Synthesis and crystal structures of [(iPr3P)2Cu(μ- ESiMe3)(InMe3)] (E = S, Se): Lewis acid-base adducts with chalcogen atoms in planar coordination

Article abstract of DOI:10.1002/ejic.201300768

The structures of [(iPr₃P)₂Cu(μ-SSiMe ₃)(InMe₃)] and [(iPr₃P)₂Cu(μ- SeSiMe₃)(InMe₃)] were determined by single-crystal X-ray diffraction. Both complexes are Lewis acid-base adducts of the InMe₃ acceptor and the chalcogen donor atom linking a Me₃Si group and a (iPr₃P)₂Cu moiety. They are very unstable under atmospheric conditions and decompose at ambient temperatures. Results of DFT calculations for these complexes and the related hypothetical [(Me ₃P)₂Cu(μ-SSiMe₃)(InMe₃)] compound show that the unusual planar coordination of the chalcogen atoms is due to steric crowding. Lewis acid-base adducts of trimethylindium and phosphane-stabilized copper(I) (trimethylsilyl)chalcogenolates were synthesized and characterized by X-ray crystal structure determination. They are very unstable under atmospheric conditions and decompose at ambient temperatures. DFT calculations reveal that the unusual planar coordination of the chalcogen atoms is due to steric crowding. Copyright

Full text of DOI:10.1002/ejic.201300768

Job/Unit: I30768
/KAP1
Date: 20-08-13 17:25:30
Pages: 6
SHORT COMMUNICATION
DOI:10.1002/ejic.201300768
Synthesis and Crystal Structures of [(iPr3P)2Cu(μ-ESi-
Me3)(InMe3)] (E = S, Se): Lewis Acid–Base Adducts with
Chalcogen Atoms in Planar Coordination
Ralf Biedermann,[a] Oliver Kluge,[a] Daniel Fuhrmann,[a] and
Harald Krautscheid*[a]
Keywords: Lewis acids / Lewis bases / Chalcogens / Density functional calculations / Structure elucidation
The structures of [(iPr3P)2Cu(μ-SSiMe3)(InMe3)] and [(iPr3P)2-
Cu(μ-SeSiMe3)(InMe3)] were determined by single-crystal
X-ray diffraction. Both complexes are Lewis acid–base ad-
ducts of the InMe3 acceptor and the chalcogen donor atom
linking a Me3Si group and a (iPr3P)2Cu moiety. They are very
unstable under atmospheric conditions and decompose at
ambient temperatures. Results of DFT calculations for these
complexes and the related hypothetical [(Me3P)2Cu(μ-SSi-
Me3)(InMe3)] compound show that the unusual planar coor-
dination of the chalcogen atoms is due to steric crowding.
(R = alkyl, phenyl; E = S, Se, Te) that carry an ESiMe3
group that coordinates terminally to the copper atom.[10]
These complexes are intermediates in the formation of cop-
per–chalcogenide clusters and are powerful starting materi-
als for further reactions with other metal compounds. They
are stable only at low temperatures; at room temperature
they react under cleavage of the second E–SiMe3 bond.
Herein, we present the crystal structures of such mononu-
clear complexes as adducts with InMe3, which may repre-
sent the first intermediates in the formation of organome-
tallic copper–indium–chalcogenide clusters.
Introduction
The donor–acceptor bond in Lewis acid–base adducts of
group 13 organometallic compounds and the chalcogen
atoms S and Se is relatively weak, as these chalcogen atoms
are only moderate donors and the organic groups at the
metal atom diminish their acceptor ability.[1] Consequently,
structural reports of such adducts are very scarce. The so-
lid-state structures of thioether adducts with AlMe3 and
InMe3,[2] organometallic complexes with two Al or Ga
atoms coordinating a SMe– or SPh– moiety,[3] and some
corresponding intramolecular stabilized adducts with S do-
nor atoms[4] have been reported. The first adduct between
TlMe3 and a S donor atom was presented recently,[5a] and
so far, the only structurally elucidated example for an Se
atom coordinating a group 13 purely organometallic unit is
the anion [MeSe(AlMe3)3]–.[6]
In our investigations concerning organometallic single-
source precursors for the deposition of ternary semi-
conductors used for thin-film solar cells,[7] we follow the
concept of the reaction of E(SiMe3)2 (E = S, Se) with phos-
phane-coordinated copper(I) acetate under cleavage of E–
SiMe3 bonds and the formation of the volatile Me3SiOAc
side product. Applying this method, Fenske, Corrigan et al.
