علیرضا حسنی نژاد

3-Aminopropylated silica gel is introduced as an ef?cient, reusable, and thermally stable heterogeneous catalyst for tandem Knoevenagel–Michael reaction of 1-phenyl-3methyl-5-pyrazolone with aldehydes. Short reaction times, mild reaction conditions, ease of recovery, and catalyst reusability make this method a new, economical, and waste-free chemical process for the ef?cient synthesis of bis(pyrazolyl)methanes.