Heck and Oxidative Boron Heck Reactions Employing Pd(Ii) Supported Amphiphilized Polyethyleneimine-Functionalized Mcm-41 (Mcm-41@Apei-Pd) As an Efficient and Recyclable Nanocatalyst Publisher



Motevalizadeh SF¹ ; Alipour M² ; Ashori F³ ; Samzadehkermani A⁴ ; Hamadi H⁵ ; Ganjali MR^{6, 7} ; Aghahosseini H⁸ ; Ramazani A⁸ ; Khoobi M^{2, 9} ; Gholibegloo E⁸
Source: Applied Organometallic Chemistry Published:2018

Abstract

A novel nanocatalyst was developed based on covalent surface functionalization of MCM-41 with polyethyleneimine (PEI) using [3-(2,3-Epoxypropoxy)propyl] trimethoxysilane (EPO) as a cross-linker. Amine functional groups on the surface of MCM-41 were then conjugated with iodododecane to render an amphiphilic property to the catalyst. Palladium (II) was finally immobilized onto the MCM-41@PEI-dodecane and the resulted MCM-41@aPEI-Pd nanocatalyst was characterized by FT-IR, TEM, ICP-AES and XPS. Our designed nanocatalyst with a distinguished core-shell structure and Pd2+ ions as catalytic centers was explored as an efficient and recyclable catalyst for Heck and oxidative boron Heck coupling reactions. In Heck coupling reaction, the catalytic activity of MCM-41@aPEI-Pd in the presence of triethylamine as base led to very high yields and selectivity. Meanwhile, the MCM-41@aPEI-Pd as the first semi-heterogeneous palladium catalyst was examined in the C-4 regioselective arylation of coumarin via the direct C-H activation and the moderate to excellent yields were obtained toward different functional groups. Leaching test indicated the high stability of palladium on the surface of MCM-41@aPEI-Pd as it could be recycled for several runs without significant loss of its catalytic activity. Copyright © 2017 John Wiley & Sons, Ltd.