Crystal structure of 2,2,3,3-tetra­methyl-1,1,1,4,4,4-hexa­phenyl­tetra­germane

Zaitsev, K.V.; Karlov, S.S.; Zaitseva, G.S.; Alizade, A.; Slovokhotov, Y.L.

doi:10.1107/S160053681402501X

organic compounds

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ISSN: 2056-9890

Volume 70| Part 12| December 2014| Pages o1273-o1274

doi:10.1107/S160053681402501X

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Crystal structure of 2,2,3,3-tetramethyl-1,1,1,4,4,4-hexaphenyltetragermane

Kirill V. Zaitsev,^a Sergey S. Karlov,^a Galina S. Zaitseva,^a Ali Alizade ^b and Yuri L. Slovokhotov ^a ^*

^aDepartment of Chemistry, Moscow State University, 119991 Moscow, Russian Federation, and ^bMoscow State University (Baku Branch), AZ1144 Universitet st. 1, Khojasan, Binagadi, Baku, Azerbaijan
^*Correspondence e-mail: yurislovo@yandex.ru

Edited by M. Weil, Vienna University of Technology, Austria (Received 30 October 2014; accepted 14 November 2014; online 21 November 2014)

The molecule of the title compound, C₄₀H₄₂Ge₄, lies with its central Ge—Ge bond on an inversion centre giving rise to a zigzag backbone of four tetrahedrally coordinated Ge atoms. The symmetrically independent Ge—Ge bonds are slightly shorter than in other organotetragermanes whereas the Ge—C_Ph (Ph = phenyl) and Ge—C_Me (Me = methyl) distances have their usual values. In the crystal, (010) layers of Ph₆Me₄Ge₄ molecules with a parallel orientation of the Ge₄ backbone exist, held together by van der Waals forces only. Main bond lengths in organo-substituted oligogermanes are compared.

Keywords: crystal structure; organotetragermane; zigzag backbone; layered structure.

CCDC reference: 1034201

1. Related literature

A search for `organic electronics' materials in systems of conjugated C—C bonds (Kobayashi et al., 2011 ) was recently extended to organometallic molecules containing chains of atoms such as Ge, Si, or Sn (Marschner & Hlina, 2013 ). The established routines used to obtain oligogermanes via hydrogermolysis or the reaction of germyllithium reagents with germanium halogenides (Amadoruge & Weinert, 2008 ) may give rise to unexpected by-products due to side reactions. As a part of our studies of the chemistry of oligogermanium compounds (Zaitsev et al., 2012 , 2013 , 2014 ), the title compound was obtained as a by-product. For related crystal structures of organotetragermanes, see: Roller et al. (1986 ); Dräger & Simon (1986 ); Wagner et al. (2009 ); Amadoruge et al. (2010 ).

2. Experimental

2.1. Crystal data

C₄₀H₄₂Ge₄
M_r = 813.10
Monoclinic, P 2₁ /c
a = 9.6402 (5) Å
b = 13.6386 (6) Å
c = 14.0503 (7) Å
β = 104.560 (1)°
V = 1787.99 (15) Å³
Z = 2
Mo Kα radiation
μ = 3.36 mm⁻¹
T = 120 K
0.55 × 0.53 × 0.11 mm

2.2. Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2008 ) T_min = 0.391, T_max = 0.701
22283 measured reflections
5210 independent reflections
4222 reflections with I > 2σ(I)
R_int = 0.039

2.3. Refinement

R[F² > 2σ(F²)] = 0.030
wR(F²) = 0.066
S = 1.05
5210 reflections
202 parameters
H-atom parameters constrained
Δρ_max = 0.62 e Å⁻³
Δρ_min = −0.39 e Å⁻³

Table 1
Main bond lengths (Å) in organo-substituted oligogermanes

Me is CH₃, Ms is Me₃Si and Tol is p-C₆H₄Me.

