Organoiron porphyrins

Six-coordinate organoiron porphyrin nitrosyl complexes, Fe(Por)(R)(NO), were prepared from Fe(Por)R (Por = OEP or TPP R = Me, n-Bu, aryl) with NO gas. The NMR chemical shifts were typical of diamagnetic complexes, and the oxidation state of iron was assigned as iron(ll). ... 

Nitric oxide (NO) reacts with organoiron(IIl) porphyrins to form six-coordinate adducts, Fe(Por)(R)(NO), Other small molecules (Oi. SO2. CO) react by insertion into the Fe—C bond, although the nature of the reaction and the stability of the products varies greatly with both the molecule itself and the organoiron group. 

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