Vertex-Fused Metallaborane Clusters: Synthesis, Characterization and Electronic Structure of [(η⁵-C₅Me₅Mo)₃MoB₉H₁₈]

Abstract

The reaction of the [(eta(5)-C(5)Me(5))MoCl(4)] complex with [LiBH(4).THF] in toluene at -70 degrees C, followed by pyrolysis at 110 degrees C, afforded dark brown [(eta(5)-C(5)Me(5)Mo)(3)MoB(9)H(18)], 2, in parallel with the known [(eta(5)-C(5)Me(5)Mo)(2)B(5)H(9)], 1. Compound 2 has been characterized in solution by (1)H, (11)B, and (13)C NMR spectroscopy and elemental analysis, and the structural types were unequivocally established by crystallographic studies. The title compound represents a novel class of vertex-fused clusters in which a Mo atom has been fused in a perpendicular fashion between two molybdaborane clusters. Electronic structure calculations employing density functional theory yield geometries in agreement with the structure determinations, and on grounds of density functional theory calculations, we have analyzed the bonding patterns in the structure.

A close-packed boron-rich 11-vertex molybdaborane with novel geometry

“…Å in 2 and 0.19 Å in 3 clusters. The cross-cluster MoeMo distance in 2 and 3 is longer than the usual MoeMo single bond distance observed in the molybdaboranes [(Cp * Mo) 2 B 5 H 9 ] or [(Cp * Mo) 2 B 4 H 6 SFe(CO) 3 ] [12,13] but comparable with the distances observed in [(Cp * Mo) 3 MoB 9 H 18 ][14].The spectroscopic data of 1e3 are fully consistent with the solid state structures, shown in the Figs. 1 and 2 andFig.…”

Chemistry of ruthenium σ-borane complex, [Cp∗RuCO(μ-H)BH2L] (Cp∗= η5-C5Me5; L = C7H4NS2) with terminal and internal alkynes: Structural characterization of vinyl hydroborate and vinyl complexes of ruthenium

“…Transition-metal complexes of boron, [1][2][3] have attracted considerable interest over the last few decades. A wide variety of coordination modes of these complexes have been structurally characterized and theoretically examined [4] that led to the progress of new subclasses such as sigma, agostic, boryl, borylene, boratrane and more [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Hill, Parkin, Bourissou, Sabo-Etienne, Braunschweig, Weller, Aldridge, and others have synthesized a number of such novel complexes by substitution and addition reactions of boron containing ligands at an electronically unsaturated metal centre [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34].…”

Synthesis of Trithia-Borinane Complexes Stabilized in Diruthenium Core: [(Cp*Ru)2(η1-S)(η1-CS){(CH2)2S3BR}] (R = H or SMe)

“…The mutually synergistic interactions between metals and organic ligands often generate compounds of fundamental and practical importance [1][2][3][4][5][6]. The structure and reactivity of metallaboranes, which features compounds with an M-B bond, is greatly influenced by transition metals as well as organic ligands [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25]. Previous studies have been carried out to understand the ways in which metal and borane fragments can interact to generate novel geometries [1][2][3][4][16][17][18][19][20][21][22][23][24][25].…”