Organometallic Compounds of the Lanthanides. 183
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Experimental Section
[Li(tmeda)2][Nd(CHPhSiMe2 Bu)3Cl] (6b)
6b was prepared in analogy to 5a from NdCl3 (0.30 g, 1.20 mmol)
and 2 (1.05 g, 3.20 mmol). Analogous workup of the orange-green
reaction mixture leads after standing of the concentrated ether ex-
tract at Ϫ36 °C for some weeks to the separation of small bunches
of needle like crystals of 6b. Slow cooling of a saturated ether
solution of these crystals to 0 °C produces light-green single
crystals of 6b. Yield: 0.76 g (61 %). Mp: 150Ϫ155 °C (dec).
C51H95ClLiN4NdSi3 (1035.23 g/mol): Nd 13.76 (calcd 13.93) %.
General Remarks: All manipulations involving air sensitive com-
pounds were carried out in dry, oxygen-free solvents and under an
inert atmosphere of nitrogen using standard Schlenk techniques.
The solvents were dried by distillation from sodium-benzophenone.
Melting points were measured in sealed capillaries with a Büchi
510 melting point determination apparatus and are uncorrected.
1H and 13C NMR spectra were recorded on a Bruker ARX 400
(1H, 400.13 MHz; 13C, 100.64 MHz) spectrometer at ambient tem-
perature. Chemical shifts are reported in ppm and referenced to the
1H and 13C residues of the deuterated solvents. Ln analyses were
performed by complexometric titration with EDTA as indicator.
Commercially available reagents were of reagent-grade quality
and were used as received. [Li(tmeda)][CHPhSiMe3] (1) [12],
[Li(tmeda)2][Sm(CHPhSiMe3)3Cl] (7a)
7a was prepared in analogy to 5a from SmCl3 (1.06 g, 2.65 mmol)
and 1 (2.20 g, 7.68 mmol). Analogous workup of the dark violet
reaction mixture resulted in the formation of small, dark violet
crystals of 7a. Slow cooling of a saturated ethereal solution of these
crystals to Ϫ36 °C yielded rectangular single crystals. Yield: 0.75 g
(31 %). Mp: 139Ϫ140 °C (dec). C42H77ClLiN4Si3Sm (915.11 g/
mol): Sm 16.82 (calcd 16.43) %.
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[Li(tmeda)][CHPhSiMe2 Bu] (2) [13], [Li(tmeda)][CHPhSiMe2Ph]
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(3) [13], [Li(tmeda)][CH(C6H3Me2-3,5)SiMe2 Bu] (4) [13], and the
water-free trichlorides of Pr, Nd, Sm, Er and Lu [36] were prepared
according to published procedures.
1H NMR (400 MHz, pyridine-d5): δ ϭ Ϫ0.2 to Ϫ1.6 (m, 27H, SiMe3),
1.8Ϫ2.1 (m, 3H, CH), 2.17 (s, 24H, NCH3), 2.39 (s, 8H, NCH2), 7.0Ϫ7.5
(m, 15H, Ph).
[Li(tmeda)2][Pr(CHPhSiMe3)3Cl] (5a)
A solution of PrCl3 (0.4 g, 1.62 mmol) in THF (30 mL) was treated
drop wise with a solution of 1 (1.31 g, 4.57 mmol) in THF (25 mL)
at room temperature. The yellow-green mixture was stirred for 12 h.
Then the solvent was evaporated in vacuum and the oily residue
was extracted with diethyl ether. The ethereal extract was filtered
off from precipitated LiCl, then the clear solution was concentrated
to 10 mL and subsequently cooled to Ϫ36 °C. In the course of 12 h
light green crystals of 5a precipitated. Yield: 0.74 g (54 %). Mp:
116Ϫ118 °C (dec). C42H77ClLiN4PrSi3 (905.66 g/mol): Pr 15.67
(calcd 15.56) %.
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[Li(tmeda)2][Sm(CHPhSiMe2 Bu)3Cl] (7b)
7b was prepared in analogy to 5a from SmCl3(THF)2 (0.37 g,
0.93 mmol) and 2 (0.89 g, 2.71 mmol). Analogous workup of the
violet reaction mixture and cooling for 2 d afforded small bunches
of dark violet, needle like crystals of 7b. Slow cooling of a saturated
solution of these crystals in toluene first to 0 °C and then to
Ϫ36 °C led to the formation of almost black crystals of the mono
toluene adduct of 7b. Yield: 0.50 g (53 %). Mp: 142Ϫ144 °C (dec).
