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has been cited by the following article:

• TITLE: Solvent Free Synthesis of α, á-Bis(substituted-benzylidene)cycloalkanones Using Covalently Anchored Sulfonic Acid on Silica Gel (SiO2-R-SO3H) as an Efficient and Reusable Heterogeneous Catalyst

  AUTHORS: Azizollah Habibi, Enayatollah Sheikhhosseini, Mohammadali Bigdeli, Saeed Balalaie, Elinaz Farrokhi

  KEYWORDS: Crossed-Aldol Condensation, Heterogeneous Catalysis, α, ?-Bis(substituted-benzylidene)cycloalkanones, SiO2-R-SO3H, Solvent-Free

  JOURNAL NAME: International Journal of Organic Chemistry, Vol.1 No.4, December 8, 2011

  ABSTRACT: We wish to report a mild and efficient Crossed-Aldol reaction for the synthesis of α, ?-bis(substituted-ben- zylidene)cycloalkanones in the presence of catalytic amounts of covalently anchored sulfonic acid onto sil- ica gel under heterogeneous and solvent-free conditions. The present methodology offers several advantages such as excellent yields, simple procedure and work up steps, short reaction times and easy recovery of the catalyst. We have also demonstrated that the catalyst can be reused successfully.