Tricarbahexaborane(7)

Metal atom synthesis of metallaboron clusters. 7. Synthesis and structural characterization of an open-cage metallathiaborane cluster having a triple-decker structure: 4,6-(.eta.-C5H5)2Co2-3,5-S2B2H2

“…Complexes with bridging arene ligands have also recently been characterized.34 Examples of structurally characterized triple-decker complexes along with the observed metal-metal and metal-ring distances are presented in The majority of triple-decker complexes contain 30 valence electrons35 (or in a cluster terminology 16 skeletal cage electrons) and therefore are in agreement with cluster electron-counting rules. However, complexes having 29 and 31-34 valence electrons (15,(17)(18)(19)(20) central cage electrons) are also known.28-34 The extra electrons in these complexes do not result in cage opening but instead result in a lengthening of the metal to ring distances.35 Thus, the 30-valence-electron clusters I-V all have metal-metal distances in the range of 3.1-3.27 Á, while the 32-electron compound VI has 3.337 Á, the 33-electron VII has 3.416 Á, and the 34-electron VIII has 3.576 Á metal-metal distances.…”

Synthesis and structural characterizations of ansa-vanadabis(tricarbadecaboranyl) sandwich complexes

“…Although the first tricarbaboranes [1], Me-C 3 B 3 H 6 and Me 2 -C 3 B 3 H 5 , and metallatricarbaborane complex [2], (Me-C 3 B 3 H 6 ) Mn(CO) 3 , were reported in seminal work by Grimes in 1966 and, it took over 20 more years to develop the efficient methods for the syntheses of the larger cage C 3 B 7 [3] and C 3 B 8 tricarbaboranes [4] that have now enabled the extensive and growing investigations of metallatricarbaborane chemistry [5]. Our work in this area has demonstrated that the 6-R-5,6,9-nido-C 3 B 7 H 9 e (R ¼ Me or Ph) [3,6] tricarbadecaboranyl anions can function as cyclopentadienyl analogs with the tricarbadecaboranyl sandwich complexes exhibiting properties that are complimentary to their metallocene cousins [7].…”

Quenched gas-phase reactions of tetraborane(10), B4H10, with substituted alkynes: new nido-dicarbapentaboranes and arachno-monocarbapentaboranes

“…4,5 Not long after these carbaboranes were first discovered, some 40 30 years ago, Grimes and co-workers reported a series of complex reactions of tetraborane (10), B 4 H 10 , with alkynes. [6][7][8][9][10][11][12][13][14][15] Many new carbaboranes were discovered from the gas-phase reactions of B 4 H 10 with ethyne HC≡CH. These reactions have also been explored more recently in Leeds.…”

“…These reactions have also been explored more recently in Leeds. [16][17][18][19] The reactions were of three 35 types, and the major carbaborane product in each case is shown below: 1) High-energy ('Flash') reaction 6,7,16,17 100 o C, 'Flash' 40 B 4 H 10 + HC≡CH → closo-2,4-C 2 B 5 H 7 (<1% yield) 2) Completed reaction 6,[8][9][10][11][12][13][14][15][16][17][18][19] 25-70 o C, 3 days B 4 H 10 + HC≡CH → nido-2,4-Me 2 -2,3-C 2 B 4 H 6 (7%) 45 …”