OICC Press Iranian Journal of Catalysis 2345-4865 2 2 2024 02 03 Synthesis of 4,4′-(arylmethylene)bis(1H-pyrazol-5-ols) via multi-component reactions by using silica-bonded sulfamic acid derivatives EN Shekoofeh Tayebi Young Researchers Club, Gachsaran Branch, Islamic Azad University, Gachsaran, Iran. Khodabakhsh Niknam Department of Chemistry, Faculty of Sciences, Persian Gulf University, Bushehr 75169, Iran. Journal Article 2024 02 03 The one-pot, multi-component synthesis of 4,4′-(arylmethylene)bis(1H-pyrazol-5-ols) by tandem Knoevenagel-Michael reaction of phenylhydrazine, ethyl acetoacetate and aldehydes in the presence of silica-bonded N-propylpiperazine sulfamic acid (SBPPSA) as a recyclable solid acid catalyst was reported. SBPPSA showed much the same efficiency when used in consecutive reaction runs.