synthesized a broad variety of metal chalcogenide clus-
ters.[8] It was also possible to incorporate group 13 metal
atoms into the clusters through the use of GaCl3 and InCl3
as additional reagents.[9] Corrigan et al. isolated mononu-
clear complexes of the general formula [(R3P)3CuESiMe3]
Results and Discussion
In reactions of InMe3 with in situ generated silylchalco-
genolate complexes of the type [(iPr3P)nCuESiMe3] (E = S,
Se), we expected cleavage of the E–SiMe3 bond with elimi-
nation of tetramethylsilane (TMS) as a side product[5] and
the formation of a molecule with a [(iPr3P)nCu–E–InMe2]
motif, which should oligomerize to rings or clusters to
achieve tetrahedral coordination of the indium atom. As it
turned out, TMS was not formed in this reaction, as shown
by NMR spectroscopy after the addition of InMe3 to a
chilled solution containing [(iPr3P)nCuESiMe3]. Instead, we
obtained simple adducts, in which InMe3 is coordinated by
the chalcogen atom. After evaporation of the solvent and
volatile side products at low temperature, we were able to
grow colorless crystals of [(iPr3P)2Cu(μ-ESiMe3)(InMe3)]
(1: E = S, 2: E = Se), which are very sensitive towards air
and moisture and decompose at temperatures above –15 °C.
Complex 1 crystallizes in the Pna21 space group with three
molecules in the asymmetric unit. Selenium analogue 2
crystallizes in the acentric Cc space group with one mo-
[a] Institut für Anorganische Chemie, Universität Leipzig,
Johannisallee 29, 04103 Leipzig, Germany
E-mail: krautscheid@rz.uni-leipzig.de
Homepage: www.uni-leipzig.de/~chemiehk
Supporting information for this article is available on the
WWW under http://dx.doi.org/10.1002/ejic.201300768.
Eur. J. Inorg. Chem. 0000, 0–0
1
© 0000 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

Job/Unit: I30768
/KAP1
Date: 20-08-13 17:25:30
Pages: 6
www.eurjic.org
SHORT COMMUNICATION
lecule per asymmetric unit.[11] Figure 1 shows the molecular
If bond lengths and angles of 1 and 2 are compared with
structure of one of the three crystallographically indepen- those of the copper trimethylsilylchalcogenolates [(R3P)3-
dent molecules of 1, as determined by single-crystal X-ray CuESiMe3],[10] we note that the E–Si bonds do not show
diffraction. The two other independent molecules of 1 differ significant deviation. The Cu–P and Cu–E bonds are
in the angles between the (P1, P2, Cu) and (Si, S, In) planes, slightly shorter in 1 and 2 (3–4 and 6–7 pm, respectively),
which are arranged approximately perpendicular to each as in 1 and 2 the Cu atoms have a lower coordination
other (76–89°). The structural motif of selenium compound number than the tetrahedrally coordinated copper atoms in
2 is almost identical. Table 1 presents structural details of [(R3P)3CuESiMe3]. The Cu–E–Si angles are almost the
the molecules of 1 and 2. The trigonal planar coordination same as those in Corrigan’s complexes (123°).
