Synthesis and characterization of well-defined aluminum-containing heterobimetallic selenides

Article abstract of DOI:10.1021/ic700945a

A series of novel aluminum heterobimetallic selenides were reported. The reaction of LAl(SeH)₂ (1) with LiN(SiMe₃)₂ resulted in the formation of [LAl(SeLi)₂(THF)₂] (2) (L = HC(CMeNAr)₂, Ar = 2,6-iPr₂C₆H₃). Compound 2 reacted with Me₂GeCl₂, Ph₂GeCl ₂, Cp₂TiCl₂, and Cp₂ZrCl ₂, respectively, to produce LAl(μ-Se)₂GeMe₂ (3), LAl(μ-Se)₂GePh₂ (4), LAl(μ-Se) ₂TiCp₂ (5), and LAl(μ-Se)₂ZrCp₂ (6) in moderate yields. Compounds 2-6 were characterized by elemental analysis, NMR, and electron impact-MS. The X-ray single-crystal structure of 3 is reported and confirms the spirocyclic arrangement of the aluminum atom within the six-membered AlN₂C₃ and four-membered AlSe₂Ge rings.

Full text of DOI:10.1021/ic700945a

Inorg. Chem. 2007, 46, 7093−7096
Synthesis and Characterization of Well-Defined Aluminum-Containing
Heterobimetallic Selenides†
Zhi Yang,‡ Xiaoli Ma,‡ Herbert W. Roesky,*,‡ Ying Yang,§ Jorg Magull,‡ and Arne Ringe‡
1
Institut fu¨r Anorganische Chemie der Georg-August-UniVersita¨t Go¨ttingen, Tammannstrasse 4,
D-37077 Go¨ttingen, Germany, and School of Chemistry and Chemical Engineering, Central South
UniVersity, 410083 Changsha, P.R. China
Received May 16, 2007
A series of novel aluminum heterobimetallic selenides were reported. The reaction of LAl(SeH)2 (1) with LiN(SiMe3)2
resulted in the formation of [LAl(SeLi)2(THF)2] (2) (L HC(CMeNAr)2, Ar 2,6-iPr2C6H3). Compound 2 reacted
with Me2GeCl2, Ph2GeCl2, Cp2TiCl2, and Cp2ZrCl2, respectively, to produce LAl( -Se)2GeMe2 (3), LAl( -Se)2GePh2
(4), LAl( -Se)2TiCp2 (5), and LAl( -Se)2ZrCp2 (6) in moderate yields. Compounds 2 6 were characterized by elemental
)
)
µ
µ
µ
µ
−
analysis, NMR, and electron impact-MS. The X-ray single-crystal structure of 3 is reported and confirms the spirocyclic
arrangement of the aluminum atom within the six-membered AlN2C3 and four-membered AlSe2Ge rings.
Introduction
application, the synthesis of aluminum heterobimetallic
selenides is an interesting subject. In 2000, [LAl(SeH)2] (1)
(L ) HC(CMeNAr)2, Ar ) 2,6-iPr2C6H3) was reported by
our group.8 This unusual species led us to explore a
successful route to the synthesis of heterobimetallic selenides
by metathesis of the SeH protons with metal atoms. Although
heterobimetallic sulfides have been successfully prepared,3a
it is much more difficult to synthesize the corresponding
selenide compounds for the reason of the weak metal-
selenium bonds, which often lead to the cleavage of the
Heterobimetallic chalcogen compounds have attracted
much interest because of inherent fundamental chemistry in
addition to their potential applications.1 Aluminum is the
most abundant metal in the earth’s crust, and many aluminum-
containing heterobimetallic oxides have been synthesized and
characterized.2 In recent years, a few heterobimetallic sulfides
have also been reported.3 However, there is still no structur-
ally characterized aluminum heterobimetallic selenide known,
for the reasons of limited synthetic methods and the
compounds’ thermodynamic instability. Because of its
potential for biomedical,4 catalytic,5 and conducting6 ap-
plications and as a precursor for a chemical vapor deposition7
(3) (a) Jancik, V.; Roesky, H. W.; Neculai, D.; Neculai, A. M.; Herbst-
Irmer, R. Angew. Chem., Int. Ed. 2004, 43, 6192-6196. (b) Yang,
Z.; Ma, X.; Oswald, R. B.; Roesky, H. W.; Cui, C. M.; Schmidt, H.-
G.; Noltemeyer, M. Angew. Chem., Int. Ed. 2006, 45, 2277-2280.
