:. Ms-(esi-+-)-m/z, ppm (s, 30H, Cp*), vol.11

B. , MS (ESI + ) m/z: calculated for C 20 H 33 B 2 S 7 Co, vol.2, p.2436

, MS (ESI + ) m/z: calculated for C 20 H 32 B 2 S 7, vol.3

. Ir-(dichloromethane, 22°C): ? = 3.69 (s, 3H, B-H t ), 1.51 ppm (s, 15H, Cp*); 11 B{ 1 H} NMR (160 MHz, 2436, 2373 (B-H t ). 4: 1 H NMR (500 MHz, vol.3

. Ir-(dichloromethane, Synthesis of Compounds 5, 6 and 7. The compounds 5, 6, and 7 were synthesized from the reaction of, p.2473

, mmol) and, 2018.

, 56) were afforded on elution with n-hexane/CH 2 Cl 2 (60:40 v/v) in thin layer chromatographic work-up, MS (ESI + ) m/z: calculated for C 10 H 19 B 3 Se 7 Co, vol.5

. Mhz, 22°C): ? = 114, CDCl, vol.3, issue.9

?. B-h-t-;-;-co and . Co, MS (ESI + ) m/z: calculated for C 20 H 34 B 3 Se 9 Co 3 [M] + , 1194.3519; found, 1194.3456. 1 H NMR (500 MHz, toluened 8 , 22°C): ? = 1.33 (s, 30H, Cp*), ?3.60 ppm (s, 1H, vol.6, p.2462

B. , 22°C): ? = 4.42 (s, 1H, B-H t ), 1.64 (s, 1H, B-H t ), 1.58 ppm (s, 30H, Cp*); 11 B{ 1 H} NMR (160 MHz, CDCl 3 , 22°C): ? = ?5.6, ?12.9 ppm; 13 C{ 1 H} NMR (125 MHz, MS (ESI + ) m/z: calculated for C 20 H 33 B 2 Co 2 Se 5, vol.7, p.2437

, IR (dichloromethane, cm ?1 ): 2453, 2368 (B-H t )

?. References-;-marchand, A. P. Paquette, L. A. Stowell, J. C. Dauben, W. G. Whalen et al., Silver ion catalyzed rearrangements of strained sigma bonds. Application to the homocubyl and 1,1'-bishomocubyl systems, J. Am. Chem. Soc, vol.89, issue.1, 1011.

P. E. Soc-;-eaton, T. W. Cole, P. E. Cubane-;-eaton, G. W. Griffin, A. P. Marchand et al., Cubanes: starting materials for the chemistry of the 1990s and the new century, Angew. Chem., Int. Ed. Engl, vol.86, pp.4574-4576, 1421.

P. E. Eaton, M. X. Zhang, R. L. Gilardi, N. Gelber, S. Iyer et al., Polynitrocubanes: advanced high-density, high-energy materials, Propellants, Explos., Pyrotech, vol.27, pp.1143-1148, 2000.

L. Mallick, H. K. Thakker, L. Sohan, S. Kumar, I. N. Namboothiri et al., Silver(I) ion catalyzed rearrangements at strained ? bonds. XXVIII. Valence isomerization of homocubanes. Reversible complex formation and kinetic substituent effects operating during silver(I)-induced bond reorganization, 11th Asia-Pacific Conference on Combustion, vol.97, pp.1101-1112, 1975.

L. A. Paquette, R. A. Boggs, W. B. Farnham, R. S. Beckley, L. A. Paquette et al., Silver(I) ion catalyzed rearrangements of strained ? bonds. XXX. Rhodium(I)-and Palladium(II)-promoted rearrangements of homocubanes. A comparison of kinetic reactivity and product distribution with substituent alteration, J. Am. Chem. Soc, vol.97, pp.1118-1124, 1975.

C. J. Mcneal, C. W. Liu, S. Song, Y. Huang, R. D. Macfarlane et al., Characterization of {M 8

?. }-4, M. Cu, I. , and A. I. , homocubane clusters by 252 Cfplasma desorption mass spectrometry, Int. J. Mass Spectrom, vol.222, pp.493-501, 2003.

R. D. Adams and S. Miao, Cyclopentadienylcobalt sulfide and selenide cluster compounds: synthesis and structural characterizations, Inorg. Chim. Acta, vol.358, pp.1401-1406, 2005.

H. Ogino, S. Inomata, and H. Tobita, Abiological Iron?Sulfur clusters, Chem. Rev, vol.98, 1998.

K. Geetharani, S. K. Bose, S. Sahoo, and S. Ghosh, A family of heterometallic cubane-type clusters with an exo-Fe(CO) 3 fragment anchored to the cubane, Angew. Chem., Int. Ed, vol.50, pp.3908-3911, 2011.

A. Thakur, S. Sao, V. Ramkumar, S. Ghosh, K. Yuvaraj et al., Homometallic Cubane Clusters: Participation of Three-Coordinated Hydrogen in 60-Valence Electron Cubane Core, Supraicosahedral polyhedra in metallaboranes: synthesis and structural characterization of 12-, 15-, and 16-vertex rhodaboranes, vol.51, pp.6705-6712, 2012.

