Single atom catalysts (SACs) are potential heterogeneous catalysts attributed in the field of catalysis owing to the advantage of both homogeneous and heterogeneous system with atomically dispersed mono nuclear metal centers on the solid supports. Herein, we developed SACs heterogeneous catalysts by polymerization of active homogenous picolinylhydrazide ligand based iridium (Ir) metal complex and PN3P pincer based nickel (Ni) metal complex. The key aspects of such catalysts provide a stabilisation as formed single atoms against migration and agglomeration that triggered by strong covalent C-C bond linkage with active catalyst and polymer. SACs Ir catalyst shows remarkable selectivity (>93%) towards glycerol (GA) to lactic acid (LA) conversion with highest TON up to 9.7×106 and TOF of 205833 h-1 up to date. This single atom catalyst offers very good stability and recyclability for several cycles despite of the presence of aqueous and alkali medium. Whereas Ni SACs shows excellent selectivity for Furfural and levulinic acid conversion to furfuryl alcohol and γ-valerolactone respectively in excellent TON and TOF.