of the copper atom is in accordance with the steric demand
One of the free electron pairs of the chalcogen atom is
of the bulky iPr3P ligands. Unusual is the planar environ- used in the formation of a Lewis acid–base adduct with the
ment of the chalcogen atom, which connects the copper electron-deficient InMe3 moiety. In a comparable way, SO2
atom with the indium and silicon atoms. Typically, bridging adducts have been observed in [(Ph2MeP)3Cu(μ-SPh)(SO2)]
chalcogenolate ligands have a pyramidal coordination,[12] and related selenium complexes.[14] Given the absence of re-
although some exceptions are known. A detailed investiga- ports on the structures of adducts between indium triorgan-
tion of such an exception in the case of phosphane-stabi- yls and a single S or Se donor atom, the In–E bond lengths
lized copper(I) phenylchalcogenolate complexes was re- lack a direct comparison. As can be expected from induc-
cently reported.[13]
tive effects,[1c] the In–E bond lengths in the indium dimethyl
[(Me2InEPh)n] compounds (≈260 pm reported for E = S
and 272 pm for E = Se)[5] are slightly shorter than those in
1 and 2. Much longer In–S distances (297 and 313 pm) were
observed in the polymeric [Me3In(1,4-C4H8S2)] adduct, in
which planar Me3In groups are bridged by the cyclic 1,4-
C4H8S2 thioether.[2c] In 1 and 2, the In atoms deviate by
45–48 pm from the C3 planes because of interaction with
only one chalcogen atom. The Cu–E–In angles are around
127° in 1 and 124° in 2, whereas the In–E–Si angles are
compressed to approximately 108°. Notably, a large M–E–
M angle (in the present case M = Cu, In) is necessary to
provide sufficient overlap between the lone pairs of elec-
trons of the chalcogenolate ligand and the empty metal
atomic orbitals, if the chalcogen atom has a nearly planar
environment.[13]
To examine the assumption that the high steric demand
of the phosphane ligands causes the planarity of the chalco-
gen atoms, we performed DFT structure optimizations for
1, 2, and the hypothetical, less-crowded [(Me3P)2Cu(μ-SSi-
Figure 1. Molecular structure of 1. H atoms are omitted for clarity;
P, Cu, S, In, and Si atoms are drawn as 50% ellipsoids. A unit cell
plot of 1 as well as a depiction of the molecular structure of 2 are
available in the Supporting Information.
Table 1. Structural details of [(iPr3P)2Cu(μ-SSiMe3)(InMe3)] (1), [(iPr3P)2Cu(μ-SeSiMe3)(InMe3)] (2) (from crystal-structure determination
as well as DFT calculations), and the hypothetical [(Me3P)2Cu(μ-SSiMe3)(InMe3)] (3) complex (DFT calculations).
Distances and
1 (E = S)
3 (E = S)
2 (E = Se)[a]
2 (E = Se)
angles [pm and °]
molecule 1
molecule 2
molecule 3
DFT calcd.
DFT calcd.
DFT calcd.
Cu–E
In–E
Si–E
In–C (avg.)
Cu–P (avg.)
P1–Cu–P2
P1–Cu–E
P2–Cu–E
In–E–Si
Cu–E–In
Cu–E–Si
C–In–C (avg.)
(P1, P2, Cu)/(Si, E, In)
In out of (C,C,C) plane
Cu out of (P,P,E) plane
233.8(3)
263.8(3)
210.9(4)
220.1Ϯ0.8
226.5Ϯ0.8
136.6(1)
107.5(1)
115.8(1)
108.2(2)
126.5(1)
123.5(2)
115Ϯ4
232.9(3)
263.2(3)
211.5(4)
218Ϯ1
226Ϯ1
136.5(1)
108.0(1)
115.4(1)
108.2(1)
127.2(1)
123.6(2)
116Ϯ4
75.98(8)
46.63(7)
3.4(1)
231.0(3)
262.3(3)
212.7(5)
218Ϯ3
227.3Ϯ0.8
136.5(1)
109.1(1)
114.4(1)
109.3(2)
128.6(1)
122.0(2)
116Ϯ4
89.20(8)
45.0(1)
235.98
273.45
214.66
219.3Ϯ0.4
232.2Ϯ0.2
133.17
113.31
113.41
112.75
122.35
123.53
116.5Ϯ0.5
80.4
232.06
271.59
214.60
219Ϯ1
225Ϯ2
131.02
107.44
121.50
115.23
103.31
120.06
114Ϯ2
82.0
247.7/242.9(2)
276.4/273.4(2)
233.3/231.4(3)
220Ϯ4
226.3Ϯ0.3
137.87(9)
118.4/103.1(1)
103.6/119.0(1)
107.23(8)/108.8(1)
122.17(6)/125.41(9)
120.82(9)/123.8(1)
115Ϯ2
83.40/84.01(6)
47.6(7)
4.5(2)/3.0(2)
45.6(2)/20.5(4)
244.85
288.11
229.80
219.3Ϯ0.5
233.0Ϯ0.3
131.93
116.83
111.18
109.71
120.44
121.66
116.8Ϯ0.5
77.57
76.04(7)
47.40(7)
2.8(1)
41.1
4.0
16.2
42.0
2.7
63.1
39.7
3.2
41.8
1.1(1)
3.8(4)
E out of (In,Si,Cu) plane 18.5(4)
14.2(4)
[a] Se atom disordered with SOF = 0.6 and 0.4.
