A Highly Sterically Encumbered Boron Lewis Acid Enabled by a Organotellurium-based Ligand

Chemistry. 2024 Apr 16:e202401231. doi: 10.1002/chem.202401231. Online ahead of print.ABSTRACTLewis acidic boron compounds are ubiquitous in chemistry due to their numerous applications, yet tuning and optimizing their properties towards different purposes is still a challenging field of research. In this work, the boron Lewis acid B[OTeF3(C6F5)2]3 was synthesized by reaction of the teflate derivative HOTeF3(C6F5)2 with BCl3 or BCl3·SMe2. This new compound presents a remarkably high thermal stability up to 300 °C, as well as one of the most sterically encumbered boron centres known in the literature. Theoretical and experimental methods revealed that B[OTeF3(C6F5)2]3 exhibits a comparable Lewis acidity to that of the well-known B(C6F5)3 and around 85% of the Lewis acidity of the related B(OTeF5)3. The affinity of B[OTeF3(C6F5)2]3 towards pyridine was accessed by Isothermal Titration Calorimetry (ITC) and compared to that of B(OTeF5)3 and B(C6F5)3. The ligand-transfer reactivity of this new boron compound towards different fluorides was demonstrated by the formation of an anionic Au(III) complex and a hypervalent iodine(III) species.PMID:38625061 | DOI:10.1002/chem.202401231

Source: Chemistry - April 16, 2024 Category: Chemistry Authors: Daniel Wegener Alberto P érez-Bitrián Niklas Limberg Anja Wiesner Kurt F Hoffmann Sebastian Hasenstab-Riedel Source Type: research