Synthesis, structural characterization, and reactivity of rare-earth complexes derived from a new phosphorus-bridged versatile ligand, iPr2NP(C9H7)(C2B10H11)

New phosphorus-bridged ligands incorporating both indenyl and carboranyl moieties were prepared. Reaction of (Pr2NP)-Pr-i(C9H7)Cl (1) with 1 equiv of LiC2B10H10 gave, after treatment with 1 equiv of n-BuLi, the dilithium salt [(Pr2NP)-Pr-i(C9H6)(C2B10H10 )]Li-2(OEt2)(1.5) (2). 2 can be conveniently converted into its neutral counterpart (Pr2NP)-Pr-i(C9H7)(C2B10H10) (4) by treatment with excess dry Me3NHCl in CH2O2. Mixing 2 and 4 in a 1:1 molar ratio afforded quantitatively the monolithium salt [(Pr2NP)-Pr-i(C9H6)(C2B10H10)]Li(DME)(3) (3). Reaction of YbI2 with 1 equiv of 2 gave the organoytterbium(II) complex [eta(5):sigma-(Pr2NP)-Pr-i(C9H6)(C2B10H)10]Yb(DME)(2) (5). 5 reacted further with 1 equiv of 3 to afford the organoytterbium(III) complex [{eta(5):sigma-(Pr2NP)-Pr-i(C9H6)(C2B10H10)}(2)Yb][Li(THF)(3)(Et2O)] (6). In sharp contrast, treatment of SmI2 with 1 equiv of 2 generated the trivalent organosamarium complex [eta(5):sigma-(Pr2NP)-Pr-i(C9H6)(C2B10H10)(2)Sm] [Li(DME)(3)] (7). Reaction of LnCl(3) with 2 equiv of 2 gave the ionic complexes [{eta(5):sigma-(Pr2NP)-Pr-i(C9H6)(C2B10H10)}(2)Ln][Li(L-1)(n)L-2]] (L-1= L-2 = DME, n = 2, Ln = Sm (7), Nd (8), Er (9); L, = DME, L-2 = THF, n = 2, Ln = Y (10)). Reaction between equimolar amounts of LnCl(3) and 2 resulted in the isolation of the lanthanocene chlorides [{[eta(5):sigma-(Pr2NP)-Pr-i(C9H6)(C2B10H10)]LnCl}(2)(mu-Cl)(3)Li(DME)][Li(DME)(3)](2) (Ln = Er (11), Y (12)). The chloro groups in these complexes can be replaced by other moieties. For example, reaction of 12 with 2 equiv of (KCHPh)-Ph-2 afforded the unexpected compound {[eta(5):sigma-(Pr2NP)-Pr-i(C9H6)(C2B10H10)](2)Y}{(eta(6)-C6H5-CH3)(2)K} (13) and treatment of 12 with 2 equiv of NaBH4 produced the organoyttrium hydrides [{eta(5):sigma-(Pr2NP)-Pr-i(C9H6)(C2B10H10)}Y{(mu-H)(3)BH}(2)][Li(DME)(3)] (14). All complexes were fully characterized by various spectroscopic techniques and elemental analyses. The structures of some of the compounds were further confirmed by single-crystal X-ray analyses.