Superhalogens as Building Blocks of Super Lewis Acids

Abstract

Lewis acids play an important role in synthetic chemistry. Using first‐principle calculations on some newly designed molecules containing boron and organic heterocyclic superhalogen ligands, we show that the acid strength depends on the charge of the central atom as well as on the ligands attached to it. In particular, the strength of the Lewis acid increases with increasing electron withdrawing power of the ligand. With this insight, we highlight the importance of superhalogen‐based ligands in the design of strong Lewis acids. Calculated fluoride ion affinity (FIA) values of B[C2BNO(CN)3]3 and B[C2BNS(CN)3]3 show that these are super Lewis acids.

SbCl4: An Exceptional Superhalogen as the Building Block of a Mixed Valence Supercrystal with Unconventional Ferroelectricity

“…The typical composition of a superhalogen is AX k +1 , where k is the valence of atom A and X is a halogen atom (e.g., BX 4 , AlX 4 , SiX 5 , and PX 6 ). Their anions are very stable, usually with low proton affinities, leading to superacids, , while their neutral components are not stable in the condensed phase. However, they can form stable supersalt solids when interacting with charge-compensating superalkalis [with low ionization potentials (≲3.9 eV)].…”

In Silico Investigation of the Mechanism of Disulfide Bond Dissociation by New Frustrated Lewis Pairs

“…In this study, a novel frustrated Lewis pair (FLP) system has been designed, consisting of the bulky Lewis base P­( t Bu) 3 and the super Lewis acid B­(C 2 NBSHF 2 ) 3 . The Lewis acid, B­(C 2 NBSHF 2 ) 3 , is electron-deficient due to the presence of the superhalogen ligand, which enhances its Lewis acidity compared to the conventionally used Lewis acid B­(C 6 F 5 ) 3 . , Very recently, these types of superhalogen ligands have been synthesized experimentally . As discussed earlier, we have used P­( t Bu) 3 ···B­(C 2 NBSHF 2 ) 3 for the activation of the disulfide bond.…”

Superhalogens inside fullerenes X@C2n (X = BO2, BeF3; 2n = 60, 70)

“…36 These superhalogens could function as robust electron acceptors and potential oxidizing agents, oxidizing various inert molecules including H 2 O, benzene, CO 2 and noble gas. 36,37 Moreover, they have been used as building blocks of supersalts, 38,39 superacids, 40,41 ionic liquids, 42 and other novel materials. 43 So is it possible to employ a neutral superhalogen to oxidize a fullerene cage and obtain endohedral superhalogen fullerenes with reverse charge transfer from the fullerene cage to the superhalogen?…”