| Summary: | The immobilization of 2-phenyl-2-((3(tryethoxysicyl)propyl)imino)ethanol (<b>HL1</b>) and 4-methyl-2-(((3(triethoxysilyl)propyl)imino)methyl)phenol (<b>HL2</b>) on MCM-41 afforded the respective ligands <b>HL1</b>-MCM-41 (<b>HL3</b>) and <b>HL2</b>-MCM-41 (<b>HL4</b>). The treatment of complexes Pd(<b>L1</b>)<sub>2</sub> and Pd(<b>L2</b>)<sub>2</sub> with MCM-41 afforded the immobilized complexes (Pd(<b>L1</b>)<sub>2</sub>)-MCM-41 (<b>1</b>) and (Pd(<b>L2</b>)<sub>2</sub>)-MCM-41 (<b>2</b>) respectively. Separately, the reactions of <b>HL3</b> and <b>HL4</b> with Pd(NCMe)<sub>2</sub>Cl<sub>2</sub> produced the immobilized complexes Pd(<b>HL3</b>)Cl<sub>2</sub> (<b>3</b>) and Pd(<b>HL4</b>)Cl<sub>2</sub> (<b>4</b>) respectively. The immobilized compounds were characterized by FT-IR, Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), energy-dispersive X-ray (EDX), Thermogravimetric Analysis (TGA) and X-ray Powder Diffraction (XRD). All the complexes (<b>1</b>⁻<b>4</b>) formed active catalysts in the methoxycarbonylation of 1-hexene to give linear and branched esters. The catalysts were recycled four times without the loss of catalytic activity. Hot filtration experiments established the absence of leaching, and the heterogeneous nature of the active species was derived from mercury drop experiments.
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