Bis(bicyclo­[2.2.1]hept-5-ene-2-carboxyl­ato)-1κ² O,O′;4κ² O,O′-di-μ₂-chlorido-1:2κ² Cl;3:4κ² Cl-octa­methyl-1κ² C,2κ² C,3κ² C,4κ² C-di-μ₃-oxido-1:2:3κ³ O;2:3:4κ³ O-tetra­tin(IV)

Abstract

In the title compound, [Sn₄(CH₃)₈(C₈H₉O₂)₂Cl₂O₂], the tetra­nuclear complex mol­ecule has crystallographically imposed inversion symmetry. The coordination polyhedron about the two central Sn atoms is distorted trigonal–bipyramidal, whilst the two peripheral metal atoms bonded to the carboxyl­ate groups have a distorted octa­hedral coordination geometry. In the crystal, mol­ecules are connected by long Sn⋯O contacts [3.139 (11) Å], forming chains along [011].

Related literature

For the biological activity of organotin compounds, see: Dubey & Roy (2003 ▶). For a related structure, see: Li et al. (2006 ▶).

Experimental

Crystal data

• [Sn₄(CH₃)₈(C₈H₉O₂)₂Cl₂O₂]

• M _r = 972.24

• Triclinic,

• a = 9.3685 (12) Å

• b = 9.8651 (13) Å

• c = 9.9103 (15) Å

• α = 109.779 (2)°

• β = 96.340 (1)°

• γ = 97.204 (1)°

• V = 843.5 (2) ų

• Z = 1

• Mo Kα radiation

• μ = 3.12 mm⁻¹

• T = 298 K

• 0.13 × 0.11 × 0.05 mm

Data collection

• Siemens SMART CCD area-detector diffractometer

• Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T _min = 0.687, T _max = 0.860

• 4366 measured reflections

• 2915 independent reflections

• 1818 reflections with I > 2σ(I)

• R _int = 0.024

Refinement

• R[F ² > 2σ(F ²)] = 0.047

• wR(F ²) = 0.130

• S = 1.02

• 2915 reflections

• 163 parameters

• H-atom parameters constrained

• Δρ_max = 0.86 e Å⁻³

• Δρ_min = −0.64 e Å⁻³

Data collection: SMART (Siemens, 1996 ▶); cell refinement: SAINT (Siemens, 1996 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXTL.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Comment

In recent years, organotin compounds have attracted more and more attention due to their wide range of industrial applications and biological activities (Dubey & Roy, 2003). As a part of our ongoing investigations in this field, we have synthesized the title compound and present its crystal structure here.

The tetranuclear complex molecule of the title compound (Fig. 1) has crystallographically imposed inversion symmetry. The tin atoms have two different coordination modes, one atom (Sn2) is coordinated in a distorted trigonal-bipyramidal geometry by one µ₃oxo oxygen atom and two methyl groups forming the equatorial plane, and by an µ₃oxo oxygen atom and the chloride anion at the apices; the other tin metal (Sn1) has a distorted octahedral coordination geometry, with three O atoms and one Cl atom in equatorial positions and the axial position occupied by two methyl groups. The Sn—O bond distances involving the carboxylate group (Sn1—O2 = 2.115 (8) Å; Sn1—O3 = 2.699 (9) Å) are comparable to those found in a related organotin carboxylate (Li et al., 2006). The shortest Sn···Sn separation within the Sn₄ core is 3.2898 (10) Å. In the crystal structure, complex molecules are connected by long Sn···O interaction (Sn1···O3ⁱ = 3.139 (11) Å; symmetry code: (i) 1-x, -y, 1-z) into one-dimensional chains parallel to the [011] direction (Fig. 2).

