Use of Neodymium Diiodide in the Synthesis of Organosilicon, -Germanium and -Tin Compounds
2 Experimental Section
2.5 Reaction of 1 with Me2SiCl2
To a solution of 1 (6.46 g, 16.22 mmol) in 15 ml THF a solution
of 1.05 g (8.11 mmol) of Me2SiCl2 in 5 ml THF was added at
Ϫ60 °C. When the reaction mixture was warmed to room tempera-
ture, a vigorous reaction and change of reaction color to brown
was observed. During 16 h the color of the mixture turned light
blue, and a gray precipitate deposited. Solvent and volatile prod-
ucts were separated by condensation in vacuum. GLC analysis of
the volatiles revealed the presence of Me2Si(OBun)2 and
Me2Si(OBun)Cl. The precipitate was extracted with hexane in
which Me2Si(OBun)2 and Me2Si(OBun)Cl were found by GLC
along with minor amounts of several unidentified less volatile com-
pounds. An IR spectrum of the mixture revealed the bands of
Me2Si (1258, 840 cmϪ1) and Si-OBu (1096 cmϪ1) groups. The
UV/vis spectrum contained an absorption at 215 nm. The remain-
ing precipitate was extracted with benzene in which the same set
of products was identified by GLC. The total yield of
Me2Si(OBun)2 and Me2Si(OBun)Cl was 0.89 g (54 %) and 22 mg
(2 %) respectively. Drying of the precipitate under vacuum at 70 °C
gave 9.8 g (98 %) of NdI2Cl(THF)2.5. Anal. Found (Calc.): Nd,
23.51 (23.52) %.
2.1 Materials and methods
All procedures were performed under vacuum using standard
Schlenk-tube techniques. THF, DME, toluene, and benzene were
rigorously dried by refluxing over sodium followed by treatment
with a small amount of 1. The resulting solution was kept for
10 min, and then the solvent was condensed into a reaction vessel.
Neodymium diiodide (1) was prepared according to published pro-
cedures [5]. Me3SiCl, Me2SiCl2, Me3SiSiMe3, Me3SiI and Me3SnCl
were purchased from Aldrich company. Me3SiPrn [6], Me3SiOBun
[1g], Me2Si(OBu)2, Me2Si(OBu)Cl [7], Me3GeBr [8], Me3GeH [9],
Et3GeBr, Et3GeH [10], Me3GeGeMe3, Me3SnSnMe3 [11],
Et3GeGeEt3 [12], and Me3SnH [13] were prepared according to
published procedures. IR spectra were recorded on a Specord
M-75 spectrometer. The samples were prepared as Nujol mulls and
as films between KBr plates. Volatile organic products were ana-
lyzed on a Tsvet-800 gas chromatograph equipped with a thermal
conductivity detector and a stainless-steel column (3 m long and
3 mm O.D.). In these analyses 5 % SE-30 on Chromaton N-AW
(granules 0.2-0.25 mm) was used as an absorbent. Quantitative
analyses of the reaction mixtures were performed by the method
of an absolute calibration.
2.6 Reaction of 1 with Me3GeBr
A solution of Me3GeBr (1.034 g, 5.23 mmol) in 5 ml THF was ad-
ded under stirring to a dark violet solution of 2.104 g (5.28 mmol)
of 1 in 5 ml THF at Ϫ60 °C. The color of the mixture immediately
turned pale brown, and a gray precipitate of neodymium trihalide
was formed. The mixture was allowed to warm to room tempera-
ture and stirred for 30 min. The precipitate was separated by fil-
tration, washed with THF and dried. The yield of NdI2Br(THF)3
was 3.619 g (99 %). Anal. Found (Calc.): Nd, 20.87 (20.78) %. Me3-
GeH (21 mg, 3 %), Me3GeI (87 mg, 7 %), Me3GeGeMe3 (0.273 g,
44 %) were identified in the solution by means of GLC analysis.
