Novel Lanthanocene Analogues of “Carbons Apart” Erba- and Dysprosacarboranes: Synthetic and Structural Investigation

The reaction of closo-exo-5,6-Na(THF)2-1-Na(THF)2-2,4-(SiMe3)2-2,4-C2B4H4 (1) and anhydrous LnCl3, in a molar ratio of 3:1, in dry benzene at 60 °C produced novel lanthanocene analogues of metallacarborane complexes of the formula [Na3][1,1‘-[5,6-(μ-H)2-nido-2,4-(SiMe3)2-2,4-C2B4H4]-2,2‘,4,4‘-(SiMe3)4-1,1‘-commo-Ln(2,4-C2B4H4)2] (Ln = Er (2), Dy (3)) as yellow crystalline solids in 82% and 78% yields, respectively, thus establishing a new structural pattern for lanthanacarboranes.