Ali Hashemi - Department of Chemistry, Payame Noor University (PNU), P.O.Box۱۹۳۹۵-۳۶۹۷, Tehran, Iran
Sayed Hossein Banitaba - Department of Chemistry, Payame Noor University (PNU), P.O.Box۱۹۳۹۵-۳۶۹۷, Tehran, Iran

2-Amino -4,6 -diphenylnicotinonitriles have been synthesized in high yields by condensation of malononitrile, acetophenone, aryl aldehydes and ammonium acetate in the presence of nano silica sulfamic acid as an inexpensive solid acid catalyst at room temperature. Nano silica showed better catalytic activity toward other nano metal oxides such as Fe2O3, TiO2, MgO and ZrO2. The one-pot methodology resulting in excellent isolated yields in short reaction times is characterized by simple work up procedures and efficient recovery and recycling of the ionic liquid, which acts as a promoter.