Bis(η5-isopropyltetramethylcyclo­pentadienyl)(tetrahydroborato-κ3H,H′,H′′)(tetrahydrofuran-O)-samarium(III): a lanthanidocene complex with a tridentate tetrahydroborato ligand

The lanthanidocene complex [Sm(BH4)(C12H19)2(C4H8O)], (I), shows a distorted tetrahedral arrangement around the central SmIII atom. It consists of two η5-isopropyltetramethylcyclopentadienyl ligands, one tetrahydroborato (BH4−) ligand bridging via H atoms to the lanthanide atom and one coordinating tetrahydrofuran (thf) molecule. The BH4− unit of (I) coordinates as a tridentate ligand with three bridging H atoms and one terminal H atom [Sm—B—H4 176 (2)°]. The η5-isopropyl­tetra­methylcyclopentadienyl ligands of this bent-sandwich complex [Cp1—Sm—Cp2 133.53 (1)° where Cp denotes the centroid of the cyclopentadienyl ring] adopt staggered conformations.