Eur. J. Inorg. Chem. 0000, 0–0
2
© 0000 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

Job/Unit: I30768
/KAP1
Date: 20-08-13 17:25:30
Pages: 6
www.eurjic.org
SHORT COMMUNICATION
Schlenk techniques or glove box methods were applied. iPr3P was
prepared by reaction of PCl3 with the iPrMgCl Grignard reagent.
(Me3Si)2E was synthesized from Na2E and Me3SiCl. CuOAc was
accessible by comproportionation of dehydrated Cu(OAc)2 and
copper powder in Ac2O/AcOH as described by Edwards et al.[18]
InMe3 was synthesized according to Brauer.[19] NMR experiments
were performed with a Bruker Avance DRX 400 spectrometer in
[D8]toluene at –15 °C; the toluene CD2H signals (δ =2.08 ppm)
Me3)(InMe3)] (3) complex. The results of these calculations
are presented in Table 1 together with the data from the
experimental crystal structure determinations. Most calcu-
lated values are in quite good agreement with the experi-
mental results.[15] Even the calculated out-of-plane param-
eters of the chalcogen atoms, only 16 pm in 1 and 42 pm in
2, are close to the results of the crystal-structure determi-
nation. The calculation with the smaller phosphane ligands
supports our assumption: the sulfur atom in 3 is more py-
ramidal, and the out-of-plane parameter of 63 pm illus-
trates this.
1
were used as reference for the H resonances.
[(iPr3P)2Cu(μ-ESiMe3)(InMe3)]: iPr3P (3.2 mmol) was added drop-
wise to a suspension of copper(I)acetate (184 mg, 1.5 mmol) in
THF (5 mL) at 0 °C. The obtained colorless solution was cooled
to –60 °C and added to S(SiMe3)2 (0.4 g, 2.2 mmol) at –60 °C. The
reaction solution remained colorless. After stirring for 1 h at
–60 °C, a precooled solution of InMe3 (1 m in THF, 1.5 mL,
1.5 mmol) was added slowly. The solution was stirred and allowed
to reach –20 °C over a period of 3 h. After storing the reaction
The 1H NMR, 13C NMR, and 31P NMR spectra
(–15 °C) of molecular complexes 1 and 2 in solution show
typical resonances of the InMe3, SiMe3, and PiPr3 groups
(Figures S3 and S4, Supporting Information). However, the
31P signals with chemical shifts close to those of pure PiPr3
are relatively broad, which is indicative of ligand-exchange mixture at this temperature for about 48 h, the solvent and volatile
side products (Me3SiOAc) were removed in vacuo at temperatures
below –20 °C to leave a colorless oil. For crystallization, the oil
was dissolved in precooled THF (3 mL) and then cold acetonitrile
(20 mL) was carefully added as a separate layer. After several days
at –20 °C, colorless crystals of 1 appeared, which decomposed im-
mediately under atmospheric conditions or if warmed up to ambi-
ent temperature, yield 30–50%. The product can be stored at low
processes in solution, and there is additional broadening of
the 31P signal caused by the quadrupole moment (I = 3/2)
of the copper isotopes. This is also observed for other CuI
phosphane complexes.[16] With decreasing temperature, the
31P signals become even broader and become resolved. The
1H NMR signals of the InMe3 groups are slightly shifted
downfield relative to the signals of a solution of pure InMe3
(δ = –0.18 ppm in [D6]benzene), and this is consistent with
only weak interactions of the InMe3 group with the donor
1
temperatures. H NMR (400 MHz, [D8]toluene, –15 °C): δ = –0.10
[s, 9 H, In(CH3)3], 0.48 [s, 9 H, Si(CH3)3], 0.99 [m, 36 H, PCH-
(CH3)2], 1.74 [m, 6 H, PCH(CH3)2] ppm. 13C NMR (100.6 MHz,
atoms.[17] At room temperature, solutions of 1 and 2 in tolu- [D8]toluene, –15 °C): δ = –7.7 [s, In(CH3)3], 6.6 [s, Si(CH3)3], 19.7
2
1
[d, JP,C = 4 Hz, PCH(CH3)2], 21.8 [d, JP,C = 9 Hz, PCH(CH3)2]
ppm. 31P{1H} NMR (161.9 MHz, [D8]toluene, –15 °C): δ = 16 (br.
s) ppm. 29Si NMR (79.5 MHz, [D8]toluene, –15 °C): δ = 9 (br. s)
ppm.
ene turn dark before a dark precipitate forms; the NMR
spectra indicate the formation of S(SiMe3)2 and Se(SiMe3)2,
respectively, whereas signals belonging to PiPr3 and InMe3
remain almost unchanged. The formation of TMS was not
observed.
