Pyridinic-nitrogen on ordered mesoporous carbon: A versatile NAD(P)H mimic for borrowing-hydrogen reactions

Metal-free carbonaceous materials are an emerging class of heterogeneous catalysts for sustainable chemistry. However, designing such catalytic materials with unique properties for specific organic transformations remains a challenge due to an inadequate understanding of their active sites. Herein, we report our studies on the use of nitrogen-doped ordered mesoporous carbons as a biomimetic novel heterogeneous catalyst for the borrowing-hydrogen or hydrogen-auto-transfer class of cascade reactions. These redox neutral processes have gained prominence owing to their high atom economy and sustainability. Our experimental investigations, supported by computer modelling, show that the local nitrogen environment, i.e., the benzannulated pyridine substructures on the edges/defects of the carbon matrices, play a critical role as catalytic hydrogen shuttles in borrowing-hydrogen reactions mimicking the role of the NAD(P)+/NAD(P)H redox couple.