Palladium-Catalyzed Cyanations of Aryl Imidazolylsulfonates with K4 [Fe(CN)6 ]: A Pragmatic Approach to Benzonitriles from Phenols.

A general Pd-catalyzed approach for the conversion of phenols into benzonitriles via aryl imidazolylsulfonates with a non-toxic cyanide source, potassium ferrocyanide, has been developed. Salient features of this method include low palladium precatalyst loadings (as low as 1.0 mol% total Pd), mild reaction conditions, and environmentally benign by-products compared to other (pseudo)halide aryl electrophiles. The initial scope of the reaction on a range of phenolic precursors is demonstrated including a one-pot, two-step approach to convert phenols directly into benzonitriles. [ABSTRACT FROM AUTHOR]