Cluster Growth Reactions: Structures and Bonding of Metal-Rich Metallaheteroboranes Containing Heavier Chalcogen Elements

Chandan Nandi (1) , Arindam Roy (1) , Ketaki Kar (1) , Marie Cordier (2) , Sundargopal Ghosh (1)

1 IIT Madras - Indian Institute of Technology Madras
2 ISCR - Institut des Sciences Chimiques de Rennes

In an effort to synthesize cobalt-rich metallaheteroboranes from decaborane(14) analogues, we have studied the reaction of 10-vertex nido-[(Cp*Co)(2)B(6)H(6)E(2)] (Cp* = η(5)-C(5)Me(5), 1: E = Se and 2: E = Te) with [Co(2)(CO)(8)] under thermolytic conditions. All of these reactions yielded face-fused clusters, [(Cp*Co)(2)B(6)H(6)E(2){Co(CO)}(μ-CO){Co(3)(CO)(6)}] (3: E = Se and 4: E = Te). Further, when clusters 3 and 4 were treated with [Co(2)(CO)(8)], they underwent further cluster buildup reactions leading to the formation of 16-vertex doubly face-fused clusters [(Cp*Co)(2)B(6)H(6)E(2){Co(2)(CO)(2)}(μ-CO)(2){Co(4)(CO)(8)}] (5: E = Se and 6: E = Te). Cobaltaheteroboranes 3 and 4 comprise one icosahedron {Co(4)B(6)E(2)} and one square pyramidal {Co(3)B(2)} moiety, whereas 5 and 6 are made with one icosahedron {Co(4)B(6)E(2)} and two square pyramidal {Co(3)B(2)} cores. In an attempt to generate heterometallic metal-rich clusters, we have explored the reactivity of decaborane(14) analogue nido-[(Cp*Co)(2)B(7)TeH(9)] (7) with [Ru(3)(CO)(12)] at 80 °C, which afforded face-fused 13-vertex cluster [(Cp*Co)(2)B(7)H(7)Te{Ru(3)(CO)(8)}] (8). Cluster 8 is a rare example of a metal-rich metallaheteroborane in which one icosahedron {Co(2)Ru(2)B(7)Te} and a tetrahedron {Ru(2)B(2)} units are fused through a common {RuB(2)} triangular face. Further, the treatment of nido-[(Cp*Co)(2)B(6)S(2)H(4)(CH(2)S(2))] (9) with [Fe(2)(CO)(9)] afforded 11-vertex nido-[(Cp*Co)(2)B(6)S(2)H(4)(CH(2)S(2)){Fe(CO)(3)}] (10). The core structure of 10 is similar to that of [C(2)B(9)H(11)](2-) with a five-membered pentahapto coordinating face. All of the synthesized metal-rich metallaheteroboranes have been characterized by multinuclear nuclear magnetic resonance (NMR) spectroscopy, IR spectroscopy, ESI-MS, and structurally solved by single-crystal X-ray diffraction analysis. Furthermore, theoretical investigations gave insight into the bonding of such higher-nuclearity clusters containing heavier chalcogen atoms.

Mots clés: Carbon clusters; Cluster chemistry; Group 16 compounds; Mathematical methods; Metal clusters

Domaines: Chimie

Chandan Nandi, Arindam Roy, Ketaki Kar, Marie Cordier, Sundargopal Ghosh. Cluster Growth Reactions: Structures and Bonding of Metal-Rich Metallaheteroboranes Containing Heavier Chalcogen Elements. Inorganic Chemistry, 2022, 61 (42), pp.16750-16759. ⟨10.1021/acs.inorgchem.2c02601⟩. ⟨hal-03828845⟩