An efficient basic catalyst based on a new germanium coordination complex

The replacement of liquid bases by solid base catalysts is a crucial requirement for sustainable industrial processes. The use of heterogeneous catalysts can improve the overall atom catalytic efficiency of reactions and facilitate the organic separation process. Here, we report the synthesis and characterization of a germanium coordination complex Ge(C3H6ONH2)2(OH)2 (1). Complex 1 is obtained by hydrothermal synthesis and is crystallized in the monoclinic system, space group P21/c with a = 10.250 (2) Å, b = 9.810 (2) Å, c = 10.360 (2) Å, and β = 100.70 (3)°. Single crystal data indicate that the Ge4 + ion has octahedral coordination geometry surrounded by two 2-hydroxypropylammine molecules. Knoevenagel condensation of benzaldehyde and ethyl cyanoacetate is carried out with compound 1 as solid catalytic support in ethanol at 333 K. Experimental results indicate that it is an efficient base catalyst. The reaction gives a 98% yield for the condensation product.