(c) Yang, Z.; Ma, X.; Jancik, V.; Zhang, Z.; Roesky, H. W.; Magull,
J.; Noltemeyer, M.; Schmidt, H.-G.; Cea-Olivares, R.; Toscano, R.
A. Inorg. Chem. 2006, 45, 3312-3315.
(4) (a) Scott, M. L.; Martin, J. L.; Shapiro, J. R.; Klayman, D. L.; Shrift,
A. Organic Selenium Compounds: Their Chemistry and Biology;
Wiley-Interscience: New York, 1973; Chapter 13. (b) Lim, B. S.;
Willer, M. W.; Miao, M.; Holm, R. H. J. Am. Chem. Soc. 2001, 123,
8343-8349. (c) Sung, K.-M.; Holm, R. H. Inorg. Chem. 2001, 40,
4518-4525. (d) Bray, R. C.; Adams, B.; Smith, A. T.; Bennett, B.;
Bailey, S. Biochemistry 2000, 39, 11258-11269.
(5) (a) Wang, K.; Stiefel, E. I. Science 2001, 291, 106-109. (b) Kunkely,
H.; Vogler, A. Inorg. Chim. Acta 2001, 319, 183-186.
(6) (a) Kobayashi, N.; Naito, T.; Inabe, T. Synth. Met. 2001, 120, 1055-
1056. (b) Kato, R.; Fujiwara, M.; Kashimura, Y.; Yamaura, J. Synth.
Met. 2001, 120, 675-678. (c) Batsanov, A. S.; Bryce, M. R.; Dhindsa,
A. S.; Howard, J. A. K.; Underhill, A. E. Polyhedron 2001, 20, 537-
540.
(7) Reviews: (a) Barron, A. R. AdV. Mater. Opt. Electron. 1995, 5, 245-
258. (b) Atwood, J. L. In Coordination Chemistry of Aluminum;
Robinson, G. H, Ed.; VCH: New York, 1993; pp 99 and 197-232.
(8) Cui, C.; Roesky, H. W.; Hao, H.; Schmidt, H.-G.; Noltemeyer, M.
Angew. Chem., Int. Ed. 2000, 39, 1815-1817.
* To whom correspondence should be addressed. E-mail: hroesky@
gwdg.de. Fax: (+49) 551-39-3373.
† Dedicated to Professor L. F. Tietze on the occasion of his 65th birthday.
‡ Universita¨t Go¨ttingen.
§ Central South University.
(1) (a) Takeda, N.; Tokitoh, N.; Okazaki, R. Top. Curr. Chem. 2003, 231,
153-202. (b) Dubois, M. R. Chem. ReV. 1989, 89, 1-9. (c) Copere´t,
C.; Chabanas, M.; Saint-Arroman, R. P.; Basset, J.-M. Angew. Chem.,
Int. Ed. 2003, 42, 156-181. (d) Sinonnet-Je´gat, C.; Se´cheresse, F.
Chem. ReV. 2001, 101, 2601-2611. (e) Draganjac, M.; Rauchfuss, T.
B. Angew. Chem., Int. Ed. Engl. 1985, 24, 742-757. (f) Mu¨ller, A.;
Jaegermann, W.; Enemark, J. H. Coord. Chem. ReV. 1982, 46, 245-
280. (g) Mu¨ller, A.; Diemann, E.; Jostes, R.; Bo¨gge, H. Angew. Chem.,
Int. Ed. Engl. 1981, 20, 934-954. (h) Coucouvanis, D. AdV. Inorg.
