Titania Nanoparticle Catalysed N‐Alkylation of Amines by Hydrogen Auto‐Transfer Mechanisms

Abstract

Unlike well‐defined homogenous metal complex catalysts, no distinct heterogeneous catalysts are available for hydrogen auto‐transfer or borrowing hydrogen methodologies. Alternatively, a variety of noble metals, base metals, and bimetallic systems supported on various metal oxides are scrutinized for this purpose, mainly by modulating the ability of metals and supports in a multistep reaction. Herein, we demonstrate that pristine defect‐induced titania nanoparticle catalyst is an efficient and recyclable heterogeneous catalyst for the preparation of N‐alkylated products (>90 %) in the absence of expensive hydrogen source, costly ligands, additives, or costly metals under greener conditions. Furthermore, the nano‐sized titania catalyst tolerates functional groups with high yields. In addition, the ‐alkylation of aniline affords the corresponding alkylated products in d yields with long aliphatic alcohols. Finally, the results of the control tests show that a process of Hydrogen Auto transfer is responsible for carrying out the reaction.