Preparation Of Phosphorus-doped Carbon Materials For Catalytic Hydrogenation And Transfer Hydrogenation Of Nitroaromatic

1)We reported that phosphorus-doped carbon nanotubes?P-CNTs?,showing metal-like properties,can efficiently promote metal-free hydrogenation of nitrobenzene?1a?to aniline?2a?using molecular hydrogen?H₂?as reducing reagent under very mild conditions with reaction temperature only 50?C.The kinetics of 1a hydrogenation over P-CNT reveals that the hydrogenation rate of 1a is a first-order dependence to H₂pressure and P-CNT loading level,and zero-order dependence to 1a concentration,demonstrating the rate-determining step of H₂adsorption and activation over P-CNT.The activation energy of P-CNT catalyzed 1a hydrogenation is 43?3 k J mol^-1with the turnover frequency around 3.60?0.12 h^-1at 50?C.In addition to 1a,the general applicability of P-CNT promoted metal-free hydrogenation process is further demonstrated by applying to various functionalized nitroaromatics with widely industrial interests.The P-CNT shows both excellent yields and selectivities to the hydrogenation with respect to reducible,labile,and strong leaving groups on the nitroaromatics molecules.The stability and reusability of the P-CNT demonstrates an up toan eight-time recycling without evident loss of activity and selectivity.In addition to hydrogenation,metal-freecatalytictransfer hydrogenation of 1a is achieved with P-CNT by using diverse hydrogen sources including hydrazine hydrate?N₂H₄?H₂O?,carbon monoxide/water?CO/H₂O?and formic acid/triethyl amine?HCOOH/Et₃N?.2)The reductive coupling amination of nitrobenzene and furfural is mostly based on metal catalysis.In this article,We reported that Phosphorus and Nitrogen co-doped Carbon Materials via hydrothermal carbonization with biomass furfural as carbon source,phytic acid as phosphorus source and urea as nitrogen source,shows high catalytic activity and Catalytic performance of metals.When molecular hydrogen?H₂?is used as a reducing agent,it can effectively promote the reductive coupling amination reaction of nitrobenzene and furfural,at a reaction temperature of only 120?C.The catalyst is synthesized from biomass and used to catalyze hydrogenation of Biomass-based molecules,having great application prospects.Further comparative researchs show that the metal-free catalyst produces a high catalytic efficiency and the selectivity?>90%?for reductive coupling of p-nitrobenzene and furfural to amines.