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Strong Lewis and Bronsted Acidic Sites in the Borosulfate Mg₃ [H₂ O→B(SO₄ )₃ ]₂.

ABSTRACT: Borosulfates provide fascinating structures and properties that go beyond a pure analogy to silicates. Mg₃ [H₂ O→B(SO₄ )₃ ]₂ is the first borosulfate featuring a boron atom solely coordinated by three tetrahedra. Thus, the free Lewis acidic site forms a Lewis acid-base adduct with a water molecule. This is unprecedented for borosulfate chemistry and even for borates. Quantum chemical calculations on water exchange reactions with BF₃ and B(C₆ F₅ )₃ revealed a higher Lewis acidity for the borosulfate anion. Moreover, proton exchange reactions showed a higher Brønsted acidity than comparable silicates or phosphates. Additionally, Mg₃ [H₂ O→B(SO₄ )₃ ]₂ was characterised by X-ray diffraction, infrared spectroscopy, thermogravimetric analysis, and density functional theory (DFT) calculations.

SUBMITTER: Netzsch P

PROVIDER: S-EPMC8251581 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature

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Strong Lewis and Brønsted Acidic Sites in the Borosulfate Mg3 [H2 O→B(SO4 )3 ]2.

Netzsch Philip P Stroh Regina R Pielnhofer Florian F Krossing Ingo I Höppe Henning A HA

Angewandte Chemie (International ed. in English) 20210330 19

Borosulfates provide fascinating structures and properties that go beyond a pure analogy to silicates. Mg3 [H2 O→B(SO4 )3 ]2 is the first borosulfate featuring a boron atom solely coordinated by three tetrahedra. Thus, the free Lewis acidic site forms a Lewis acid-base adduct with a water molecule. This is unprecedented for borosulfate chemistry and even for borates. Quantum chemical calculations on water exchange reactions with BF3</su ...[more]

PMID: 33751735

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