A template consisting of a melamine‐based microporous polymer network was synthesized and utilized as a solid support to stabilize palladium nanoparticles; the resulting Pd/SNW1 material showed good catalytic activity in copper‐free Sonogashira coupling in water. Various aryl iodides were efficiently coupled with arylacetylenes under very low catalyst loadings in an environmentally benign medium. Hot filtration tests confirmed the heterogeneity of the catalyst, which was reused under the optimized conditions without any significant change in its activity. This simple preparation of the catalyst, the stability of the catalyst, product selectivity, and easy recovery and regeneration indicate the possible utilization of this catalytic system in a multitude of catalyzed reactions and industrial processes.

Novel nitrogen-rich triaminopyrimidine based porous organic polymer (TAP-POP), was synthesized via a simple, cost-effective and catalyst-free Schiff base condensation between 2,4,6triaminopyrimidine and terephthalaldehyde in N, N-dimethylformamide. The TAP-POP was characterized by FT-IR, Powder XRD, Solid-state 13 C and 15 N CP-TOSS NMR, TGA, BET, SEM and TEM analyses. This polymer containing lot of basic nitrogen sites, act as efficient heterogeneous base catalysts for the room temperature synthesis of dihydropyrano[3,2-c]chromenes and dihydropyrano[4,3-b]pyranes from aromatic aldehydes, malononitrile and 4-hydroxycoumarin/4-hydroxy-6-methyl-2H-pyran-2one via a one-pot, three component reaction. This TAP-POP was easily recovered by simple filtration and was reused upto five times with only a marginal loss in its catalytic efficiency. cyclization (step 3) forms the pyrano[3,2-c]chromenes/pyrano [4,3-b]pyranes as the desired product. 2 3 4 5 6 7 8

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