The reactivities of the monosodium-complexed carborane precursors
nido-1-Na(C
4H
8O)-2-(R)-3-(SiMe
3)-2,3-C
2B
4H
5 (R = SiMe
3 (
1) or Me (
2)) with a number of lanthanide halides were investigated. Thereaction of LnCl
3 (or LnBr
3) with
1 in a 1:2 molar ratio in dry THF at 60
C produced the dimerizedhalf-sandwich lanthanacarborane complexes [2,3-(SiMe
3)
2-1-X-1-(THF)
m-1-Ln(
5-2,3-C
2B
4H
4)]
2·
n(THF)(
3, Ln = Y, X = Cl,
m = 2,
n = 1;
4, Ln = La, X = Br;
m = 1,
n = 0;
5, Ln = Ce, X = Br;
m = 1,
n = 0;
6, Ln = Pr, X = Br;
m = 2,
n = 1;
7, Ln = Nd; X = Cl,
m = 2,
n = 1;
8, Ln = Sm; X = Br,
m = 2,
n = 0;
9, Ln = Gd; X = Cl,
m = 2,
n = 1;
10, Ln = Tb, X = Cl,
m = 2,
n = 1;
11, Ln = Dy,X = Cl,
m = 2,
n = 1;
12, Ln = Ho, X = Cl,
m = 2,
n = 1;
13, Ln = Er, X = Cl,
m = 2,
n = 1;
14,Ln = Tm, X = Cl,
m = 2,
n = 1;
15, Ln = Yb, X = Cl,
m = 2,
n = 1;
16, Ln = Lu X = Cl,
m = 2,
n = 1) as crystalline solids in 70-92% isolated yields. In a similar manner, the reactions of
2 with LnCl
3at 65
C gave the corresponding complexes [2-Me-3-(SiMe
3)-1-Cl-1-(THF)
2-1-Ln(
5-2,3-C
2B
4H
4)]
2 (
17,Ln = Nd;
18, Ln = Dy; 1
9, Ln = Ho;
20, Ln = Er;
21, Ln = Yb) as crystalline solids in 72-80% yield.In both series of the reactions, 1 equiv of the particular neutral carborane was also produced. Thesubstitution of the chloride ions in complexes
17 and
20 by
2 gave the half-sandwich lanthanacarboraneclusters {2-Me-3-(SiMe
3)-1-[4,5-(
-H)-
nido-2-Me-3-(SiMe
3)-2,3-C
2B
4H
5]-1-Ln(
5-2,3-C
2B
4H
4)}
2·
n(THF)(
22, Ln = Nd,
n = 2;
24, Ln = Er,
n = 1) as crystalline solids in 82-87% yield. The reaction of
19 and
2 produced the trimer {2-Me-3-(SiMe
3)-1-[4,5-(
-H)-
nido-2-Me-3-(SiMe
3)-2,3-C
2B
4H
5]-1-Ho(
5-2,3-C
2B
4H
4)}
3·8(THF) (
23) in 57% yield. Complexes
22,
23, and
24 could directly be obtained in good yield(56-67%) from the reaction of
2 with the corresponding LnCl
3 at 65
C in molar ratios of 3:1 in dryTHF. Similarly, the mixed coordinated complex {2,3-(SiMe
3)
2-1-[4,5-(
-H)-(
nido-2-Me-3-(SiMe
3)-2,3-C
2B
4H
5)]-1-Gd(
5-2,3-C
2B
4H
4)}
2·3(THF) (
25) was obtained by reacting compound
9 with
2. To investigatethe importance of the halide in these reactions, (
5-Cp)LnCl
2 (Ln = Tb, Dy, Er) with
1 in a 1:2 molarratio produced lanthanacarborane complexes [1-(
5-C
5H
5)-2,3-(SiMe
3)
2-1-Ln(
5-2,3-C
2B
4H
4)]
2·
n(THF)(
26, Ln = Tb,
n = 2;
27, Ln = Dy,
n = 2;
28, Ln = Er,
n = 3) as crystalline solids in 77-82% isolatedyields. On the other hand, the reactions of (
5-Cp)
2ErCl and (
8-C
8H
8)GdCl with
1 in 1:1 molar ratiosdid not produce the half-sandwich lanthanacarboranes, but rather gave the
exo-polyhedral products {
exo-(
5-C
5H
5)
2Er[4,5-(
-H)-2,3-(SiMe
3)
2-2,3-C
2B
4H
4]}·(THF) (
29) and {
exo-(
8-C
8H
8)Gd[4,5-(
-H)-2,3-(SiMe
3)
2-2,3-C
2B
4H
4]·2(THF) (
30) as crystalline solids in 76% and 73% isolated yield, respectively. Allcompounds were characterized by IR spectroscopy and elemental analysis, whereas compounds
3,
7-
9,
10-
16,
18-
22,
29, and
30 were characterized by single-crystal X-ray diffraction studies. The diamagneticcompounds
3,
4, and
16 were additionally characterized by
1H,
13C, and
11B NMR spectroscopy.