Synthesis and biocatalytic ene-reduction of Knoevenagel condensation compounds by the marine-derived fungus Penicillium citrinum CBMAI 1186

The chemoselective bioreduction of α,β-unsaturated compounds is an important synthetic tool that can have applications in the synthesis of many fine chemicals and pharmaceutical molecules. The synthesis of aromatic malononitrile derivatives through Knoevenagel condensation by microwave radiation under green chemistry conditions using methanol like solvent, free base and free catalyst is here reported. In addiction the biocatalytic reduction of the C–C double bond of aromatic malononitrile derivatives by whole cells of the marine-derived fungal Penicillium citrinum CBMAI 1186 was also tested. The products catalyzed by the fungus ene-reductase were obtained in very good yields (up to >98%).