Unveiling Heterogeneous Catalytic Potential of Distinctly Coordinated Polymers Toward Henry and Morita‐Baylis‐Hillman Reactions

Abstract

Three 1D coordination polymers (CPs), {[CuL2(H2O)] ⋅ (H2O)3}n (1) {[CoL2(H2O)2] ⋅ (H2O)}n (2) and {[NiL2(H2O)] ⋅ (H2O)3}n (3), (L1=N‐nicotinoylglycinato) have been synthesized by adopting a solvothermal reaction strategy and characterized through several spectral techniques i. e., elemental analyses, FT‐IR, TGA, EDX, DSC, AAS, and PXRD. X‐ray single crystal analysis revealed the 5‐, 6‐ and 7‐coordinated structures respectively for CPs 1, 2 and 3 wherein, L1 connects the metal ions in a bridging mode. The CPs entail H‐bonding, π–π stacking along with other non‐covalent interactions and expand into 3D supramolecular networks. Further, FESEM and HRTEM provided morphological insight for 1–3 and aid in obtaining interplanar spacings. CPs 1–3 possessing distinct coordination numbers and good thermal stability have been subjected to catalysis after optimization and notably, these serve as efficient, easy to work up, and reusable porous heterogeneous catalysts for Henry and Morita‐Baylis‐Hillman (MBH) reactions with reasonably good yields (97–93 %). Remarkably, catalyzed by 1–3 can be reused at least seven times for the Henry reaction and six times for the MBH reaction, retaining their catalytic efficiency. Relative catalytic efficacy toward the Henry and MBH reactions follows the order 1>2>3. Present findings are based on a rational approach of varying coordination number (5, 6 and 7) and metal ions [Cu(II), Co(II) and Ni(II)] respectively in 1–3 having structural evidence and examine their catalytic performances for typical Henry and MBH reactions.