Kai Oberdorf1, Anna Hanft2, Jacqueline Ramler3, Ivo Krummenacher2, Matthias Bickelhaupt4, Jordi Poater5, Crispin Lichtenberg6. 1. University of Wurzburg: Julius-Maximilians-Universitat Wurzburg, Inorganic Chemistry, GERMANY. 2. Julius Maximilians University Würzburg: Julius-Maximilians-Universitat Wurzburg, Inorganic Chemistry, GERMANY. 3. Julius-Maximilians-Universität Würzburg: Julius-Maximilians-Universitat Wurzburg, Inorganic Chemistry, GERMANY. 4. Vrije Universiteit Amsterdam, Theoretical Chemistry, NETHERLANDS. 5. Universitat de Barcelona, Theoretical Chemistry, SPAIN. 6. Julius-Maximilians-Universität Würzburg, Institut für Anorganische Chemie, Am Hubland, 97074, Würzburg, GERMANY.
Abstract
The controlled release of well-defined radical species under mild conditions for subsequent use in selective reactions is an important and challenging task in synthetic chemistry. We show here that simple bismuth amide species [Bi(NAr 2 ) 3 ] readily release aminyl radicals [NAr 2 ] ● at ambient temperature in solution. These reactions yield the corresponding hydrazines, Ar 2 N-NAr 2 , as a result of highly selective N-N coupling. The exploitation of facile homolytic Bi-Pn bond cleavage for Pn-Pn bond formation was extended to higher homologs of the pnictogens (Pn = N-As): homoleptic bismuth amides mediate the highly selective dehydrocoupling of HPnR 2 to give R 2 Pn-PnR 2 . Analyses by NMR and EPR spectroscopy, single crystal X-ray diffraction and DFT calculations reveal low Bi-N homolytic bond dissociation energies, suggest radical coupling in the coordination sphere of bismuth, and reveal electronic and steric parameters as effective tools to control these reactions.
The controlled relen class="Chemical">ase of well-definpan>ed radical species under mild conpan>ditionpan>s for subsequenpan>t use inpan> selective reactionpan>s is anpan> importanpan>t anpan>d challenpan>ginpan>g tpan> class="Chemical">ask in synthetic chemistry. We show here that simple bismuth amide species [Bi(NAr 2 ) 3 ] readily release aminyl radicals [NAr 2 ] ● at ambient temperature in solution. These reactions yield the corresponding hydrazines, Ar 2 N-NAr 2 , as a result of highly selective N-N coupling. The exploitation of facile homolytic Bi-Pn bond cleavage for Pn-Pn bond formation was extended to higher homologs of the pnictogens (Pn = N-As): homoleptic bismuth amides mediate the highly selective dehydrocoupling of HPnR 2 to give R 2 Pn-PnR 2 . Analyses by NMR and EPR spectroscopy, single crystal X-ray diffraction and DFT calculations reveal low Bi-N homolytic bond dissociation energies, suggest radical coupling in the coordination sphere of bismuth, and reveal electronic and steric parameters as effective tools to control these reactions.
Authors: Julia Haak; Julia Krüger; Nikolay V Abrosimov; Christoph Helling; Stephan Schulz; George E Cutsail Iii Journal: Inorg Chem Date: 2022-07-14 Impact factor: 5.436
Authors: Xiuxiu Yang; Edward J Reijerse; Kalishankar Bhattacharyya; Markus Leutzsch; Markus Kochius; Nils Nöthling; Julia Busch; Alexander Schnegg; Alexander A Auer; Josep Cornella Journal: J Am Chem Soc Date: 2022-09-02 Impact factor: 16.383