Chem. 1998, 45, 1-73. (i) Kolis, J. W. Coord. Chem. ReV. 1990, 105,
195-219. (j) Mu¨ller, A. Polyhedron 1986, 5, 323-340. (k) Okazaki,
R. Phosphorus, Sulfur Silicon Relat. Elem. 2001, 168, 41-50.
(2) See for example: (a) Bai, G.; Singh, S.; Roesky, H. W.; Noltemeyer,
M.; Schmidt, H.-G. J. Am. Chem. Soc. 2005, 127, 3449-3455. (b)
Chai, J.; Jancik, V.; Singh, S.; Zhu, H.; He, C.; Roesky, H. W.;
Schmidt, H.-G.; Noltemeyer, M.; Hosmane, N. S. J. Am. Chem. Soc.
2005, 127, 7521-7528.
10.1021/ic700945a CCC: $37.00
Published on Web 07/03/2007
© 2007 American Chemical Society
Inorganic Chemistry, Vol. 46, No. 17, 2007 7093

Yang et al.
Scheme 1. Preparation of Compounds 2-6
1 M in D2O): δ 116.27. Anal. Calcd for C37H57AlLi2N2O2Se2
(760.66): C, 58.42; H, 7.55; N, 3.68. Found: C, 58.51; H, 7.58;
N, 3.73.
Preparation of LAl(µ-Se)2GeMe2 (3). A solution of Me2GeCl2
(0.17 g, 1 mmol) in THF (10 mL) was added dropwise to a
suspension of 2 (0.76 g, 1 mmol) in THF (20 mL) at - 30 °C.
After the addition was complete, the reaction mixture was allowed
to warm to room temperature. The solvent was removed in vacuo.
The solid was extracted with toluene (30 mL), and the toluene was
removed in vacuo. The residue was washed with cold n-hexane to
yield solid 3, which was isolated as a white powder. Yield: 0.60
g (85%); mp, 251 °C. EI-MS: m/z (%) 706 (33) [M+], 691 (100)
[M+ - Me]. 1H NMR (500.13 MHz, C6D6, 25 °C, TMS): δ 7.18-
3
7.12 (m, 6 H, Ar-H), 4.84 (s, 1 H, γ-H), 3.50 (sept, JH-H ) 6.8
3
Hz, 4 H, CHMe2), 1.60 (d, JH-H ) 6.8 Hz, 12 H, CHMe2), 1.55
(s, 6 H, Me), 1.12 (d, 3JH-H ) 6.8 Hz, 12 H, CHMe2), 0.67 (s, 6 H,
Me-Ge). 13C NMR (125.77 MHz, C6D6, 25 °C, TMS): δ 170.50
(CN), 144.98, 139.50, 127.81, 124.76 (p-, m-, o-, and i-C of Ar),
98.43 (γ-C), 28.16 (CHMe2), 25.94 (CHMe2), 24.91 (CHMe2), 24.10
(Me), 11.49 (Ge-Me). 27Al NMR (78.21 MHz, CDCl3, 25 °C,
AlCl3, 1 M in D2O): δ 95.41. 77Se NMR (95.37 MHz, C6D6,
25 °C, SeMe2, 1 M in C6D6): -180.65. Anal. Calcd for C31H47-
AlGeN2Se2 (705.20): C, 52.53; H, 6.69; N, 3.96. Found: C, 53.86;
H, 7.03; N, 4.06. The slight differences in the found and calculated
analytical data are due to the extreme moisture sensitivity of the
product.
M-Se (M ) metal) bond. The successful synthesis of the
compound [LAl(SeLi)2(THF)2] (2)9 (L ) HC(CMeNAr)2, Ar
) 2,6-iPr2C6H3) opened the door to effectively prepare
aluminum-containing heterobimetallic selenides. From the
starting material 2, we prepared a number of stable aluminum
heterobimetallic selenides of composition LAl(µ-Se)2GeMe2
(3), LAl(µ-Se)2GePh2 (4), LAl(µ-Se)2TiCp2 (Cp ) C5H5) (5),
and LAl(µ-Se)2ZrCp2 (6) in high yield (Scheme 1). These
systems include main-group metals as well as transition
metals. They are well-defined, and 3 is the first structurally
characterized organoaluminum heterobimetallic selenide to
date.
