. Nevertheless, most people accept that transfer of the oxygen atom occurs from a titanium-peroxo complex - rather than from an 0x0 complex. Jacobsen s and Katsuki s - manganese-salen catalysts for the enantioselective epoxidations of unfunctionalized olefins, which were based on Kochi s achiral chromium- and manganese-salen complexes, are a second set of... 

Table 3 Manganese Tris(Imido) Complexes Theory Versus Experiments" ...

Most transition metal imido (nitrene) complexes are nucleophilic at nitrogen, but certain species exhibit electrophilic character. Procedures for the catalytic oxyamination and aziridination of alkenes have been developed where imidoosmium and manganese species, respectively, are generated in situ. 

All of the examples described above involve stoichiometric imido transfer to the alkene substrate. A crucial advance in the area of catalytic oxidation was made by Mansuy, who disclosed the first example of catalytic aziridination of alkenes in 1984 [10]. Both iron- and manganese-based porphyrin complexes were found... 

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