An Efficient Method for Knoevenagel Condensation Catalyzed by Tetrabutylammonium hexatungstate [TBA]₂[W₆O₁₉] as Novel and Reusable Heterogeneous Catalyst

Abstract

Tetrabutylammonium hexatungstate [TBA]₂[W₆O₁₉] has been efficiently used as catalyst for the synthesis of electrophilic alkenes via the Knoevenagel condensation reaction of aromatic aldehydes with malononitrile. The catalyst shows high catalytic activity with good to excellent yields of the desired products. Moreover, the catalyst could be recycled three times without noticeably decreasing the catalytic activity.

Keywords:

• heterogeneous catalysis
• Knoevenagel condensation
• tetrabutylammonium hexatungstate [TBA]₂[W₆O₁₉]

Acknowledgments

The author is thankful to Islamic Azad University, Mashhad Branch for financial support.