Tuning the Anomeric Effect in Sulfamide with Superacids

Leitz, Dominik; Bayer, Marie C.; Morgenstern, Yvonne; Zischka, Florian and Kornath, Andreas J. (2018): Tuning the Anomeric Effect in Sulfamide with Superacids. In: Chemistry-A European Journal, Vol. 24, No. 59: pp. 15825-15830

Abstract

This study shows that the anomeric effect (negative hyperconjugation) that arises in sulfamide, as a result of the relatively short S-N bonds, can be tuned by the utilization of superacidic media. Sulfamide was reacted in binary superacidic systems XF/MF5 (M = As, Sb;X = H, D) and HF/BF3. The colorless salts formed, [X2NSO2NX3](+)[MF6](-) and [H2NSO2NH3](+)[BF4](-) were characterized by low-temperature vibrational spectroscopy. In the case of [H2NSO2NH3](+)[BF4](-), a single crystal X-ray diffraction study was performed. The salt crystallizes in the monoclinic space group P2(1)/c with four formula units per unit cell. An exclusive N,N-diprotonation was observed in the superacidic system HF/SbF5 when using several equivalents of the Lewis acid. Low-temperature vibrational spectra as well as a single-crystal X-ray structure of [H3NSO2NH3](2+)2[SbF6](-)2 HF are reported. The salt crystallizes in the orthorhombic space group Pna2(1) with four formula units per unit cell. Upon mono- or diprotonation of sulfamide, remarkable structural changes of the sulfur-nitrogen bond lengths were observed. Herein, these changes are discussed together with quantum chemical calculations.

• Item Type: Journal article
• Faculties: Chemistry and Pharmacy > Department of Chemistry
• Subjects: 500 Science > 540 Chemistry
• ISSN: 0947-6539
• Language: English