Preparation of LAl(µ-Se)2GePh2 (4). Preparation was made like
that of 3 from Ph2GeCl2 (0.30 g, 1 mmol) and 2 (0.76 g, 1 mmol).
Product 4 was isolated as white powder. Yield: 0.75 g (90%); mp,
230 °C. EI-MS: m/z (%) 830 (93) [M+], 753 (100) [M+ - Ph]. 1H
NMR (500.13 MHz, C6D6, 25 °C, TMS): δ 7.65-7.64 (dd, 2 H,
GePh), 7.38-7.37 (dd, 4 H, GePh), 7.15-7.12 (m, 6 H, Ar-H),
7.03-6.98 (m, 4 H, GePh), 4.85 (s, 1 H, γ-H), 3.49 (sept, 3JH-H
)
Experimental Section
6.8 Hz, 4 H, CHMe2), 1.55 (s, 6 H, Me), 1.42 (d, 3JH-H ) 6.8 Hz,
12 H, CHMe2), 0.95 (d, 3JH-H ) 6.8 Hz, 12 H, CHMe2). 13C NMR
(125.77 MHz, C6D6, 25 °C, TMS): δ 170.86 (CN), 144.88, 139.45,
128.97, 124.90 (p-, m-, o-, and i-C of Ar), 140.25, 134.01, 133.75,
129.89 (p-, m-, o-, and i-C of SePh), 98.63 (γ-C), 29.27 (CHMe2),
25.58 (CHMe2), 25.45 (CHMe2), 24.09 (Me). 27Al NMR (78.21
MHz, C6D6, 25 °C, AlCl3, 1 M in D2O): δ 94.61. No satisfactory
analytical data was obtained due to the extreme moisture sensitivity
of the product.
General Procedures. All manipulations were carried out under
a purified nitrogen atmosphere using Schlenk techniques or inside
a Mbraun MB 150-GI glovebox. All solvents were distilled from
Na/benzophenone ketyl prior to use. Commercially available
chemicals were purchased from Aldrich or Fluka and used as
received. Elemental analyses were performed by the Analytisches
Labor des Instituts fu¨r Anorganische Chemie der Universita¨t
Go¨ttingen. 1H, 7Li, 13C, 27Al, and 77Se NMR spectra were recorded
on Bruker AM 200, 300, and 500 spectrometers. Electron impact
(EI) mass spectra were measured on Finnigan MAT 8230 or Varian
MAT CH5 instruments. Melting points were measured in sealed
glass tubes and were not corrected.
Preparation of LAl(µ-Se)2TiCp2 (5). A solution of Cp2TiCl2
(0.25 g, 1 mmol) in THF (10 mL) was added dropwise to a
suspension of 2 (0.76 g, 1 mmol) in THF (20 mL) at - 30 °C.
After the addition was complete, the reaction mixture was allowed
to warm to room temperature. The solvent was removed in vacuo.
The solid was extracted with toluene (30 mL), and the toluene was
removed in vacuo; 5 was isolated as a red powder. Yield: 0.72 g
(92%); mp, 290 °C (dec). EI-MS: m/z (%) 780 (15) [M+], 715
(100) [M+ - Cp]. 1H NMR (200.13 MHz, C6D6, 25 °C, TMS): δ
7.39-7.38 (m, 6 H, Ar-H), 5.85 (s, 10 H, Cp-H), 4.77 (s, 1 H,
Preparation of LAl(SeLi)2(THF)2 (2). Compounds LAl(SeH)2
(1) (3.64 g, 6 mmol) and LiN(SiMe3)2 (2.99 g, 12 mmol) were
mixed as solids in a flask, and subsequently, cold THF (60 mL,
0 °C) was added. The reaction mixture was cooled to -30 °C and
maintained at this temperature for 15 min under vigorous stirring.
After filtration, the solid was dried in vacuo and 2 was obtained as
a pale yellow powder. Yield: 3.53 g (77.4%); mp, >400 °C (dec).
