This communication report knoevenagel cyclo-condensationusing hydrotalcites prepared using various methods. Further, the hydrotalcite providing maximum yields was used for the synthesis of 3 acetyl coumarin. In this multi-component reaction the yields obtained with Mg-Al-CO3 LDH was 94% and with the unreported Ca-Al-CO3 LDH was 93% respectively. The reaction conditions being 2 wt% catalysts at 800C for only 90 minutes. The main benefit of the present work is reduction of time along with the catalyst used is environmentally benign, recyclable and easy to work up procedure using water as green solvent. The catalysts as well the products were subjected to various characterization being X-RD, TGA, FT-IR, SEM, NMR, Mass, and basicity respectively.