Cross-Coupling of Phenyl Halides with Sodium Dicyanomethanide in the Presence of Tetraki(triphenyphosphine)palladium

Abstract

1-Aromatic substituted imidazoles were synthesized by a convenient modified process. A crosscoupling reaction of phenyl halides with sodium dicyanomethanide has been achieved to produce the arylmalononitriles coupling products as zwitterionic precursors in high yields by using catalytic tetrakis(triphenyphosphine)palladium under mild conditions. The molecular structure was characterized by ¹H NMR and ¹³C NMR spectra, LC-MS and GC-MS. It was found that the products can be easily separated with high yields. When electron-withdrawing groups were employed, substituted phenyl bromide can also be used as the precursors to produce good yield of 87 %. This provides an efficient and practical strategy for the preparation of substituted terminal phenyl malononitriles.