S. Kar, K. Saha, S. Saha, K. Bakthavachalam, and S. Ghosh, Trimetallic cubane-type clusters: transition-metal variation as a probe of the roots of hypoelectronic metallaheteroboranes, Inorg. Chem, vol.57, pp.10896-10905, 2018.
URL : https://hal.archives-ouvertes.fr/hal-01862463

R. Borthakur, B. Mondal, P. Nandi, and S. Ghosh, Hypoelectronic isomeric diiridaboranes [(Cp*Ir) 2 B 6 H 6 ]: the "Rule-Breakers" (Cp* = ? 5 -C 5 Me 5 ), Chem. Commun, vol.52, pp.3199-3202, 2016.

A. De, Q. Zhang, B. Mondal, L. F. Cheung, S. Kar et al., Cp 2 M) 2 B 9 H 11 ] (M = Zr or Hf): early transition metal "guarded" heptaborane with strong covalent and electrostatic bonding, Chem. Sci, vol.9, 1976.

B. Mondal, R. Bag, S. Ghorai, K. Bakthavachalam, E. D. Jemmis et al., Synthesis, structure, bonding and reactivity of metal complexes comprising diborane(4) and diborene

W. M=mo, R. S. Anju, K. Saha, B. Mondal, V. Dorcet et al., Chemistry of diruthenium analogue of pentaborane(9) with heterocumulenes: toward novel trimetallic cubane-type clusters, Angew. Chem., Int. Ed, vol.57, issue.11, pp.10527-10535, 2014.

S. K. Barik, C. E. Rao, K. Yuvaraj, R. Jagan, S. Kahlal et al., Reductions with sulfurated borohydrides. III. Borohydrides incorporating selenium and tellurium, Eur. J. Inorg. Chem, vol.33, issue.12, pp.3695-3697, 1968.

R. Ramalakshmi, K. Saha, A. Paul, S. Ghosh, . Reactivity et al., Me] with chalcogenated borohydrides Li[BH 2 E 3 ] and B{ 1 H} and 1 H chemical shift values could not be unambiguously assigned until the pure spectroscopic data for 2 was realized, Acta Chem. Scand, vol.25, issue.14, pp.3781-3792, 1971.

J. L. Stark, B. Harms, I. Guzman-jimenez, K. H. Whitmire, R. Gautier et al.,

. E-=-bi, ). J. Br, T. S. Am-;-cameron, K. Jochem, A. Linden et al., Cp*Rh) 2 (?-E) 2 (? 3 -E) 4 B 2 H 2 ] is 72 [14(Cp*Rh) × 2 + 6(S, Se) × 6 + 4 (BH) × 2] and for ruthenium analogue [(Cp*Ru) 2 (?-E) 2 (? 3 -E) 4 B 2 H 2 ] (E = S or Se) it is 70. Note that the shortage of two electrons for the latter is supplemented by the formation of one Ru?Ru bond, Tetrahedron Lett, vol.121, issue.17, pp.4125-4127, 1970.

S. A. Godleski and P. V. Schleyer, Syntheses of (D 3 )-trishomocubane, J. Chem. Soc., Chem. Commun, pp.976-977, 1974.

G. J. Kent, S. A. Godleski, E. Osawa, P. V. Schleyer, G. Helmchen et al., Synthesis and Absolute Configuration of Enantiomerically Pure D 3 -Trishomocubanes, Angew. Chem., Int. Ed. Engl, vol.42, pp.116-117, 1977.

B. S. Krishnamoorthy, A. Thakur, K. K. Chakrahari, S. K. Bose, P. Hamon et al., Theoretical and experimental investigations on hypoelectronic heterodimetallaboranes of group 6 transition metals, Inorg. Chem, vol.51, pp.10375-10383, 2012.
URL : https://hal.archives-ouvertes.fr/hal-00753612

J. J. Schneider, U. Specht, R. Goddard, C. Kriigerl, M. A. Fox et al., 161?170. (22) (a) Wade, K. The structural significance of the number of skeletal bonding electron-pairs in carboranes, the higher boranes and borane anions, and various transition-metal carbonyl cluster compounds, Metal Atoms in the Synthesis of Metal Clusters, VIII. On the Reaction of Sterically Demanding Cyclopentadiene Ligands with Cobalt Atoms: Synthesis, Crystal Structure, vol.130, pp.93-144, 1976.
URL : https://hal.archives-ouvertes.fr/in2p3-00010773

J. R. Pipal and R. N. Grimes, Crystal structure of a tetracobalt tetraboron cluster, (? 5 -C 5 H 5 ) 4 Co 4 B 4 H 4 . Structural patterns in eightvertex polyhedra, Inorg. Chem, vol.18, pp.257-263, 1979.

T. Yoshino, H. Ikemoto, S. Matsunaga, M. Kanai, G. E. Ryschkewitsch et al., A Cationic High-Valent Cp*CoIII Complex for the Catalytic Generation of Nucleophilic Organometallic Species: Directed C?H Bond Activation, Angew. Chem., Int. Ed, vol.52, issue.25, 2013.