2: Prepared by a procedure similar to that used for 1; Se(SiMe3)2
was used instead of S(SiMe3)2. 1H NMR ([D8]toluene, –15 °C): δ
= –0.14 [s, 9 H, In(CH3)3], 0.55 [s, 9 H, Si(CH3)3], 0.98 [m, 36 H,
PCH(CH3)2], 1.76 [m, 6 H, PCH(CH3)2] ppm. 13C NMR ([D8]tolu-
ene, –15 °C): δ = –8.0 [s, In(CH3)3], 6.8 [s, Si(CH3)3], 19.6 [s,
PCH(CH3)2], 21.8 [br. s, PCH(CH3)2] ppm. 31P{1H} NMR ([D8]-
toluene, –15 °C): δ = 14.4 (br.s) ppm. 29Si NMR ([D8]toluene,
–15 °C): δ = 7 (br. s) ppm.
Conclusions
Molecular compounds with a copper–chalcogen–indium
binding motif could be synthesized and characterized crys-
tallographically. We applied the concept of stabilizing cop-
per trimethylsilylchalcogenolates at low temperatures.[10]
The reaction of [(iPr3P)nCuESiMe3] with InMe3 did not re-
sult, as expected, in cleavage of the chalcogen–silicon bond
but in the formation of a simple Lewis acid–base adduct.
Adducts 1 and 2 have the rare structural feature of a chalco-
gen donor atom with (almost) planar coordination. This is
a consequence of the steric demand of the bulky phosphane
ligands that coordinate the copper atom. This explanation
is supported by DFT calculations. As the structures of 1
and 2 highlight, [(R3P)nCuESiMe3] molecules, which are
stable only at low temperatures, act as electron donors
towards Lewis acidic InMe3. In consecutive reactions, cop-
per–indium chalcogenide clusters are formed; a manuscript
reporting their synthesis and structures is in preparation.
X-ray Crystal Structure Determination: Crystals were selected, pre-
pared, and mounted on a glass fiber in mineral oil below –20 °C
under an N2 atmosphere. The mounted crystal was transferred im-
mediately into the cold flush at the diffractometer’s goniometer
head. The measurements were performed with a STOE IPDS 2T
at 180 K with Mo-Kα radiation monochromated with a graphite
single crystal. The structures were solved by direct methods (SIR-
92).[20] The obtained starting model was then refined with the least-
squares method (SHELXL-97).[21]
Due to the instability of 1 and 2 it was difficult to prepare single
crystals for structure determination. Slight decomposition on the
crystal surface was not avoidable during preparation. This reduced
the quality of the collected datasets. The crystal of complex 1 was
twinned non-merohedrically with a weighted intensity contribution
above 90% of the major domain. Because multidomain integration
of the diffracted intensities and hkl-f5-refinement did not improve
the result significantly, we decided to use just the reflections of the
major domain. The Flack parameter of the crystal of complex 2
indicated inversion twinning (ratio 0.6:0.4). The selenium atom is
disordered over two sites with occupancies of 0.6 and 0.4.
Experimental Section
Materials, Equipment, and Experimental Methods: All experiments
were performed under an inert atmosphere of nitrogen. Standard
Eur. J. Inorg. Chem. 0000, 0–0
3
© 0000 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

Job/Unit: I30768
/KAP1
Date: 20-08-13 17:25:30
Pages: 6
www.eurjic.org
SHORT COMMUNICATION
Eichhöfer, Z. Anorg. Allg. Chem. 2003, 629, 415–420; d) A.
Eichhöfer, D. Fenske, J. Olkowska-Oetzel, Z. Anorg. Allg.
Chem. 2004, 630, 247–251; e) R. Ahlrichs, N. R. M. Crawford,
A. Eichhöfer, D. Fenske, O. Hampe, M. M. Kappes, J. Olkow-
ska-Oetzel, Eur. J. Inorg. Chem. 2006, 345–350.
a) D. T. T. Tran, J. F. Corrigan, Organometallics 2000, 19,
5202–5208; b) A. Borecki, J. F. Corrigan, Inorg. Chem. 2007,
46, 2478–2484.
CCDC-756645 (for 1) and -756646 (for 2) contain the supplemen-
tary crystallographic data for this paper. These data can be ob-
tained free of charge from The Cambridge Crystallographic Data
Centre via www.ccdc.cam.ac.uk/data_request/cif.