Compound	Ge—Ge_periph	Ge—Ge_central	Ge—C_Ph	Ge—C_Me
Ph₃GeMe₂GeGeMe₂GePh₃^a	2.4361 (3)	2.4276 (4)	1.961	1.965
Ms₃GeMe₂GeGeMe₂GeMs₃^b	2.441	2.442	–	1.967
Tol₃GeGePh₂GePh₂GeTol₃^c	2.443	2.457	1.973	–
Ph₃GeGePh₂GePh₂GePh₃^d	2.464	2.461	1.969	–
Ph₃GeGeMe₂GePh₃^e	2.429	–	1.957	1.944
References: (a) This work; (b) Wagner et al. (2009); (c) Amadoruge et al. (2010); (d) Roller et al. (1986); (e) Dräger & Simon (1986).

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information

CCDC reference: 1034201

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053681402501X/wm5086sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681402501X/wm5086Isup2.hkl

Supporting information file. DOI: 10.1107/S160053681402501X/wm5086Isup3.cml

checkCIF report

Related literature top

A search for `organic electronics' materials in systems of conjugated C—C bonds (Kobayashi et al., 2011) was recently extended to organometallic molecules containing chains of atoms such as Ge, Si, or Sn (Marschner & Hlina, 2013). The established routines used to obtain oligogermanes via hydrogermolysis or the reaction of germyllithium reagents with germanium halogenides (Amadoruge & Weinert, 2008) may give rise to unexpected by-products due to side reactions. As a part of our studies of the chemistry of oligogermanium compounds (Zaitsev et al., 2012, 2013, 2014), the title compound was obtained as a by-product. For related crystal structures of organotetragermanes, see: Roller et al. (1986); Dräger & Simon (1986); Wagner et al. (2009); Amadoruge et al. (2010).

Experimental top

The title compound was obtained in trace amounts from the reaction of two equivalents of Ph₃GeLi (generated in situ from Ph₃GeH and n-BuLi at room temperature in Et₂O) with Me₂GeCl₂ in diethyl ether. The main compound isolated from the mother liquor is the known trigermane Ph₃GeGeMe₂GePh₃ (Dräger & Simon, 1986). Solvent-free crystals of the title compound suitable for X-Ray analysis were recrystallized from toluene at room temperature.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

A view of the title molecule showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. Hydrogen atoms are omitted for clarity. [Symmetry operator (A) -x +1, -y+1, -z+1.]

2,2,3,3-Tetramethyl-1,1,1,4,4,4-hexaphenyltetragermane top

Crystal data top

C₄₀H₄₂Ge₄	F(000) = 820
M_r = 813.10	D_x = 1.510 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 7722 reflections
a = 9.6402 (5) Å	θ = 2.2–32.5°
b = 13.6386 (6) Å	µ = 3.36 mm⁻¹
c = 14.0503 (7) Å	T = 120 K
β = 104.560 (1)°	Prism, colourless
V = 1787.99 (15) Å³	0.55 × 0.53 × 0.11 mm
Z = 2

Data collection top

Bruker APEXII CCD diffractometer	5210 independent reflections
Radiation source: fine-focus sealed tube	4222 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.039
ϕ and ω scans	θ_max = 30.0°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −13→13
T_min = 0.391, T_max = 0.701	k = −19→19
22283 measured reflections	l = −19→19

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.030	H-atom parameters constrained
wR(F²) = 0.066	w = 1/[σ²(F_o²) + (0.0262P)² + 0.6663P] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max = 0.001
5210 reflections	Δρ_max = 0.62 e Å⁻³
202 parameters	Δρ_min = −0.39 e Å⁻³
0 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0062 (3)

Crystal data top

C₄₀H₄₂Ge₄	V = 1787.99 (15) Å³
M_r = 813.10	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 9.6402 (5) Å	µ = 3.36 mm⁻¹
b = 13.6386 (6) Å	T = 120 K
c = 14.0503 (7) Å	0.55 × 0.53 × 0.11 mm
β = 104.560 (1)°

Data collection top

Bruker APEXII CCD diffractometer	5210 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2008)	4222 reflections with I > 2σ(I)
T_min = 0.391, T_max = 0.701	R_int = 0.039
22283 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.030	0 restraints
wR(F²) = 0.066	H-atom parameters constrained
S = 1.05	Δρ_max = 0.62 e Å⁻³
5210 reflections	Δρ_min = −0.39 e Å⁻³
202 parameters