Experimental

The reaction was carried out under a nitrogen atmosphere. Bicyclo[2.2.1]heptane-2-carboxylic acid (1 mmol) and sodium ethoxide (1 mmol) were added to a stirred solution of benzene (30 ml) in a Schlenk flask After stirring the solution for 30 min, dimethyltin dichloride (2 mmol) was added and the reaction mixture was stirred for 12 h at room temperature. The resulting clear solution was evaporated under vacuum. The product was crystallized from a solution of diethyl ether to yield colourless crystals of the title compound suitable for X-ray analysis (yield: 76%). Anal. Calcd (%) for C₂₄H₄₂Cl₂O₆Sn₄ (Mr = 972.33): C, 29.65; H, 4.35. Found (%): C, 29.47; H, 4.52.

Refinement

The H atoms were positioned geometrically, with C—H = 0.93–0.98 Å, and refined as riding on their parent atoms, with U_iso(H) = 1.2 U_eq(C) or 1.5 U_eq(C) for the methyl groups.

Figures

Fig. 1.

The molecular structure of the title compound, showing 50% probability displacement ellipsoids. H atoms have been omitted for clarity. Symmetry code: (A) 1-x, 1-y, 2-z.

Fig. 2.

View of the one-dimensional chain structure in the title compound.

Crystal data

[Sn4(CH3)8(C8H9O2)2Cl2O2]	Z = 1
Mr = 972.24	F(000) = 468
Triclinic, P1	Dx = 1.914 Mg m−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 9.3685 (12) Å	Cell parameters from 1509 reflections
b = 9.8651 (13) Å	θ = 2.2–25.2°
c = 9.9103 (15) Å	µ = 3.12 mm−1
α = 109.779 (2)°	T = 298 K
β = 96.340 (1)°	Block, colourless
γ = 97.204 (1)°	0.13 × 0.11 × 0.05 mm
V = 843.5 (2) Å3

Data collection

Siemens SMART CCD area-detector diffractometer	2915 independent reflections
Radiation source: fine-focus sealed tube	1818 reflections with I > 2σ(I)
graphite	Rint = 0.024
φ and ω scans	θmax = 25.0°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −6→11
Tmin = 0.687, Tmax = 0.860	k = −11→10
4366 measured reflections	l = −11→11

