Bimetallic Pd?Au/TiO2 Nanoparticles: An Efficient and SustainableHeterogeneous Catalyst for Rapid Catalytic Hydrogen TransferReduction of Nitroarenes

摘要

Anilines are one of the important chemical feedstocks and areutilized for the preparation of a variety of pharmaceuticals, agrochemicals,pigments, and dyes. In this context, the catalytic reduction of nitrofunctionality is an industrially vital process for the synthesis of anilinederivatives. Herein, we report an efficient nanosized bimetallic Pd?Au/TiO2nanomaterial which is proved to be quite efficient for rapid catalytichydrogen transfer reduction of nitroarenes into corresponding amines.Significantly, the reduction process is successful under solvent-free and mildgreen atmospheric conditions. Bimetallic Pd?Au nanoparticles served as theactive center, and TiO2 played as a support in hydrogen transfer from thesource hydrazine monohydrate. Typical results highlighted that the reactionswere very rapid and the products were obtained in good to excellent yields.Significantly, the process was successful in the presence of a very low amountcatalyst (0.1 mol %). Furthermore, the reaction showed good chemoselectivity and compatiblity with double or triple bond, aldehyde, ketone, and ester functionalities on the aromatic ring. Typicalresults indicated the true heterogeneous nature of the Pd?Au/TiO2 nanocatalyst, where the catalyst retained the activity,without loss of its activity.