| This paper is on the study of Iron-Sulfur cluster and Co(Ⅱ) complex initiated radical chain nucleophilic substitution reaction (SRN1 Reactions) of aryl halides with different nucleophiles. We studied the influence of initiating reagent, temperature and reaction time and certified that the reactions were occurred by the SRN1 mechanism.As for initiation step, the electron transfer (ET) can be induced by light, electricity, solvated electron or heating et. All these initiated process have been studied in detail. The studies on metal ion stimulated SRN1 Reactions are not so much reported. In order to be widely used in the field of organic synthesis for SRN1 reactions, we are therefore in search of the new suitable reagent for initiating these reactions. This paper describes SRN1 reactions were induced by (Et2N)2[Fe4(SPh) (EFSP) and Co(NH3)6Cl2, as electronic donors, and gets good results.The reaction of α-Bromonaphalene with pinacolone carbanion induced by EFSP and Co(NH3)6Cl2 gives substituted product l-(α-naphthyl)-3,3-dimethyl-2-butanone, also the reaction of α-Bromonaphalene with acetophenone enolate ion gives the expected product α-naphthylacetophenone. When we selecte α-Bromopyridine as aryl halides, EFSP as an electronic donor, Pinacolone Carbanion as nucleophiles, 2,2-dimethyl-5-t-butyl-6-(a-pyridyl)5-ene-3-hexaneione and its enolic form were got. All these reactions were inhibited by m-dinitrobenzene, a well known inhibitor of SRN1 reactions and they did not occur in the absence of Iron-Sulfer cluster and Co( II) complex. All these results let us to propose a SRN1 mechanism in play for the above reactions. And we can indicate that Iron-Sulfur cluster and Co( II) complex, as electronic doners, can stimulated the SRN1 reactions of aryl halides with different nucleophiles.Under the above same conditions, selecting 3-Bromo-N-butyl carbazole as aryl halides and different nucleophiles, We will do further study work for the reaction mechanism.
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