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Ge1	0.44925 (2)	0.553177 (15)	0.551768 (15)	0.01582 (6)
Ge2	0.35670 (2)	0.459956 (15)	0.670324 (16)	0.01586 (6)
C1	0.5900 (3)	0.65022 (16)	0.61880 (17)	0.0266 (5)
H1A	0.6311	0.6837	0.5705	0.040*
H1B	0.6665	0.6172	0.6675	0.040*
H1C	0.5430	0.6983	0.6520	0.040*
C2	0.2832 (2)	0.62288 (17)	0.47117 (16)	0.0264 (5)
H2A	0.3153	0.6698	0.4284	0.040*
H2B	0.2340	0.6580	0.5140	0.040*
H2C	0.2171	0.5757	0.4308	0.040*
C3	0.2686 (2)	0.33907 (14)	0.60806 (14)	0.0175 (4)
C4	0.1389 (2)	0.34120 (15)	0.53599 (16)	0.0224 (4)
H4A	0.0886	0.4014	0.5208	0.027*
C5	0.0824 (2)	0.25622 (17)	0.48630 (17)	0.0264 (5)
H5A	−0.0056	0.2588	0.4372	0.032*
C6	0.1544 (2)	0.16757 (16)	0.50815 (17)	0.0256 (5)
H6A	0.1155	0.1097	0.4742	0.031*
C7	0.2829 (2)	0.16369 (15)	0.57958 (16)	0.0236 (4)
H7A	0.3320	0.1031	0.5949	0.028*
C8	0.3399 (2)	0.24892 (15)	0.62893 (15)	0.0201 (4)
H8A	0.4285	0.2459	0.6775	0.024*
C9	0.5064 (2)	0.42690 (14)	0.78825 (15)	0.0170 (4)
C10	0.4757 (2)	0.41586 (16)	0.87949 (16)	0.0227 (4)
H10A	0.3798	0.4234	0.8844	0.027*
C11	0.5827 (3)	0.39404 (16)	0.96343 (16)	0.0255 (5)
H11A	0.5593	0.3861	1.0247	0.031*
C12	0.7234 (2)	0.38385 (15)	0.95799 (16)	0.0249 (5)
H12A	0.7968	0.3701	1.0155	0.030*
C13	0.7560 (2)	0.39384 (16)	0.86836 (16)	0.0244 (5)
H13A	0.8521	0.3859	0.8641	0.029*
C14	0.6489 (2)	0.41554 (15)	0.78413 (16)	0.0204 (4)
H14A	0.6730	0.4227	0.7230	0.024*
C15	0.2120 (2)	0.53782 (15)	0.71306 (15)	0.0182 (4)
C16	0.2365 (2)	0.63689 (15)	0.73511 (16)	0.0222 (4)
H16A	0.3224	0.6664	0.7276	0.027*
C17	0.1380 (2)	0.69347 (16)	0.76790 (16)	0.0245 (5)
H17A	0.1577	0.7606	0.7835	0.029*
C18	0.0110 (2)	0.65232 (17)	0.77794 (16)	0.0259 (5)
H18A	−0.0574	0.6911	0.7992	0.031*
C19	−0.0148 (3)	0.55397 (17)	0.7565 (2)	0.0317 (5)
H19A	−0.1011	0.5250	0.7639	0.038*
C20	0.0841 (2)	0.49707 (16)	0.72433 (18)	0.0266 (5)
H20A	0.0645	0.4297	0.7098	0.032*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ge1	0.01786 (11)	0.01507 (10)	0.01456 (11)	0.00087 (7)	0.00413 (8)	0.00019 (8)
Ge2	0.01524 (11)	0.01695 (11)	0.01510 (11)	−0.00037 (8)	0.00329 (8)	0.00050 (8)
C1	0.0321 (13)	0.0246 (11)	0.0233 (11)	−0.0078 (9)	0.0076 (9)	−0.0030 (9)
C2	0.0299 (12)	0.0282 (11)	0.0200 (11)	0.0107 (9)	0.0043 (9)	0.0031 (9)
C3	0.0166 (10)	0.0214 (10)	0.0148 (9)	−0.0012 (7)	0.0046 (8)	0.0004 (7)
C4	0.0214 (11)	0.0225 (10)	0.0217 (11)	0.0004 (8)	0.0022 (8)	0.0021 (8)
C5	0.0223 (11)	0.0319 (12)	0.0225 (11)	−0.0049 (9)	0.0011 (9)	−0.0019 (9)
C6	0.0258 (12)	0.0261 (11)	0.0259 (12)	−0.0071 (9)	0.0084 (9)	−0.0065 (9)
C7	0.0257 (11)	0.0202 (10)	0.0261 (12)	0.0005 (8)	0.0086 (9)	0.0013 (8)
C8	0.0188 (10)	0.0232 (10)	0.0182 (10)	−0.0003 (8)	0.0045 (8)	0.0028 (8)
C9	0.0187 (10)	0.0144 (9)	0.0169 (10)	−0.0015 (7)	0.0027 (8)	0.0004 (7)
C10	0.0221 (11)	0.0240 (10)	0.0226 (11)	−0.0007 (8)	0.0068 (9)	0.0019 (8)
C11	0.0320 (12)	0.0276 (11)	0.0166 (10)	0.0007 (9)	0.0056 (9)	0.0048 (8)
C12	0.0293 (12)	0.0216 (10)	0.0198 (11)	0.0020 (8)	−0.0011 (9)	0.0023 (8)
C13	0.0209 (11)	0.0254 (11)	0.0258 (12)	0.0037 (8)	0.0035 (9)	0.0027 (9)
C14	0.0203 (10)	0.0236 (10)	0.0179 (10)	0.0026 (8)	0.0060 (8)	0.0011 (8)
C15	0.0172 (9)	0.0225 (10)	0.0146 (9)	0.0008 (8)	0.0031 (7)	0.0026 (8)
C16	0.0193 (10)	0.0243 (10)	0.0227 (11)	−0.0040 (8)	0.0051 (8)	−0.0038 (8)
C17	0.0266 (12)	0.0243 (10)	0.0219 (11)	0.0004 (9)	0.0048 (9)	−0.0047 (8)
C18	0.0255 (12)	0.0315 (12)	0.0225 (11)	0.0071 (9)	0.0096 (9)	0.0010 (9)
C19	0.0214 (11)	0.0352 (13)	0.0427 (15)	−0.0027 (9)	0.0162 (10)	0.0027 (11)
C20	0.0243 (12)	0.0235 (11)	0.0345 (13)	−0.0027 (9)	0.0117 (10)	0.0006 (9)