Computational Details: The molecular structures of 1, 2, and hypo-
thetical adduct 3 were optimized at the B3LYP[22] level of density
functional theory without symmetry restrictions and were con-
firmed to be minima on the potential energy surface by frequency
analyses (no negative force constants). The calculations were per-
formed by using the Gaussian03 program package.[23] Basis sets
employed were 6-31G for hydrogen atoms; 6-311G(d) for carbon,
silicon, phosphorus, sulfur, copper, and selenium atoms; and the
LANL2DZ effective core potential basis set for indium atoms.[24]
[10]
[11]
Crystal data and structure refinement: 1 (C24H60CuInP2SSi):
STOE IPDS-2T diffractometer, Mm = 649.17 gmol–1, crystal
size 0.2ϫ0.2ϫ0.05 mm3, orthorhombic, space group Pna21
(No. 33),
a = 1699.64(4) pm, b = 1147.66(3) pm, c =
5260.2(2) pm, V = 10260.6(5)ϫ106 pm3, Z = 12, T = 180(2) K,
ρber = 1.261 gcm–3, μ = 1.495 mm–1, λ = 71.073 pm (Mo-Kα),
2θmax = 52°, 32786 measured, 15909 independent reflections,
Rint = 0.135, 13540 with IϾ2σ(I), 807 parameters, H atoms in
idealized positions, R1 (observed reflections) = 0.089, wR2 (all
data) = 0.247, Flack parameter x = 0.11(3), max./min. residual
electron density peaks 2.83/–1.45 e–/106 pm3. 2 (C24H60Cu-
Supporting Information (see footnote on the first page of this arti-
cle): Unit cell plot of 1; depiction of the molecular structure of 2;
1H NMR, 13C NMR, and 31P NMR spectra of solutions of 1 and
2.
InP2SeSi): STOE IPDS-2T diffractometer, Mm
=
696.07 gmol–1, crystal size 0.5ϫ0.4ϫ0.3 mm3, monoclinic,
space group Cc (No. 9), a = 1904.9(2) pm, b = 1174.40(6) pm,
c = 1740.2(1) pm, β = 118.880(6)°, V = 3409.0(4)ϫ106 pm3, Z
= 4, T = 180(2) K, ρber = 1.356 gcm–3, μ = 2.507 mm–1, λ =
71.073 pm (Mo-Kα), 2θmax = 50°, 9479 measured, 5460 inde-
pendent reflections, Rint = 0.102, 4758 with IϾ2σ(I), 284 pa-
rameters, H atoms in idealized positions, R1 (observed reflec-
tions) = 0.055, wR2 (all data) = 0.145, inversion twinning,
max./min. residual electron density peaks 1.82/–0.76 e–/
106 pm3.
Acknowledgments
Financial support by the University of Leipzig (PbF 1) and the
Graduate School BuildMoNa is gratefully acknowledged.
[1] a) G. E. Coates, J. Chem. Soc. 1951, 2003–2013; b) G. E.
Coates, R. A. Whitcombe, J. Chem. Soc. 1956, 3351–3354; c)
A. Haaland, Angew. Chem. 1989, 101, 1017–1032; Angew.
Chem. Int. Ed. Engl. 1989, 28, 992–1007.
[2] a) G. H. Robinson, H. Zhang, J. L. Atwood, Organometallics
1987, 6, 887–889; b) G. H. Robinson, S. A. Sangokoya, J. Am.
Chem. Soc. 1988, 110, 1494–1497; c) J. Blank, H.-D. Hausen,
W. Schwarz, J. Weidlein, J. Organomet. Chem. 1993, 443, 145–
151; d) H. Schumann, F. Girgsdies, S. Dechert, J. Gottfriedsen,
M. Hummert, S. Schutte, J. Pickardt, Z. Anorg. Allg. Chem.
2002, 628, 2625–2630.
[3] a) W. Uhl, R. Gerding, F. Hannemann, Z. Anorg. Allg. Chem.
1998, 624, 937–944; b) W. Uhl, M. Claesener, A. Hepp, Organo-
metallics 2008, 27, 2118–2122.
[4] a) J. A. Francis, S. G. Bott, A. R. Barron, Main Group Chem.
1999, 3, 53–57; b) C. Lustig, N. W. Mitzel, Organometallics
2002, 21, 3471–3476; c) T. Rüffer, C. Bruhn, E. Rusanov, K.