1H NMR (300.13 MHz, CDCl3, 25 °C, TMS): δ 7.10-7.00 (m, 6
γ-H), 3.60 (sept, 3JH-H ) 6.8 Hz, 4 H, CHMe2), 1.95 (d, 3JH-H
)
6.8 Hz, 12 H, CHMe2), 1.58 (s, 6 H, Me), 1.08 (d, 3JH-H ) 6.8 Hz,
12 H, CHMe2). 13C NMR (50.33 MHz, CDCl3, 25 °C, TMS): δ
169.2 (CN), 145.5, 139.9, 127.3, 124.4 (p-, m-, o-, and i-C of Ar),
118.1 (Cp-C), 94.8 (γ-C), 28.9 (CHMe2), 25.9 (CHMe2), 25.4
(CHMe2), 24.7 (Me). 27Al NMR (78.21 MHz, CDCl3, 25 °C, AlCl3,
1 M in D2O): δ 112.54. 77Se NMR (95.43 MHz, CDCl3, 25 °C,
SeMe2, 1 M in CDCl3): 318.90. Anal. Calcd for C39H51AlN2Se2Ti
(780.63): C, 60.01; H, 6.59; N, 3.59. Found: C, 59.05; H, 6.35;
N, 3.59.
3
H, Ar-H), 5.10 (s, 1 H, γ-H), 3.87 (sept, JH-H ) 6.8 Hz, 4 H,
CHMe2), 3.40 (m, 8 H, O(CH2CH2)2), 1.68 (m, 8 H, O(CH2CH2)2),
3
1.54 (s, 6 H, Me), 1.22 (d, JH-H ) 6.8 Hz, 12 H, CHMe2), 1.02
(d, 3JH-H ) 6.8 Hz, 12 H, CHMe2). 13C NMR (125.77 MHz, CDCl3,
25 °C, TMS): δ 168.15 (CN), 145.47, 142.89, 125.47, 123.64 (p-,
m-, o-, and i-C of Ar), 98.67 (γ-CH), 68.04 (O(CH2CH2)2), 28.10
(CH(CH3)2), 26.91 (O(CH2CH2)2)), 25.31 (CH(CH3)2), 24.56 (CH-
(CH3)2), 24.46 (CH3). 7Li NMR (116.64 MHz, CDCl3, 25 °C, LiCl,
1 M in D2O): δ 1.26. 27Al NMR (78.21 MHz, CDCl3, 25 °C, AlCl3,
Preparation of LAl(µ-Se)2ZrCp2 (6). Preparation was made like
that of 5 from Cp2ZrCl2 (0.29 g, 1 mmol) and 2 (0.76 g, 1 mmol).
Product 6 was isolated as an orange powder. Yield: 0.73 g (88%);
mp, 340 °C (dec.). EI-MS: m/z (%) 824 (89) [M+], 759 (100) [M+
(9) [LAl (SeLi)2(THF)2] is the molecular formula of compound 2. It
probably has an oligomer [LAl(SeLi)2(THF)2]n composition.
7094 Inorganic Chemistry, Vol. 46, No. 17, 2007

NoWel Aluminum Heterobimetallic Selenides
1
- Cp]. H NMR (200.13 MHz, CDCl3, 25 °C, TMS): δ 7.35-
7.23 (m, 6 H, Ar-H), 5.88 (s, 10 H, Cp-H), 5.05 (s, 1 H, γ-H),
3.40 (sept, 3JH-H ) 6.8 Hz, 4 H, CHMe2), 1.90 (s, 6 H, Me), 1.68
(d, 3JH-H ) 6.8 Hz, 12 H, CHMe2), 1.17 (d, 3JH-H ) 6.8 Hz, 12 H,
CHMe2). 13C NMR (50.33 MHz, CDCl3, 25 °C, TMS): δ 170.11
(CN), 145.51, 139.62, 127.39, 124.46 (p-, m-, o-, and i-C of Ar),
114.33 (Cp-C), 95.79 (γ-C), 28.83 (CHMe2), 25.54 (CHMe2),
25.49 (CHMe2), 24.77 (Me). 27Al NMR (78.21 MHz, CDCl3,
25 °C, AlCl3, 1 M in D2O): δ 112.89. 77Se NMR (95.39 MHz,
CDCl3, 25 °C, SeMe2, 1 M in CDCl3): 41.96. Anal. Calcd for
C39H51AlN2Se2Zr (823.97): C, 56.85; H, 6.24; N, 3.40. Found: C,
56.85; H, 6.14; N, 3.19.
