Synthesis and crystal structure of the first “carbons apart” diamagnetic lutetiacarborane sandwich complex

The reaction of closo-exo-5,6-Na(THF)2-1-Na(THF)2-2,4-(SiMe3)2-2,4-C2B4H4 (1) and anhydrous LuCl3, in a molar ratio of 2:1, in dry benzene at 60 °C produced the first full-sandwiched lutetiacarborane complex, 2,2′,4,4′-(SiMe3)4-3,5′,6′-[(μ-H)3Na(THF)2]-1,1′-commo-Lu(η5-2,4-C2B4H4)2 (2), as an off-white crystalline solid in 88% yield.