Geometric parameters (Å, º) top

Ge1—C2	1.959 (2)	C8—H8A	0.9500
Ge1—C1	1.959 (2)	C9—C10	1.394 (3)
Ge1—Ge1ⁱ	2.4276 (4)	C9—C14	1.398 (3)
Ge1—Ge2	2.4361 (3)	C10—C11	1.390 (3)
Ge2—C9	1.957 (2)	C10—H10A	0.9500
Ge2—C3	1.957 (2)	C11—C12	1.384 (3)
Ge2—C15	1.963 (2)	C11—H11A	0.9500
C1—H1A	0.9800	C12—C13	1.379 (3)
C1—H1B	0.9800	C12—H12A	0.9500
C1—H1C	0.9800	C13—C14	1.393 (3)
C2—H2A	0.9800	C13—H13A	0.9500
C2—H2B	0.9800	C14—H14A	0.9500
C2—H2C	0.9800	C15—C16	1.393 (3)
C3—C4	1.398 (3)	C15—C20	1.397 (3)
C3—C8	1.403 (3)	C16—C17	1.390 (3)
C4—C5	1.391 (3)	C16—H16A	0.9500
C4—H4A	0.9500	C17—C18	1.386 (3)
C5—C6	1.389 (3)	C17—H17A	0.9500
C5—H5A	0.9500	C18—C19	1.383 (3)
C6—C7	1.386 (3)	C18—H18A	0.9500
C6—H6A	0.9500	C19—C20	1.391 (3)
C7—C8	1.394 (3)	C19—H19A	0.9500
C7—H7A	0.9500	C20—H20A	0.9500