Refinement

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.130	H-atom parameters constrained
S = 1.02	w = 1/[σ2(Fo2) + (0.0634P)2] where P = (Fo2 + 2Fc2)/3
2915 reflections	(Δ/σ)max = 0.001
163 parameters	Δρmax = 0.86 e Å−3
0 restraints	Δρmin = −0.64 e Å−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Sn1	0.52583 (8)	0.20738 (8)	0.72575 (8)	0.0642 (3)
Sn2	0.34860 (7)	0.52430 (7)	0.91708 (7)	0.0541 (2)
Cl1	0.2281 (3)	0.7487 (4)	1.0584 (3)	0.0893 (9)
O1	0.5103 (6)	0.3891 (6)	0.8952 (6)	0.0567 (16)
O2	0.3315 (9)	0.2563 (10)	0.6371 (9)	0.104 (3)
O3	0.3517 (12)	0.0621 (12)	0.4673 (11)	0.123 (3)
C1	0.2708 (19)	0.160 (2)	0.5170 (19)	0.126 (6)
C2	0.114 (2)	0.312 (2)	0.436 (2)	0.147 (7)
H2	0.1241	0.4026	0.5205	0.177*
C3	0.1132 (19)	0.168 (2)	0.4573 (18)	0.137 (6)
H3	0.0508	0.1632	0.5294	0.164*
C4	0.042 (2)	0.057 (2)	0.3123 (19)	0.152 (7)
H4A	0.1041	−0.0144	0.2773	0.183*
H4B	−0.0502	0.0065	0.3211	0.183*
C5	0.017 (2)	0.135 (2)	0.2080 (19)	0.139 (6)
H5	−0.0452	0.0854	0.1128	0.166*
C6	0.183 (2)	0.175 (2)	0.223 (2)	0.156 (7)
H6	0.2425	0.1242	0.1621	0.187*
C7	0.226 (2)	0.295 (2)	0.337 (2)	0.153 (7)
H7	0.3122	0.3604	0.3543	0.183*
C8	−0.0092 (18)	0.277 (2)	0.3130 (18)	0.140 (6)
H8A	−0.0047	0.3524	0.2702	0.168*
H8B	−0.1029	0.2657	0.3446	0.168*
C9	0.6728 (14)	0.2796 (14)	0.6114 (13)	0.101 (4)
H9A	0.7045	0.3833	0.6575	0.152*
H9B	0.6262	0.2576	0.5134	0.152*
H9C	0.7556	0.2311	0.6106	0.152*
C10	0.4421 (14)	0.0339 (13)	0.7839 (13)	0.095 (4)
H10A	0.4365	0.0689	0.8857	0.142*
H10B	0.5048	−0.0379	0.7639	0.142*
H10C	0.3464	−0.0094	0.7289	0.142*
C11	0.4013 (13)	0.6224 (13)	0.7674 (12)	0.086 (3)
H11A	0.3294	0.6805	0.7552	0.129*
H11B	0.4031	0.5479	0.6756	0.129*
H11C	0.4954	0.6837	0.8028	0.129*
C12	0.1694 (12)	0.3767 (14)	0.9197 (13)	0.098 (4)
H12A	0.1857	0.2786	0.8743	0.147*
H12B	0.0834	0.3910	0.8676	0.147*
H12C	0.1567	0.3928	1.0184	0.147*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Sn1	0.0789 (5)	0.0509 (5)	0.0573 (5)	0.0212 (4)	0.0060 (4)	0.0105 (4)
Sn2	0.0483 (4)	0.0559 (5)	0.0558 (4)	0.0153 (3)	−0.0009 (3)	0.0177 (3)
Cl1	0.0721 (18)	0.088 (2)	0.092 (2)	0.0425 (15)	−0.0049 (15)	0.0080 (17)
O1	0.057 (4)	0.052 (4)	0.056 (4)	0.028 (3)	−0.001 (3)	0.009 (3)
O2	0.113 (7)	0.093 (7)	0.090 (6)	0.043 (5)	−0.023 (5)	0.013 (5)
O3	0.142 (9)	0.113 (9)	0.091 (7)	0.039 (7)	−0.028 (6)	0.016 (6)
C1	0.132 (14)	0.121 (14)	0.103 (12)	0.041 (11)	−0.031 (10)	0.023 (11)
C2	0.154 (17)	0.134 (17)	0.121 (15)	0.047 (13)	−0.017 (13)	0.009 (12)
C3	0.163 (16)	0.124 (15)	0.108 (13)	0.021 (12)	−0.021 (11)	0.036 (12)
C4	0.157 (16)	0.137 (16)	0.131 (15)	0.024 (12)	−0.027 (12)	0.022 (14)
C5	0.146 (16)	0.137 (16)	0.108 (13)	0.033 (12)	−0.038 (11)	0.028 (12)
C6	0.147 (17)	0.154 (18)	0.122 (15)	0.036 (13)	−0.005 (12)	−0.002 (13)
C7	0.150 (17)	0.141 (18)	0.132 (16)	0.020 (13)	−0.001 (14)	0.012 (14)
C8	0.141 (14)	0.138 (16)	0.124 (14)	0.065 (11)	−0.025 (11)	0.025 (12)
C9	0.125 (11)	0.091 (10)	0.084 (9)	0.025 (8)	0.029 (8)	0.019 (8)
C10	0.109 (10)	0.075 (9)	0.093 (9)	0.009 (7)	0.003 (7)	0.028 (7)
C11	0.105 (9)	0.084 (9)	0.086 (8)	0.034 (7)	0.019 (7)	0.044 (7)
C12	0.080 (8)	0.089 (9)	0.111 (10)	−0.002 (7)	0.009 (7)	0.026 (8)

Geometric parameters (Å, °)

