putative Mn nitrenoid intermediate Complex 1 was found to be unreactive towards alkenes and alkanes but did participate in reaction with PPh3 to afford the corresponding iminophospine. Goldberg and co-workers reported the isolation of corrolazine-supported nitrenoid 2, which was similarly found to be unreactive towards either olefins or C-H bonds (Figure ). Use of a tetraanionic tetraamido macrocyclic ligand (TAML) enabled the isolation of Mn(V) imido complex 3 (Figure ). Further oxidation to the corresponding Mn(VI) complex was necessary to engender nitrene transfer chemistry. In the context of porphyrin-supported nitrenoids, acylation of Mn(V) nitrido complex 4 with trifluoroacetic anhydride affords Mn(V) nitrenoid 5, which was characterized by 1 H NMR and UV-vis spectroscopies and displays olefin aziridination activity (Figure ). Figure . A small family of Mn(V) nitrenoids has been characterized, including (a) corrole-supported 1, (b) corrolazine-supported 2, and (c) TAML-supported 3. (d) Treatment of Mn(V) nitride 4 with trifluoroacetic anhydride resulted in the observation of porphyrin-supported Mn(V) nitrenoid 5.