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Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
Excited-state antiaromaticity relief in photoactive amine-boranes promotes transfer hydrogenation to electron-poor
1Institute of Organic Chemistry, RWTH Aachen University, 52074 Aachen, Germany. enrique.arpa@rwth-aachen.de.
Abstract:
By means of DFT and multiconfigurational ab initio simulations, this work showcases the potential ability of photoactive amine-boranes to undergo transfer hydrogenation for the reduction of unsaturated compounds. Following absorption of UV-A light, the model amine-borane populates a low-lying triplet state. Then, the reduction of carbon-carbon double bonds proceeds through low activation barriers, one order of magnitude lower than those in the electronic ground state. The crucial role of excited-state antiaromaticity relief in facilitating this process is demonstrated by the noticeably higher barriers shown by non-triplet-antiaromatic amine-boranes for the same transformation. Overall, this work provides new design rules for developing more efficient amine-boranes for light-mediated reduction reactions.
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