Single-Crystal X-ray Structure Determination and Refine-
ment. The crystallographic data for compound 3 was collected on
a STOE IPDS II array detector system with a four-circle instrument.
Graphite-monochromated Mo K radiation (λ ) 0.71073 Å) was
used. The structures were solved by direct methods (SHELXS-90)10
and refined against F2 using SHELXL-97.11 Hydrogen atoms were
included in geometrically idealized positions and refined isotropi-
cally using the riding model with Uiso tied to the Uiso of the parent
atoms.
Figure 1. Molecular structure of 3. Thermal ellipsoids are drawn at the
50% level. The solvent molecule and hydrogen atoms are omitted for clarity.
Selected bond distances (Å) and angles (deg): Al(1)-N(1) 1.897(3), Al-
(1)-N(2) 1.880(3), Al(1)-Se(1) 2.356(1), Al(1)-Se(2) 2.367(1), Ge(1)-
Se(1) 2.350(1), Ge(1)-Se(2) 2.350(1), Ge(1)-C(31) 1.942(3), Ge(1)-C(30)
1.943(3); Se(1)-Al(1)-Se(2) 99.16(3), N(1)-Al(1)-N(2) 98.03(11), Al-
(1)-Se(1)-Ge(1) 79.99(2), Al(1)-Se(2)-Ge(1) 79.75(2), Se(2)-Ge(1)-
Se(1) 99.844(16), C(31)-Ge(1)-C(30) 111.10(17).
Results and Discussion
Compound 2 was prepared by the reaction of 1 with 2
equiv of LiN(SiMe3)2 at low temperature. Compounds 3-6
were synthesized by adding dropwise solutions of Me2GeCl2,
Ph2GeCl2, Cp2TiCl2, and Cp2ZrCl2 in THF, respectively, to
2 suspended in THF at -30 °C. Compound 2 is sparingly
soluble in THF at low temperature. However, after adding
Me2GeCl2, Ph2GeCl2, Cp2TiCl2, and Cp2ZrCl2, respectively,
the suspension became clear and the light yellow color very
quickly turned colorless (for Me2GeCl2 and Ph2GeCl2), red
(for Cp2TiCl2), and orange (for Cp2ZrCl2). This is an
indication for the progress of the reaction. Compounds 3 and
4 are colorless solids, whereas 5 is red and 6 is orange in
the solid state. All are well soluble in toluene, benzene, and
especially in chloroform.
the γ-H proton, respectively. The EI mass spectra of 3-6
(m/z ) 706, 830, 780, and 824) show the parent ions [M+]
with their isotopic patterns. The isotopic patterns of com-
pounds 3-6 as determined by EI-MS spectrometry agree
very well with the results of calculation, which also provide
solid proof of the identities of these compounds (Figures S1-
S8, see the Supporting Information).
The composition of 3 was assigned by single-crystal X-ray
structural analysis. Colorless crystals of 3 were obtained from
toluene at 4 °C. Compound 3 crystallizes in the monoclinic
space group P21/c.12 The molecular structure of 3 is shown
in Figure 1. The characteristics of 3 are the (µ-Se)2 bridges
between the aluminum and germanium atoms, generating an
unambiguous novel heterobimetallic selenide moiety. The
Al-Se bond lengths (2.356 and 2.367 Å) are a little longer
than those in 1 (2.331 and 2.340 Å)8 and just in the range of
those in Al(µ-Se)2Al (2.352-2.394 Å).13 The replacement
of the SeH protons by Ge has some influence on the Al-Se
bond length because the partial negative charge on the Se
atom in 3 has been transferred to the Se-Ge bond, which
led to the lower electron density and an elongation of the
Al-Se(H) bond. The Ge-Se bond lengths (2.350 Å) are also
in accordance with those reported (2.357-2.370 Å).14 The
AlS2Ge four-membered ring is essentially planar, with the
sum of inner angles equal to about 360°. The angle at the
Compounds 2-6 were characterized by EI-MS spectrom-
1
7
etry, elemental analysis, H, 13C, Li, 27Al, and 77Se NMR
investigations, and single-crystal X-ray diffraction studies.
