Bonding modes of stanna-closo-dodecaborate: η¹(Sn) to η³(BH) rearrangement reactions in zwitterionic stanna-closo-dodecaborate ruthenium complexes

Abstract

Reaction of the stanna-closo-dodecaborate salt [Bu3MeN]2[SnB11H11] with the dimeric ruthenium complex [Ru2(mu-Cl)3(triphos)2]Cl (triphos = {MeC(CH2PPh2)3}) in refluxing acetonitrile yields the zwitterionic compound [Ru(SnB11H11)(MeCN)2(triphos)] (4) which has been characterized by single-crystal X-ray diffraction analysis and solid-state NMR spectroscopy. Refluxing the zwitterion in acetone leads to an eta1(Sn) to eta3(BH) rearrangement with formation of [Ru(SnB1)H11)(triphos)] (5) whose structure has been confirmed by X-ray diffraction and multinuclear NMR spectroscopy in solution and in the solid state. Furthermore, two isomeric zwitterions fac- and mer-[Ru(SnB11H11)(dppb)(MeCN)3] (6a, 6b) and their rearrangement reactions as well as their NMR properties are described.

Heteroborane analogs of silicon clusters: Experimental and theoretical studies on Bi2Si5 and Bi2Si5−

“…By equating the -lone pair of divalent silicon to a B-H bond, it was shown that the frontier orbitals of both units are similar. 18,19 Based on the same concept, neutral analogs for closoboranes, B n H n 2− , can also be constructed by replacing two BH − ͑five valence electrons each͒ units with other isovalent units. Meanwhile, Zdetsis 15 systematically studied the one-to-one correspondence between Si n 2− and the corresponding closo-boranes, B n H n 2− , by comparing their structural and electronic features.…”

Octahedral Coordination Compounds of the Ni, Pd, Pt Triad

“…[2] In its reaction with platinum electrophiles, we found complexes which are active catalysts in hydroformylation reactions; with the coinage metals, cluster formation is the dominant reaction; and with ruthenium complex fragments, ambident coordination modes together with dynamic behavior of the heteroborate were characterized. [3][4][5][6][7][8][9][10] To synthesize a diazabutadiene nickel complex with stanna-closo-dodecaborate as ligand, we treated the nickel halide [Ni(dpp-bian)Br 2 ] with three equivalents [SnB 11 H 11 ] 2À (Scheme 1). [11] The octahedral nickel complex 1 was isolated from this reaction mixture as purple crystals and was characterized by elemental analysis, mass spectrometry, X-ray crystal structure analysis (Figure 1), heteronuclear NMR spectroscopy (Figures 3 and 4) and 119 Sn Mössbauer spectroscopy ( Figure 6).The octaanionic complex [Ni(SnB 11 H 11 ) 6 ] 8À with nickel in the formal oxidation state IV is the product of an oxidation reaction, raising the question of the corresponding reduction product.…”

Dinuclear copper complexes: coordination of Group 14 heteroborates

“…These complexes show a reversible coordination mode rearrangement between η 3 (BH) and η 1 (Sn) coordination. 30,[83][84][85] In the 1 H NMR spectrum of complex 3 for the coordinated and uncoordinated Me 2 N-groups we detect at room temperature one signal at 2.48 ppm which is indicative for an exchange procedure and should be compared with the signal for the uncoordinated ligand at 2.76 ppm. At −80 °C in the 1 H NMR spectrum three signals for the coordinated and uncoordinated Me 2 N-groups were observed.…”