Herein, we have established a phenalenyl-based molecular scaffold which serves as a potent photoreductant utilizing the empty NBMO in the presence of a base to form a radical anion which, upon photoexcitation, behaves as a stronger reductant and accomplishes the cleavage of strong C−X (X = Cl, Br, I) bonds under milder reaction conditions. The base was found to be involved in a dual role of electron and hydrogen atom donor. Further, the aryl radical formed by the homolysis of C−X bonds in this technique was captured for the C sp2 −C sp2 coupling with unactivated arenes. The photoreductant potency of the phenalenylbased catalytic system was further extended to C−P as well as C−B bond formation reactions. EPR and lifetime studies reveal the formation of a persistent radical having a sufficient lifetime to take part in the reaction by the PET mechanism. Different spectroscopic techniques combined with DFT calculations were utilized for the characterization of active catalytic species and for the elucidation of plausible mechanistic pathways. This not only is the initial report of the application of phenalenyl as a photoreductant but also provides a completely metal-free (alkali and transition metal) approach for the challenging reductive functionalization of aryl halides at room temperature.
The development of versatile and mild methodologies for the C-N bond construction has always been a hot topic of interest in synthetic organic chemistry. In recent years, electrochemistry has emerged...
We have developed an efficient visible light induced copper‐mediated protocol to synthesize conjugated 1,3‐diynes via decarboxylative homocoupling of arylpropiolic acids. A variety of electron‐rich and electron‐deficient acids worked well in this methodology providing desired product upto 99% yield. Detailed mechanistic investigations including UV‐Vis spectroscopy and in‐situ IR experiments have been carried out to elucidate the plausible reaction mechanism. Compared to previously reported thermal strategies, this new pathway occurs at room temperature, employs greener solvent and aerial oxygen as an oxidant.
An operationally simple process has been developed for the synthesis of unsymmetrical amines and α-amino carbonyl derivatives in the absence of a catalyst, ligand, oxidant, or any additives. Contrary to known reductive amination methods, this protocol is amenable to substrates containing other reducible groups. This process effectively results in consecutive cleavage and formation of CÀ N bonds. DFT studies and Hammett analysis provide useful insight into the mechanism. The role of noncovalent interactions as a stabilizing factor have been examined in the protocol. A wide range of alkyl-bromides have been coupled efficiently with a variety of dimethyl anilines to get unsymmetric tertiary amines with yields up to 90%. This methodology was further extended to the synthesis of α-amino carbonyl derivatives with yields up to 93%.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.