New Structural Features in Tetranuclear Iron Carbonyl Thiocarbonyls: Exotriangular Iron Atoms and Six-Electron-Donating Thiocarbonyl Groups Bridging Four Iron Atoms

作者：Zhang, Zhong .^*; Li, Qian-shu; King, R. Bruce; Schaefer, Henry F., III

来源：European Journal of Inorganic Chemistry, 2012, (7): 1104-1113.

DOI：10.1002/ejic.201100942

• Iron
• Metal thiocarbonyls
• Carbonyl ligands
• Cluster compounds
• Density functional calculations

DFT led to the discovery of two new structural motifs in tetranuclear iron carbonyl thiocarbonyls, Fe-4(CS)(4)(CO)(n) (n = 12, 11, 10, 9), which are not found in their homoleptic analogues, Fe-4(CO)(n+4). Thus the lowest energy Fe-4(CS)(4)(CO)(12) structures have a central Fe-3 triangle with an exotriangular iron atom joined to the Fe-3 triangle through a four-electron donor CS bridge. This contrasts with the structure of Os-4(CO)(16) and the predicted structure of Fe-4(CO)(16), which consist of an M-4 rhombus and two-electron donor carbonyl groups. An even more remarkable new structural motif for the Fe-4(CS)(4)(CO)(n) derivatives is the irregular Fe-4 "rhombus" (actually a trapezium) bridged by a six-electron donor eta(2)-mu(4)-CS group. This type of structure is found in the lowest energy structures of both Fe-4(CS)(4)(CO)(10) and Fe-4(CS)(4)(CO)(9) and makes Fe-4(CS)(4)(CO)(10) viable enough to be a promising synthetic objective. On the contrary, Fe-4(CS)(4)(CO)(11) is found to be thermochemically unfavorable both with respect to CO dissociation and disproportionation into Fe4CS)(4)(CO)(12) and Fe-4(CS)(4)(CO)(10).

• 出版日期2012-3
• 单位西北农林科技大学; 北京理工大学; 华南师范大学