1
The H NMR spectra of 2-6 exhibit one set of resonances
for the ligand (L), respectively. The 1H NMR spectrum of 2
exhibits resonances around δ 4.0 and 1.6, which were
assigned to the THF molecules. From the ratio of integration
between THF with the ligand, it can be assumed that there
are two molecules of THF coordinated to the lithium atoms
in one LAL(SeLi)2 unit. There is no high-field (δ < 0 ppm)
1
resonance in the H NMR spectrum of 2; it clearly shows
the complete exchange of the protons in the starting material
of LAl(SeH)2 (1) by lithium atoms. There is a resonance (δ
) 1.26 ppm) in the 7Li NMR spectrum of 2, which indicates
1
the existence of lithium in compound 2. The H NMR
(12) Crystal data for 3: C31H47AlGeN2Se2, Mr ) 705.20, monoclinic, space
group P21/c, a ) 11.9939(10) Å, b ) 17.4552(9) Å, c ) 16.0281(13)
spectrum of 3 exhibits a Ge-Me resonance at δ 0.66 ppm
in a 6:1 ratio to that of the γ-H proton while 4 shows the
Ge-Ph resonances in ranges (δ 7.03 to 6.98, 7.38-7.37,
and 7.65-7.64) which are distinct from those of the Ar-H
resonances (δ 7.15-7.12 ppm). Compounds 5 and 6 exhibit
Cp resonances at δ 5.88 and 5.85 in a 10:1 ratio to that of
Å, R ) γ ) 90°, â ) 90.686(6)°, V ) 3355.3 Å3, Z ) 4, Fcalcd
)
1.396 Mg m-3, F(000) ) 1440, R(int) ) 0.0553, goodness-of-fit on
F2 ) 0.963; the R values are R1 ) 0.0301 and wR2 ) 0.0667 (I >
2σ(I)); the residual electron density ) 0.459/-0.437 e Å-3
.
(13) See for example: (a) Kumar, R.; Dick, D. G.; Ghazi, S. U.; Taghiof,
M.; Heeg, M. J.; Oliver, J. P. Organometallics 1995, 14, 1601-1607.
(b) Jancik, V.; Cabrera, M. M. M.; Roesky, H. W.; Herbst-Irmer, R.;
Neculai, D.; Neculai, A. M.; Noltemeyer, M.; Schmidt, H.-G. Eur. J.
Inorg. Chem. 2004, 3508-3512.
(14) See for example: (a) Unno, M.; Kawai, Y.; Shioyama, H.; Matsumoto,
H. Organometallics 1997, 16, 4428-4434. (b) Leung, W.-P.; So, C.-
W.; Wang, Z.-X.; Wang, J.-Z.; Mak, T. C. W. Organometallics 2003,
22, 4305-4311.
(10) Sheldrick, G. M. SHELXS-90, Program for Structure Solution; Acta
Crystallogr., Sect. A 1990, 46, 467-473.
(11) Sheldrick, G. M. SHELXL-97, Program for Crystal Structure Refine-
ment; University of Go¨ttingen: Go¨ttingen, Germany, 1997.
Inorganic Chemistry, Vol. 46, No. 17, 2007 7095

Yang et al.
aluminum center (99.16°) is almost equal to the angle at
germanium (99.84°), and the angles at the two selenium
centers are almost equal (79.99° and 79.75°) to each other.
Acknowledgment. We are grateful for financial support
by the Fonds der Chemischen Industrie and the Go¨ttinger
Akademie der Wissenschaften.
Conclusion
Supporting Information Available: Figures S1-S8 (PDF), as
well as CIF data for 3. This material is available free of charge via
the Internet at http://pubs.acs.org.
In summary, we discovered a new strategy for the
preparation of aluminum heterobimetallic selenides and
prepared the first series of well-defined aluminum hetero-
bimetallic selenides.
IC700945A
7096 Inorganic Chemistry, Vol. 46, No. 17, 2007