Self-Assembly of Mercaptane−Metallacarborane Complexes by an Unconventional Cooperative Effect: A C−H···S−H···H−B Hydrogen/Dihydrogen Bond Interaction

Abstract

The existence of a dihydrogen bond (S−H···H−B) and its combination with a C−H···S hydrogen bond in an unusual cooperative effect are demonstrated from a combination of experimental and theoretical methods. This cooperative effect seems to be responsible for self-assembly of mercaptane−metallacarborane complexes such as closo-[3-Ru(η⁶-C₆H₆)-8-HS-1,2-C₂B₉H₁₀] (1) and closo-[3-Co(η⁵-C₅H₅)-8-HS-1,2-C₂B₉H₁₀] (3), which present identical supramolecular two-dimensional polymeric networks. The findings, besides documenting structurally the first S−H···(H−B)₂ dihydrogen bond and the unconventional cooperative ability of a boron-attached SH group, prove that substituted carboranes have the potential to serve as building blocks for assembling complex structures.