%0 Journal Article %T The aromatic Claisen rearrangement of a 1,2-azaborine %+ Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM) %+ Boston College (BC) %A Robichaud, Hannah %A Ishibashi, Jacob %A Ozaki, Tomoya %A Lamine, Walid %A Miqueu, Karinne %A Liu, Shih-Yuan %< avec comité de lecture %@ 1477-0520 %J Organic & Biomolecular Chemistry %I Royal Society of Chemistry %V 21 %N 18 %P 3778-3783 %8 2023-05-10 %D 2023 %R 10.1039/d2ob02186b %Z Chemical Sciences %Z Chemical Sciences/Theoretical and/or physical chemistryJournal articles %X The first aromatic Claisen rearrangement of a 1,2-azaborine is described along with a quantitative kinetic comparison of the reaction of the azaborine with its direct all-carbon analogue. The azaborine A rearranged in a clean, regioselective fashion and reacted faster than the all-carbon substrate B at all temperatures from 140-180 °C. Activation free energies were extracted from observed first-order rate constants (A: ΔG‡298K = 32.7 kcal mol−1; B: ΔG‡298K = 34.8 kcal mol−1) corresponding to a twenty fold faster rate for A at observed reaction temperatures. DFT calculations show that the rearrangement proceeds via a concerted six-membered transition state and that the electronic structure of the BN and CC rings is mostly responsible for the observed regioselectivity and relative reactivity. %G English %2 https://univ-pau.hal.science/hal-04094407/document %2 https://univ-pau.hal.science/hal-04094407/file/Hal_Claisen-Rearrangment.pdf %L hal-04094407 %U https://univ-pau.hal.science/hal-04094407 %~ CNRS %~ UNIV-PAU %~ IPREM %~ INC-CNRS %~ IPREM-CAPT %~ ANR %~ UPPA-OA