IRONCYCLOPENTADIENYL MEDIATED 2-ALKYL-2-ARYLPHENYLSULPHONYLACETONITRILE SYNTHESIS

A unique route to the synthesis of 2-alkyl-2-arylphenylsulphonylaceton itriles via the nucleophilic aromatic substitution (SNAr) of chloroare ne cyclopentadienyliron complexes with 2-alkyl phenylsulphonylacetonit riles has been investigated. Reactions of chloroarene complexes (1a-d) with 2-alkyl phenylsulphonylacetonitrile (2a,b) in the presence of K2 CO3 in DMF at room temperature led to the formation of complexes 3a-d and 4a,c,d in good yields. The use of alkylated phenylsulphonylacetoni triles as nucleophiles in the reactions with the p-dichlorobenzene com plex (1e) allowed the formation of the disubstituted complexes (5, 6). Photolytic demetallation provided an efficient route to the liberatio n of the arylated phenylsulphonylacetonitriles 7a-d, 8a,c,d, 9, and 10 .