Nordhoff, D. Steinborn, Z. Anorg. Allg. Chem. 2002, 628, 421–
427.
[5] a) O. Kluge, S. Gerber, H. Krautscheid, Z. Anorg. Allg. Chem.
2011, 637, 1909–1921; b) Treatment of InMe3 with PhSeSiMe3
in MeCN results in the formation of TMS and (Me2InSePh)n.
However, no conclusion can be made by comparing the total
energies (obtained by DFT calculations) of the reactants, the
adduct, and the hypothetical products, as the reactants and the
products differ little in energy (In–C and Si–E bond versus In–
E and Si–C bond), and the sign depends on the computational
details (functional, basis sets) and corrections (ZPVE, BSSE).
Despite this, the adduct contains one additional bond (fourfold
coordinated In atom) and is therefore more stable than the
reactants and the products.
[12]
[13]
I. G. Dance, Polyhedron 1986, 5, 1037–1104.
O. Kluge, K. Grummt, R. Biedermann, H. Krautscheid, Inorg.
Chem. 2011, 50, 4742–4752.
[14]
[15]
P. G. Eller, G. J. Kubas, J. Am. Chem. Soc. 1977, 99, 4346–4351.
The relatively large overestimation (ca. 10 pm) of the In–E
bond lengths is presumably due to a combination of dispersion
interactions usually neglected by DFT and a bond shortening
in the solid state, caused by the polar environment. For the
latter, see: M. Bühl, T. Steinke, P. v. R. Schleyer, R. Boese, An-
gew. Chem. 1991, 103, 1179–1181; Angew. Chem. Int. Ed. Engl.
1991, 30, 1160.
S. Berger, S. Braun, H.-O. Kalinowski, NMR-Spektroskopie von
Nichtmetallen, vol. 3, 31P-NMR-Spektroskopie, Thieme, Stutt-
gart, Germany, 1993, p. 88; U. Siegert, H. Hahn, H. Lang,
Inorg. Chim. Acta 2010, 363, 944–948.
V. V. Shatunov, A. A. Korlyukov, A. V. Lebedev, V. D. Shelud-
yakov, B. I. Kozyrkin, V. Yu. Orlov, J. Organomet. Chem. 2011,
696, 2238–2251.
D. A. Edwards, R. Richards, J. Chem. Soc., Dalton Trans. 1973,
2463.
[16]
[17]
[18]
[19]
[20]
G. Brauer (Ed.), Handbuch der Präparativen Anorganischen
Chemie, Enke Verlag, Stuttgart, 1978, p. 864f.
A. Altomare, G. Cascarano, C. Giacovazzo, A. Gualardi, J.
Appl. Crystallogr. 1993, 26, 343.
[21]
[22]
G. M. Sheldrick, Acta Crystallogr., Sect. A 2008, 64, 112.
a) A. D. Becke, J. Chem. Phys. 1993, 98, 5648; b) C. Lee, W.
Yang, R. G. Parr, Phys. Rev. B 1988, 37, 785; c) S. J. Vosko, L.
Wilk, M. Nusair, Can. J. Phys. 1980, 58, 1200.
[23]
[6] J. L. Atwood, S. K. Seale, J. Organomet. Chem. 1976, 114, 107–
M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. Scuseria,
M. A. Robb, J. R. Cheeseman, J. A. Montgomery Jr., T.
Vreven, K. N. Kudin, J. C. Burant, J. M. Millam, S. S. Iyengar,
J. Tomasi, V. Barone, B. Mennucci, M. Cossi, G. Scalmani, N.
Rega, G. A. Petersson, H. Nakatsuji, M. Hada, M. Ehara, K.
Toyota, R. Fukuda, J. Hasegawa, M. Ishida, T. Nakajima, Y.
Honda, O. Kitao, H. Nakai, M. Klene, X. Li, J. E. Knox, H. P.
Hratchian, J. B. Cross, V. Bakken, C. Adamo, J. Jaramillo, R.
Gomperts, R. E. Stratmann, O. Yazyev, A. J. Austin, R.
Cammi, C. Pomelli, J. W. Ochterski, P. Y. Ayala, K. Morok-
uma, G. A. Voth, P. Salvador, J. J. Dannenberg, V. G. Zakrzew-
ski, S. Dapprich, A. D. Daniels, M. C. Strain, O. Farkas, D. K.
118.
