[{[(η7-C2B10H12)(η6-C2B10H12)U][K2(thf)5]}2]: A Metallacarborane Containing the Novelη7-C2B10H124− Ligand

Abstract

The tetranion ligand η -C B H has been observed for the first time in 1, which was obtained from the reaction of o-C B H with excess K metal followed by treatment with UCl . As shown in the picture (without K cations and coordinated THF molecules), 1 is a centrosymmetric dimer with a bent sandwich structure.

A New Class of Metallacarboranes: Synthesis and Molecular Structure of the First Example of an Organolanthanide Compound Bearing an η7-Carboranyl Ligand

“…The chemistry of metallacarboranes has witnessed an explosive growth since the discovery of the first metallacarborane in 1965. , However, the highest hapticity of carboranyl ligands in all of known metallacarboranes described in the literature is 6; that is, the largest bonding face that a carboranyl ligand can offer is a hexagonal face . We have very recently reported the unprecedented uranium compound [{( η 7 -C 2 B 10 H 12 )( η 6 -C 2 B 10 H 12 )U}{K 2 (THF) 5 }] 2 , in which the U atom is η 7 -bound to one of the C 2 B 10 H 12 ligands . We report here a new class of metallacarboranes derived from the versatile ligand Me 2 C(C 5 H 5 )(C 2 B 10 H 11 ).…”

New class of metallacarboranes incorporating the η7-carboranyl ligand

“…1, it is a centrosymmetric dimer with a bent sandwich structural motif. Each U atom is η 6 -bound to nido-C 2 B 10 H 12 2-, η 7 -bound to arachno-C 2 B 10 H 12 4-, and coordinated to two B-H bonds from the C 2 B 5 bonding face of the neighboring arachno-C 2 B 10 H 12 4-ligand, resulting in a highly distorted-tetrahedral geometry at U atom [3]. 2 represents not only the first metallacarborane containing a novel η 7 -C 2 B 10 H 12 4-ligand, but also the first organoactinide compound bearing a η 6 -C 2 B 10 H 12 2-ligand.…”

“…The asymmetrical units are then linked to each other via B-H-Er bonds to form an infinitive polymeric chain. An X-ray analysis reveals that 5 is a centrosymmetric tetranuclear lanthanacarborane cluster with two {[η 5 :η 7 -Me 2 C(C 5 H 4 )(C 2 B 10 H 11 )]Er 2 (µ-Cl)(THF) 3 } units that are connected by two sets of three B-H-Er 2e-3c bonds (Fig. 4).…”

3 Boron

“…A uranium carborane containing the novel [Z 7 -C 2 B 10 H 12 ] 4À ligand has been reported. 108 The ¢rst examples of ``double-cluster'' metallatricarbollides have been synthesised, [9,9-(Bu t HN) 2 -commo-2,2 H -M-closo-1,7,9-(C 3 B 8 H 10 )-1 H ,7 H ,9 H -(C 3 B 9 H 10 )] (M Fe, Ru). These neutral complexes are the metallacarborane analogues of ferrocene and ruthenocene.…”