Synthesis, structures, DFT calculations, and Hirshfeld surface analysis of sulfonium derivatives of the closo-decaborate anion [B10X9-cyclo-S(CH2)4]- and [B10X9-cyclo-S(CH2CH2)2O]- (X = H, Cl, Br)

This work is devoted to the synthesis and modification of sulfur-containing derivatives of the closo-decaborate anion with cyclic substituents [2-B10H9-cyclo-S(CH2)(4)](-) (1) and [2-B10H9-cyclo-S(CH2CH2)(2)O](-) (2). Their perhalogenated analogs [2-B10Cl9-cyclo-S(CH2)(4)](-) (3), [2-B10Cl9-cyclo-S(CH2CH2)(2)O](-) (4), [2-B10Br9-cyclo-S(CH2)(4)](-) (5), and [2-B10Br9-cyclo-S(CH2CH2)(2)O](-) (6) were synthesized. The obtained compounds were investigated by B-11, H-1, and C-13 NMR spectroscopy and single crystal X-ray diffraction. The analysis of Hirshfeld surfaces and quantum-chemical calculations by the DFT method made it possible to establish the contribution of various intermolecular contacts to the crystal packing of compounds 1-6 and to study the effect of substitution of hydrogen atoms in the boron cage on the strength of the B-S bond. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

This study focuses on the synthesis and modification of sulfur-containing derivatives of the closo-decaborate anion, with the investigation of their perhalogenated analogs. Analysis using NMR spectroscopy, X-ray diffraction, Hirshfeld surfaces, and quantum-chemical calculations provided insights into the crystal packing of the compounds and the influence of substituting hydrogen atoms in the boron cage on the B-S bond strength.