Iron cyclopentadienyl mediated 2-alkyl-2-arylphenylsulfonylacetonitrile synthesis.

A unique route to the synthesis of 2-alkyl-2-arylphenylsulfonylacetonitriles via the nucleophilic arom. substitution (SNAr) of (chloroarene)cyclopentadienyliron complexes with 2-alkyl phenylsulfonylacetonitriles was studied. Reactions of chloroarene complexes with 2-alkyl phenylsulfonylacetonitrile in the presence of K2CO3 in DMF at room temp. gave I (R1 = H, o-, m-, p-Me; R2 = Et, Bu) in good yields. The use of alkylated phenylsulfonylacetonitriles as nucleophiles in the reactions with the p-dichlorobenzene complex gave I (R1 = CR2(CN)(SO2Ph), R2 = Et, Bu). Photolytic demetalation provided an efficient route to the liberation of the arylated phenylsulfonylacetonitriles.