C2—Ge1—C1	108.47 (10)	C7—C8—C3	121.03 (19)
C2—Ge1—Ge1ⁱ	109.73 (7)	C7—C8—H8A	119.5
C1—Ge1—Ge1ⁱ	110.91 (7)	C3—C8—H8A	119.5
C2—Ge1—Ge2	105.19 (7)	C10—C9—C14	117.63 (19)
C1—Ge1—Ge2	110.63 (7)	C10—C9—Ge2	121.46 (16)
Ge1ⁱ—Ge1—Ge2	111.715 (14)	C14—C9—Ge2	120.90 (15)
C9—Ge2—C3	109.21 (8)	C11—C10—C9	121.3 (2)
C9—Ge2—C15	107.16 (9)	C11—C10—H10A	119.3
C3—Ge2—C15	109.31 (8)	C9—C10—H10A	119.3
C9—Ge2—Ge1	112.36 (6)	C12—C11—C10	120.2 (2)
C3—Ge2—Ge1	109.04 (6)	C12—C11—H11A	119.9
C15—Ge2—Ge1	109.71 (6)	C10—C11—H11A	119.9
Ge1—C1—H1A	109.5	C13—C12—C11	119.5 (2)
Ge1—C1—H1B	109.5	C13—C12—H12A	120.3
H1A—C1—H1B	109.5	C11—C12—H12A	120.3
Ge1—C1—H1C	109.5	C12—C13—C14	120.4 (2)
H1A—C1—H1C	109.5	C12—C13—H13A	119.8
H1B—C1—H1C	109.5	C14—C13—H13A	119.8
Ge1—C2—H2A	109.5	C13—C14—C9	121.0 (2)
Ge1—C2—H2B	109.5	C13—C14—H14A	119.5
H2A—C2—H2B	109.5	C9—C14—H14A	119.5
Ge1—C2—H2C	109.5	C16—C15—C20	117.75 (19)
H2A—C2—H2C	109.5	C16—C15—Ge2	119.92 (15)
H2B—C2—H2C	109.5	C20—C15—Ge2	122.31 (16)
C4—C3—C8	118.14 (19)	C17—C16—C15	121.4 (2)
C4—C3—Ge2	120.99 (15)	C17—C16—H16A	119.3
C8—C3—Ge2	120.67 (15)	C15—C16—H16A	119.3
C5—C4—C3	120.8 (2)	C18—C17—C16	120.3 (2)
C5—C4—H4A	119.6	C18—C17—H17A	119.9
C3—C4—H4A	119.6	C16—C17—H17A	119.9
C6—C5—C4	120.2 (2)	C19—C18—C17	119.1 (2)
C6—C5—H5A	119.9	C19—C18—H18A	120.5
C4—C5—H5A	119.9	C17—C18—H18A	120.5
C7—C6—C5	119.9 (2)	C18—C19—C20	120.7 (2)
C7—C6—H6A	120.0	C18—C19—H19A	119.6
C5—C6—H6A	120.0	C20—C19—H19A	119.6
C6—C7—C8	119.9 (2)	C19—C20—C15	120.8 (2)
C6—C7—H7A	120.1	C19—C20—H20A	119.6
C8—C7—H7A	120.1	C15—C20—H20A	119.6

Symmetry code: (i) −x+1, −y+1, −z+1.

Main bond lengths (Å) in organo-substituted oligogermanes top

Me is CH₃, Ms is Me₃Si and Tol is p-C₆H₄Me.

Compound	Ge—Ge_periph	Ge—Ge_central	Ge—C_Ph	Ge—C_Me
Ph₃GeMe₂GeGeMe₂GePh₃^a	2.4361 (3)	2.4276 (4)	1.961	1.965
Ms₃GeMe₂GeGeMe₂GeMs₃^b	2.441	2.442	–	1.967
Tol₃GeGePh₂GePh₂GeTol₃^c	2.443	2.457	1.973	–
Ph₃GeGePh₂GePh₂GePh₃^d	2.464	2.461	1.969	–
Ph₃GeGeMe₂GePh₃^e	2.429	–	1.957	1.944

References: (a) This work; (b) Wagner et al. (2009); (c) Amadoruge et al. (2010); (d) Roller et al. (1986); (e) Dräger & Simon (1986).

Acknowledgements

This work was partially supported by a grant from the President of the Russian Federation to support the research of young Russian scientists and PhDs (MK-1790.2014.3)

References

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