Synthesis, structure, and base-catalytic performance of a laminar zinc phosphite-phosphate

Abstract

A two-dimensional zinc phosphite-phosphate [C₃H₆(OH)NH₃][Zn₂(HPO₃)(PO₄)] (1) was hydrothermally synthesized with 2-hydroxypropylammonium cation as the structure-directing agent. This compound has been characterized by single-crystal X-ray diffraction, IR spectroscopy, and powder X-ray diffraction (XRD). Its microporous framework is constructed by ZnO₄, PO₄, and HPO₃ tetrahedral building blocks with 3, 4, and 6-ring channels. With 1 as base catalytic support, the Knoevenagel condensation reaction of benzaldehyde and ethyl cyanoacetate gives a yield of 59%.

Keywords:

• Zinc phosphite-phosphate
• Layered compound
• Inorganic microporous framework
• Solid base catalyst
• Structure and characterization

Acknowledgments

The authors thank the Natural Science Foundation of China (Grant nos. 21053001, 20701014), Fundamental Research Funds for the Central Universities (Grant no. 2009ZM0030), Guangdong student and SRP program for financial support and Prof. Tong Chun Kuang (Analytical and testing center of SCUT) for the collection of crystal data.