Under the same reaction conditions using 0.636 g (2.66 mmol) of
Et3GeBr and 2.114 g (5.31 mmol) of 1, 55 mg (13 %) of Et3GeH
and 0.24 g (57 %) of Et3GeGeEt3 were obtained.
2.2 Reaction of 1 with Me3SiCl in DME
A solution of Me3SiCl (0.671 g, 6.18 mmol) in 3 ml DME was ad-
ded with stirring to a dark violet solution of 1 (2.459 g, 6.18 mmol)
in 4 ml DME at Ϫ60 °C. The mixture was allowed to warm to
room temperature and stirred for 16 h. The color of the mixture
turned brown. A formed gray precipitate (3.62 g) was separated by
filtration through a glass filter and the resulting solution was exam-
ined by GC. The analysis revealed the presence of Me3SiH (27 mg,
6 %), (Me3Si)2O (85 mg, 19 %) and hexamethyldisilane (19 mg,
4 %). In addition, 0.323 g (48 %) of the starting chlorosilane
Me3SiCl was recovered from the solution along with a small
amount of unidentified products.
2.3 Reaction of 1 with Et3SiBr (3) in THF
2.7 Reaction of 1 with Me3SnCl
To a solution of 1 (1.82 g, 4.57 mmol) in 10 ml THF a solution of
0.89 g (4.57 mmol) of Et3SiBr in 5 ml THF was added at Ϫ60 °C.
The mixture was warmed to room temperature and stirred for 16 h.
The initial violet color of the solution gradually changed to pale
blue, and a precipitate of NdI2Br(THF)3 (3.0 g, 95 %) was formed.
Solvent and volatile products were removed by condensation in
vacuum and analyzed by GC. 0.28 g (34 %) of Et3SiOBun and
85 mg (17 %) of Et3SiSiEt3 were found.
To a solution of 1 (2.084 g, 5.24 mmol) in 5 ml THF was added a
solution of Me3SnCl (1.043 g, 5.24 mmol) in 4 ml THF at Ϫ60 °C.
The mixture was allowed to warm to room temperature and stirred
for 30 min. Slight warming of the mixture was observed. The initial
dark violet solution acquired a brown color, and a grayish precipi-
tate was formed. The precipitate was filtered off and dried. Dissol-
ution of the precipitate in water left a gray amorphous precipitate,
which was identified as tin metal (0.46 g, 74 %). In the THF solu-
tion 57 mg (7 %) of Me3SnH and 97 mg (11 %) of Me3SnSnMe3
were found.
2.4 Reaction of 1 with Me3SiCl and PrnCl
To a solution of 1 (4.788 g, 12.03 mmol) in 10 ml THF was added
a solution of Me3SiCl (0.653 g, 6.01 mmol) and PrnCl (0.472 g,
6.01 mmol) in 5 ml THF at Ϫ60 °C. The mixture was allowed to
warm to room temperature and stirred for 30 min. Slight warming
of the mixture was observed. The initial dark violet solution gradu-
ally acquired a brown color, and a precipitate of NdI2Cl(THF)4
(7.53 g, 87 %) was formed. After separation of the precipitate by
filtration the solution was analyzed by GC. Me3SiPrn (68 mg,
10 %), Me3SiOBun (0.445 g, 52 %) and Me3SiSiMe3 (6 mg, 1 %)
were detected.
2.8 Reaction of 1 with Me3SiI
1.73 g of 1 (4.34 mmol) were suspensed in 100 ml of THF, and at
ambient temperature 1.00 ml (7.00 mmol) Me3SiI were added un-
der vigorous stirring. The color changed immediately from dark
violet to brown. After 2 h the formation of a gray slurry was fin-
ished. Stirring was continued for another 20 h at ambient tempera-
ture, and the precipitate was separated from the light blue solution
by filtration. In the cold (ca. 4 °C), 3.25 g (92 %) nearly colorless
(very pale blue), needlelike crystals of NdI3(THF)4 (2) formed while
Z. Anorg. Allg. Chem. 2007, 256Ϫ260
2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
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