Theoretical and experimental comparison of the reactivity of the sulfanyl-closo-decaborate and sulfanyl-closo-dodecaborate anions and their mono-S-substituted derivatives

A synthesis of mono-S-substituted derivatives of sulfanyl- closo -decaborate anion was studied. Theoretical and experimental comparison of the reactivity of the sulfanyl- closo -decaborate and sulfanyl- closo -dodecaborate anions and their mono-S-substituted derivatives using DFT method was made. In this work, we have extended the method proposed by Gabel for the preparation of mono- and di-S,S-substituted derivatives of sulfanyl- closo -dodecaborate anion [B 12 H 11 SH] 2− to derivatives of the closo -decaborate anion. The method is based on the β-elimination of the propionitrile group of sulfonium derivatives [B n H n-1 S(R)CH 2 CH 2 CN] − in the presence of bases with the formation of the corresponding mono-S-substituted derivatives and acrylonitrile. We also calculated the Fukui functions for the nucleophilic attack of the S-atom in the [B 10 H 9 SH] 2− and [B 12 H 11 SH] 2− anions and their mono-S-substituted derivatives using the Hirshfeld approach. As a result, the calculated value of nucleophilicity in the [B 10 H 9 SH] 2− anion was found to be 5–10 times lower than in other compounds, which completely agrees with the experimental data.