Nitrogen‐Doped Graphene‐Supported Iron Catalyst for Highly Chemoselective Hydrogenation of Nitroarenes

Abstract

An itrogen-doped graphene-supported iron catalyst was used for the first time in the hydrogenation of aseries of nitroarenes to give the corresponding amines with excellent activity and chemoselectivity under mild reactionc onditions. Physicochemical characterization of the catalyst by transmission electron microscopy,X -ray diffraction, X-ray photoelectrons pectroscopy,a nd Mçssbauers pectroscopy revealed the formation of iron particles with an iron oxide core and am etallic iron shell that were coated by af ew layers of nitrogen-doped graphene. The uniques tructure of FeN x /C in the catalyst was provent o contributetothe hydrogenation activity.Heterogeneous catalytic hydrogenation plays an important role in achieving more environmentally benign and atom-economic processes in the chemical industry. [1] Noble metals such as Ru, Rh, Pd, Pt, Ir,a nd Au and base metals such as Co, Ni, Fe, and Cu have both been widely utilized as active sites in supported heterogeneousc atalysts for the hydrogenation of various unsaturated functional groups. [2] In terms of metal-involved heterogeneous hydrogenation reactions, the Horuiti-Polanyi mechanism,i nw hich the metallic atoms first catalyze scissiono ft he HÀHb ond in H 2 anda dsorb the dissociated hydrogen atoms, is generally accepted andh as been provenb y modernp hysicochemical characterization techniques andf irstprinciples calculations. [3] Consequently,ametal that maintains its metallic state insteado fa dopting an oxidized state is required for HÀHs cission and the adsorption of Ha toms. To reach this goal, aw ell-known process in the heterogeneous catalysis field has been established,t hat is,H 2 -TPR (temperature-programmed reduction), by which the minimum temperature for complete reduction of the metal oxidesi nto metallic atoms is determined to prepare metal catalysts. [4] By contrast, [a] Dr.Supporting Information and the ORCID identification number(s) for the author(s) of this article can be found underh ttps://doi.

Metal‐2D Semiconductor Hybrid Nano‐Structure Catalyst: A New Frontier of Heterogeneous Catalysis

“…[44] It showed that excellent performance and improvement could be achieved by using graphene materials as catalyst supports in various reactions. [45] However, the preparation process of GO is demanding.…”

“…According to recent research, GO not only has a larger specific surface area than CNTs, but also uses the surface area more efficiently because of the special two‐dimensional planar microstructure [44] . It showed that excellent performance and improvement could be achieved by using graphene materials as catalyst supports in various reactions [45] . However, the preparation process of GO is demanding.…”

A Concise Route to Cyclic Amines from Nitroarenes and Ketoacids under Iron‐Catalyzed Hydrosilylation Conditions

“…[4] One of the well-established methodology of reduction of nitroarenes was described by Béchamp with more than a stoichimoetric amount of iron powder in acidic conditions. [5] More efficient and chemoselective iron-catalyzed methodologies involving hydrosilylation, [6] hydrogenation, [7] hydrogen transfer [8] or other reductants [9] were also recently reported. Cascade reactions involving iron-catalyzed reduction of nitroarenes were also reported.…”