B. Wrackmeyer et al. / Inorganic Chemistry Communications 7 (2004) 412–416
415
3. Experimental
filtrate in vacuo (0.01 Torr). The yellow–orange residue
(440 mg, 87%) contained >85% of 5 and a small amount
of 6, along with minor quantities of unidentified mate-
rials (1H and 29Si NMR). The solid was dissolved in a
mixture of pentane/hexane (1:1) (50 mL), filtered and the
filtrate was collected in a Schlenk tube. In this tube, at
)30 °C, a few orange prisms of 5 crystallised at the glass
wall. These crystals (m.p. 98–99 °C) were suitable for X-
ray structure determination. 1H NMR (CD2Cl2, 23 °C):
All preparative work and the handling of the samples
of 1, 5 and 6 was carried out observing necessary pre-
cautions to exclude air and traces of moisture. Carefully
dried solvents and oven-dried glassware were used
throughout. 1,10-Diaminoferrocene 1 was prepared ac-
cording to the published procedure [2]. NMR mea-
surements in solution (5 mm o.d. tubes): Bruker
1
ARX 250: H (250.1 MHz), 13C (62.9 MHz), and 29Si
d ¼ 0.30 (s, 12H, MeSi), 0.77 (s, 4H, SiCH2), 2.510(br) (s,
0
NMR (49.7 MHz; refocused INEPT based on J(29Si,
2H, NH), 3.66, 3.75, 3.81 and 3.83 (all m, 8H2–5;2 ;5 ). 1H
2
1H) ¼ 7 Hz); chemical shifts are given relative to Me4Si
[d1H (C6D5CD2H) ¼ 2.08; (CDHCl2) ¼ 5.33; d13C
(C6D5CD3) ¼ 20.5; (CD2Cl2) ¼ 53.8], d29Si ¼ 0 [Me4Si
with N(29Si) ¼ 19.867184 MHz]. EI–MS spectra were
measured with a Finnigan MAT 8500 spectrometer
(ionisation energy 70 eV) with direct inlet. The melting
NMR (D8-toluene, 23 °C): d ¼ 0.26 (s, 12H, MeSi), 0.72
(s, 4H, SiCH2), 2.08 (br) (s, 2H, NH), 3.67 and 3.72 (m,
m, 6H, 2H, H2–5;2 –5;5 ).
0
0
3.2. Tetramethyl-1,6,2,5-diazadisila-½6ꢂferrocenophane 6
€
points (uncorrected) were determined using a Buchi 510
or a Stuart Scientific smp 3 melting point apparatus.
The solution of 5 in pentane/hexane (vide supra) was
kept for a longer time at )30 °C, and gold–orange nee-
dle-shaped crystals of 6 formed, which fell to the bottom
of the Schlenk tube, readily separated from 5 [180 mg of
6 (36%), m.p. 177–179 °C]. Single crystals for X-ray
structure analysis were obtained by recrystallisation
from D8-toluene at )20 °C in the NMR tube. 1H NMR
(CD2Cl2, 23 °C): d ¼ 0.08 (s, 12H, MeSi), 0.77 (s, 4H,
3.1. 1-Amino-10-ð2, 2, 5, 5-tetramethyl-1-aza-2, 5-disila-
cyclopent-1-ylÞferrocene 5
A suspension of 1,10-diaminoferrocene 1 (305 mg,
1.41 mmoL) in Et2O (30 mL) together with triethyl-
amine (0.47 mL, 3.36 mmoL) was prepared. The
suspension was cooled to 0 °C, and 1,2-bis(chlorodim-
ethylsilyl)ethane (304 mg, 1.41 mmoL) dissolved in Et2O
(10 mL) was added dropwise. The reaction mixture was
stirred at 0 °C for 1 h, and was then kept stirring for 4
days at room temperature. Insoluble materials were fil-
tered off, and volatile materials were removed from the
0
0
SiCH2), 2.52 (br) (s, 20H, NH), 3.61 (br) (m, 4H, H2;2 ;5;5 ),
0
1
3.73 (m, 4H, H3;3 ;4;4 ). H NMR (D8-toluene, 23 °C):
d ¼ 0.04 (s, 12H, MeSi), 0.58 (s, 4H, 0SiCH2), 2.03 (br) (s,
0
2H,0 N0H), 3.49 (br) (m, 4H, H2;2 ;5;5 ), 3.79 (m, 4H,
H3;3 ;4;4 ). C16H26FeN2Si2 (358.42): EI–MS: m/z (%) ¼
358 (100) [Mþ], 326 (13), 309 (8), 272 (8), 257 (9), 228 (8),
178 (15), 157 (13), 136 (15), 122 (15), 73 (60), 59 (63).
Table 2
Crystallographic data of the bis(amino)ferrocene 5 and [6]ferrocenophane 6
5
6
Formula
C16H26N2Si2Fe
358.42
C16H26N2Si2Fe
358.42
Formula weight
Crystal
Temperature
Orange prism
293(2) K
Orange platelet
293(2) K
Dimensions (mm)
Crystal system
Space group
0.20 ꢃ 0.16 ꢃ 0.16
Monoclinic
P21/c
0.30 ꢃ 0.28 ꢃ 0.08
Orthorhombic
P212121
Lattice parameters (pm, °)
a ¼ 1419:8ð3Þ
b ¼ 951:96ð19Þ
c ¼ 1494:2ð3Þ
b ¼ 116:85ð3Þ
1801.8(6)
a ¼ 742:77ð15Þ
b ¼ 1056:0ð2Þ
c ¼ 2410:5ð5Þ
Volume (10ꢁ6 pm3)
Z
Absorption coefficient l (mmꢁ1
Diffractometer
1890.7(7)
4
0.920
4
0.966
)
STOE IPDS I (Mo Ka, k ¼ 71; 073 pm), graphite monochromator
Measuring range (h)
Reflections collected
1–26
12086
2–26
9989
Independent reflections (I > 2rðIÞ)
Absorption correction
Refined parameters
3460 (Rint ¼ 0:0621)
3211 (Rint ¼ 0:1708)
Nonea
190
190
0.2499/0.1030
1.05/)0.61
WR2=R1 – value (I > 2rðIÞ)
0.1062/0.0484
0.45/)0.32
Max/min residual electron density (e pmꢁ3 10ꢁ6
)
a Absorption correction did not improve the data set.