[7] a) O. Kluge, H. Krautscheid, Inorg. Chem. 2012, 51, 6655–
6666; b) O. Kluge, D. Friedrich, G. Wagner, H. Krautscheid,
Dalton Trans. 2012, 41, 8635–8642.
[8] a) S. Dehnen, A. Eichhöfer, D. Fenske, Eur. J. Inorg. Chem.
2002, 279–317; b) M. W. DeGroot, J. F. Corrigan, Z. Anorg.
Allg. Chem. 2006, 632, 19–29.
[9] a) A. Eichhöfer, D. Fenske, J. Chem. Soc., Dalton Trans. 2000,
941–944; b) D. T. T. Tran, L. M. C. Beltran, C. M. Kowalchuk,
N. R. Trefiak, N. J. Taylor, J. F. Corrigan, Inorg. Chem. 2002,
41, 5693–5698; c) J. Olkowska-Oetzel, D. Fenske, P. Scheer, A.
Eur. J. Inorg. Chem. 0000, 0–0
4
© 0000 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

Job/Unit: I30768
/KAP1
Date: 20-08-13 17:25:30
Pages: 6
www.eurjic.org
SHORT COMMUNICATION
Malick, A. D. Rabuck, K. Raghavachari, J. B. Foresman, J. V.
Ortiz, Q. Cui, A. G. Baboul, S. Clifford, J. Cioslowski, B. B.
Stefanov, G. Liu, A. Liashenko, P. Piskorz, I. Komaromi, R. L.
Martin, D. J. Fox, T. Keith, M. A. Al-Laham, C. Y. Peng, A.
Nanayakkara, M. Challacombe, P. M. W. Gill, B. Johnson, W.
Chen, M. W. Wong, C. Gonzalez, J. A. Pople, Gaussian 03, rev.
D.02, Gaussian, Inc., Wallingford, CT, 2004.
1980, 72, 650; d) A. J. H. Wachters, J. Chem. Phys. 1970, 52,
1033; e) P. J. Hay, J. Chem. Phys. 1977, 66, 4377; f) K. Raghava-
chari, G. W. Trucks, J. Chem. Phys. 1989, 91, 1062; g) R. C.
Binning Jr., L. A. Curtiss, J. Comput. Chem. 1990, 11, 1206; h)
L. A. Curtiss, M. P. McGrath, J.-P. Blaudeau, N. E. Davis,
R. C. Binning Jr., L. Radom, J. Chem. Phys. 1995, 103, 6104;
i) P. J. Hay, W. R. Wadt, J. Chem. Phys. 1985, 82, 270; j) W. R.
Wadt, P. J. Hay, J. Chem. Phys. 1985, 82, 284; k) P. J. Hay, W. R.
Wadt, J. Chem. Phys. 1985, 82, 299.
[24] a) W. J. Hehre, L. Radom, P. v. R. Schleyer, J. Pople, Ab initio
Molecular Orbital Theory, Wiley, New York, 1986; b) A. D.
McLean, G. S. Chandler, J. Chem. Phys. 1980, 72, 5639; c) R.
Krishnan, J. S. Binkley, R. Seeger, J. A. Pople, J. Chem. Phys.
Received: June 19, 2013
Published Online: ᭿
Eur. J. Inorg. Chem. 0000, 0–0
5
© 0000 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

Job/Unit: I30768
/KAP1
Date: 20-08-13 17:25:30
Pages: 6
www.eurjic.org
SHORT COMMUNICATION
Lewis Acid–Base Adducts
R. Biedermann, O. Kluge, D. Fuhrmann,
H. Krautscheid* ................................ 1–6
Lewis acid–base adducts of trimethyl-
indium and phosphane-stabilized copper(I)
(trimethylsilyl)chalcogenolates were syn-
thesized and characterized by X-ray crystal
structure determination. They are very un-
stable under atmospheric conditions and
decompose at ambient temperatures. DFT
calculations reveal that the unusual planar
coordination of the chalcogen atoms is due
to steric crowding.
SynthesisandCrystalStructuresof[(iPr3P)2-
Cu(μ-ESiMe3)(InMe3)] (E = S, Se): Lewis
Acid–Base Adducts with Chalcogen Atoms
in Planar Coordination
Keywords: Lewis acids / Lewis bases / Chal-
cogens / Density functional calculations /
Structure elucidation
Eur. J. Inorg. Chem. 0000, 0–0
6
© 0000 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim