Diruthenium analogues of Hexaborane(12) and Pentaborane(9): Synthesis and structural characterization of [(1,2-Cp*Ru)2B2H6S2] and [(2,3-Cp*Ru)2B3H6(μ-η1-EPh)], (E = S, Se and Te) (Cp* = η5-C5Me5)

•Syntheses of novel group 8 metallaheterobaranes have been described.•Metallaheterobarane analogue of [B6H12] has been synthesized.•Results highlight the possibility for a new class of metallaheteroboranes.

In an objective to synthesize metallaheteroboranes containing heavier chalcogen atoms, we performed the reaction of dimetallaborane analogues of pentaborane(9) with various chalcogen sources. As a result, the thermolysis of nido-[1,2-(Cp*RuH)2B3H7], 1 (Cp* = η5-C5Me5) with mixture of S and Se powder was carried out, that led to the isolation of half sandwich dimetallaheteroborane arachno-[(1,2-Cp*Ru)2B2H6S2], 2. On the other hand, the reaction of nido-1 with diorganyldichalcogenide ligands, [Ph2E2] afforded chalcogen bridged half sandwich complexes [(2,3-Cp*Ru)2B3H6(μ-η1-EPh)], 4a-c (4a: E = S; 4b: E = Se and 4c: E = Te). Compound 2 can be derived from a closo-snub disphenoid by removing a 5-connect vertex followed by the removal of a 3-connect vertex. Compound 4a–c can be described as nido-square pyramidal structures, isoelectronic and isostructural with nido-1. All the compounds have been characterized by mass spectrometry, 1H, 11B and 13C spectroscopy. Further, the geometry of compounds 2, 3, 4b and 4c were unequivocally established by crystallographic analysis.

Graphical abstractDimetallaborane analogues of hexaborane(12), [(1,2-Cp*Ru)2B2H6S2] and pentaborane(9), [(2,3-Cp*Ru)2B3H6(μ-η1-EPh)] (E = S, Se ad Te) containing heavier chalcogen elements have been structurally characterized.Figure optionsDownload full-size imageDownload as PowerPoint slide