2,2'-Methylenebibenzimidazole-Based Hyper-Cross-Linked Polymer-Supported-Iridium Complex: A Recyclable Metal-Polymer Ligand Bifunctional Catalyst for the Auto-tandem Synthesis of N-Methyl Tertiary Amines from Imines and Methanol.

A metal-polymer ligand bifunctional catalyst Cp*Ir@HCPs-(2,2'-CH2BiBzlmH2) was designed and synthesized by the coordinative immobilization of [Cp*IrCl2] on HCPs-(2,2'-CH2BiBzlmH2). In the presence of a catalyst (1 mol % Ir) and Cs2CO3 (0.3 equiv), a series of N-methyl tertiary amines were obtained from imines and methanol via autotandem transfer hydrogenation/N-methylation. More importantly, the catalyst could be recycled without an obvious loss of activity during six cycles. Apparently, the designed catalyst combines the advantages of both homogeneous and heterogeneous catalysts.