The Lewis acidic nature of both {[Zn4(µ3-OH)2(d-2,4-cbs)2(H2O)4].5H2O}n(Zn-CBS) and its ZnO nanostructures (ZnO_1, 3D microflower; ZnO_2, 3D polyhedron; and ZnO_3, 1D nanorod) was explored for the comparative study of the C–C and C-N bond forming reactions, such as Knoevenagel condensation, Friedel–Crafts alkylation and Strecker reaction, with various substrates. Notably, the nanorod (ZnO_3) is found to be an exceptionally efficient heterogeneous catalyst in comparison to its parent Zn-CBS for the Knoevenagel condensation reaction showing 100% conversion in 15 min with only 2 mol% catalyst in methanol at 25 °C. Similar catalytic results were obtained in the multicomponent Strecker reaction where ZnO_3 showed an enhanced catalytic activity in water as compared to Zn-CBS. However, for the Friedel–Crafts alkylation reaction, Zn-CBS was better than ZnO_3. These highly efficient catalysts are recyclable for three consecutive runs without any notable change in the catalytic activity. Their mechanism of action for all three reactions is also explained. Graphical Abstract: [Figure not available: see fulltext.] © 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.