Copper-Organic Framework-Derived Porous Nanorods for Chemoselective Hydrogenation of Quinoline Compounds at an Aqueous/Oil Interface

In this work, a Cu-BTC material was first synthesized by a hydrothermal rota-crystallization method using cupric nitrate and benzene-1,3,5-tricarboxylate (BTC) as raw materials. Compared with a conventional hydrothermal method, this route greatly shortened the synthesis time of Cu-BTC to only 2 h. Cu-BTC was then treated under a N-2 atmosphere at different times and temperatures to obtain the derivative Cu/C-x-t with exceptional hydrophobicity (WCA of 146 degrees), where x represents the pyrolysis temperature and t was the pyrolysis time. The size effect of Cu NPs on carbon played a critical role in promoting the reaction efficiency. The thus-synthesized Cu/C-x-t material acted as an excellent catalyst for the quinoline hydrogenation in an aqueous medium. It was found that the catalytic reactivity of Cu/C attained the highest value at 600 degrees C for 2 h; the conversion of quinoline reached 95.2 mol % and the selectivity of 1,2,3,4-tetrahydroquinoline (THQ) was >99% under mild aqueous reaction conditions. This could be attributed to the hydrophobic surface structure of Cu/C-600 and the interaction between Cu nanoparticles and the surface C matrix, to form a special aqueous/oil microenvironment on the surface of the catalyst and to accelerate the interfacial reactions.