Metal-Free Triazine-Based Polymeric Network for Solar-to-Chemical Conversion: An Insight into the Aza-Henry Reaction

Solar light-assisted chemical transformationis one ofthe mostamicable pathways to achieving sustainability. With this aim, herein,we have developed a metal-free triazine-based donor-acceptorpolymeric network (TMP-TAPA) as a photocatalyst for cross-dehydrogenativecoupling reaction with an insight toward the aza-Henry reaction. Variouscharacterization techniques including N-2 physisorption,PXRD, FTIR, and solid-state NMR spectroscopy have been adopted tocharacterize the synthesized TMP-TAPA photocatalyst. The BET methoddemonstrated the existence of microporosity with a surface area of296 m(2)/g in TMP-TAPA. Photocatalytic experiments have beenperformed under a 15 W table lamp, showing a conversion rate of 70%with >99% selectivity in the cross-dehydrogenative coupling reaction.The mechanistic pathway of the reaction has been thoroughly investigated,which was further corroborated by controlled studies in addition toscavenger and substrate studies. The proposed mechanistic pathwayshowed the importance of singlet oxygen species in the photocatalyzedcross-dehydrogenative aza-Henry reaction.