Cp*TaCl2B4H8: synthesis, crystal structure and spectroscopic characterization of an air-stable, electronically unsaturated, chiral tantalaborane

The Wade–Mingos rules in seven-vertex dimetallaborane chemistry: Hydrogen-rich Cp2M2B5H9 systems of the second and third row transition metals

“…Stable dimetallaboranes of nido-like stoichiometry resembling the original B n H nþ4 binary boranes that have been synthesized include the five-vertex derivatives Cp* 2 M 2 B 3 H 7 (M ¼ Co [12,13], Rh [14]), the six-vertex derivatives Cp* 2 M 2 B 4 H 8 (M ¼ Ir [15,16], Ru [17], and Re [18]), and the seven-vertex derivatives Cp* 2 M 2 B 5 H 9 (M ¼ Cr [19], Mo [19,20], W [21]), where Cp* ¼ h 5 -Me 5 C 5 . Hydrogen-richer seven-vertex systems Cp* 2 M 2 B 5 H 11 (M ¼ V [22], Ta [23,24] of arachno-like stoichiometry have also been synthesized.…”

Metallaboranes of the Early Transition Metals: Direct Synthesis and Characterization of [{(η5‐C5Me5)Ta}2BnHm] (n=4, m=10; n=5, m=11), [{(η5‐C5Me5)Ta}2B5H10(C6H4CH3)], and [{(η5‐C5Me5)TaCl}2B5H11]

“…Despite the availability of well-developed routes to metallaboranes of Group 6-9 metals, to our knowledge examples of characterized Group 5 metallaboranes are very rare. [21] Tantalaboranes [(Cp*Ta) 2 A C H T U N G T R E N N U N G (B 2 H 6 ) 2 ] [22] and [(Cp*Ta)Cl 2 B 4 H 8 ] [23] were synthe- (4) in modest yield. Compounds 1-3 are air-and moisture-sensitive but 4 is reasonably stable in air.…”

Metal fragment exchange from a molybdaborane to a tungstaborane

“…The compound has been characterised by 1 H, 11 B and 31 P NMR spectroscopy and elemental analysis. 1 The metallaborane ''MB 4 H 8 '' cage in (II) is known for a number of transition metals including tantalum [17], molybdenum [18], tungsten [19], iron [20] and cobalt [21]. The metallaborane cage in (II) is also completely isostructural with that of the known cluster nido-2-[W(PMe 3 ) 3 hydrogen on the basal atom furthest from the tungsten atom has been replaced by a {Mo(g-C 5 H 5 )(g 5 :g 1 -C 5 -H 4 )H 2 } fragment [22].…”