C51H95ClLiN4Si3Sm (1041.35 g/mol): Sm 14.98 (calcd 14.44) %.
1H NMR (400 MHz, pyridine-d5): δ ϭ Ϫ0.09 (s, 9H, SiCH3), 0.14 (s, 9H,
SiCH3), 0.35 (s, 27H, Bu), 2.11 (s, 3H, CH), 2.17 (s, 24H, NCH3), 2.38 (s,
8H, NCH2), 6.92Ϫ7.44 (m, 15H, Ph).
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[Li(tmeda)2][Pr(CHPhSiMe2 Bu)3Cl] (5b)
5b was prepared in analogy to 5a from PrCl3 (0.35 g, 1.42 mmol)
and 2 (1.49 g, 4.54 mmol). Analogous workup of the dark green to
brown colored reaction mixture afforded after cooling for some
days dark green crystals of 5b. Yield: 1.31 g (89 %). Mp:
108Ϫ110 °C (dec). C51H95ClLiN4PrSi3 (1031.90 g/mol): Pr 14.09
(calcd 13.66) %.
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[Li(tmeda)2][Er{CH(C6H3Me2-3,5)SiMe2 Bu}3Cl] (8d)
8d was prepared in analogy to 5a from ErCl3 (0.41 g, 1.5 mmol)
and 4 (1.56 g, 4.37 mmol). Analogous workup of the orange-pink
reaction mixture resulted in the formation of light pink crystals of
8d. Slow cooling of a saturated ethereal solution of this crystals to
Ϫ36 °C afforded square pink single crystals of 8d(Et2O)2. Drying
of the adduct in vacuum gave ether free 8d. Yield: 0.68 g (40 %).
Mp: 152Ϫ153 °C (dec). C57H107ClErLiN4Si3 (1142.41 g/mol): Er
14.33 (calcd 14.64) %.
[Li(tmeda)2][Pr(CHPhSiMe2Ph)3Cl] (5c)
5c was prepared in analogy to 5a from PrCl3 (0.35 g, 1.42 mmol)
and 3 (1.48 g, 4.25 mmol). Analogous workup of the dark brown-
green reaction mixture and cooling for some days resulted in the
precipitation of green, amorphous 5c. Yield: 0.74 g (48 %). Mp:
110Ϫ113 °C (dec). C57H83ClLiN4PrSi3 (1091.87 g/mol): Pr 13.19
(calcd 12.91) %.
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[Li(tmeda)2][Lu{CH(C6H3Me2-3,5)SiMe2 Bu)3Cl]
(9d)
9d was prepared in analogy to 5a from LuCl3(THF)3 (0.71 g,
1.41 mmol) and 4 (1.56 g, 4.35 mmol). Analogous workup of the
light yellow reaction mixture resulted in the formation of colorless
microcrystalline 9d. Slow cooling of a saturated ethereal solution of
these crystals to Ϫ36 °C produced big square crystals of 9d(Et2O).
Drying of the adduct in vacuum gave ether free 9d. Yield: 0.86 g
(53 %). Mp: 120Ϫ122 °C. C57H107ClLiLuN4Si3 (1150.12 g/mol)):
Lu 15.31 (calcd 15.21) %.
[Li(tmeda)2][Nd(CHPhSiMe3)3Cl] (6a)
6a was prepared in analogy to 5a from NdCl3 (0.41 g, 1.64 mmol)
and 1 (1.40 g, 4.89 mmol). Analogous workup of the orange-green
reaction mixture resulted in the formation of small bunches of light
green needle like crystals of 6a. Yield: 0.47 g (31 %). Mp:
120Ϫ122 °C (dec). C42H77ClLiN4NdSi3 (908.99 g/mol): Nd 15.96
(calcd 15.87) %.
1H NMR (400 MHz, pyridine-d5): δ ϭ 0.08 (s, 9H, SiCH3), 0.28 (s, 9H,
SiCH3), 0.60 (s, 27H, C(CH3)3), 2.07 (s, 8H, CH3C6H3), 2.15 (s, 10H,
Z. Anorg. Allg. Chem. 2008, 2199Ϫ2208
© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
2205
Schumann, Herbert