Sn1—O1	2.034 (6)	C4—C5	1.49 (2)
Sn1—C10	2.075 (11)	C4—H4A	0.9700
Sn1—C9	2.082 (11)	C4—H4B	0.9700
Sn1—O2	2.115 (8)	C5—C8	1.51 (2)
Sn1—O3	2.699 (9)	C5—C6	1.54 (2)
Sn1—Cl1i	2.848 (3)	C5—H5	0.9800
Sn2—O1i	2.010 (5)	C6—C7	1.31 (2)
Sn2—C12	2.088 (11)	C6—H6	0.9300
Sn2—C11	2.096 (10)	C7—H7	0.9300
Sn2—O1	2.122 (6)	C8—H8A	0.9700
Sn2—Cl1	2.649 (3)	C8—H8B	0.9700
Sn2—Sn2i	3.2898 (12)	C9—H9A	0.9600
Cl1—Sn1i	2.848 (3)	C9—H9B	0.9600
O1—Sn2i	2.010 (5)	C9—H9C	0.9600
O2—C1	1.262 (16)	C10—H10A	0.9600
O3—C1	1.300 (18)	C10—H10B	0.9600
C1—C3	1.55 (2)	C10—H10C	0.9600
C2—C8	1.494 (19)	C11—H11A	0.9600
C2—C7	1.50 (2)	C11—H11B	0.9600
C2—C3	1.51 (2)	C11—H11C	0.9600
C2—H2	0.9800	C12—H12A	0.9600
C3—C4	1.50 (2)	C12—H12B	0.9600
C3—H3	0.9800	C12—H12C	0.9600
O1—Sn1—C10	104.6 (4)	C1—C3—H3	108.7
O1—Sn1—C9	105.3 (4)	C5—C4—C3	108.8 (15)
C10—Sn1—C9	145.7 (5)	C5—C4—H4A	109.9
O1—Sn1—O2	81.2 (3)	C3—C4—H4A	109.9
C10—Sn1—O2	100.6 (4)	C5—C4—H4B	109.9
C9—Sn1—O2	100.3 (5)	C3—C4—H4B	109.9
O1—Sn1—O3	131.8 (3)	H4A—C4—H4B	108.3
C10—Sn1—O3	85.5 (4)	C4—C5—C8	98.8 (15)
C9—Sn1—O3	87.1 (4)	C4—C5—C6	88.3 (13)
O2—Sn1—O3	50.6 (3)	C8—C5—C6	97.7 (14)
O1—Sn1—Cl1i	74.13 (16)	C4—C5—H5	121.6
C10—Sn1—Cl1i	86.0 (3)	C8—C5—H5	121.6
C9—Sn1—Cl1i	86.2 (4)	C6—C5—H5	121.6
O2—Sn1—Cl1i	155.3 (3)	C7—C6—C5	107.2 (18)
O3—Sn1—Cl1i	154.0 (3)	C7—C6—H6	126.4
O1i—Sn2—C12	114.6 (4)	C5—C6—H6	126.4
O1i—Sn2—C11	111.7 (4)	C6—C7—C2	109.9 (18)
C12—Sn2—C11	133.2 (5)	C6—C7—H7	125.0
O1i—Sn2—O1	74.5 (3)	C2—C7—H7	125.0
C12—Sn2—O1	99.8 (4)	C2—C8—C5	102.3 (14)
C11—Sn2—O1	98.5 (4)	C2—C8—H8A	111.3
O1i—Sn2—Cl1	79.31 (17)	C5—C8—H8A	111.3
C12—Sn2—Cl1	91.0 (4)	C2—C8—H8B	111.3
C11—Sn2—Cl1	91.0 (3)	C5—C8—H8B	111.3
O1—Sn2—Cl1	153.80 (17)	H8A—C8—H8B	109.2
O1i—Sn2—Sn2i	38.43 (16)	Sn1—C9—H9A	109.5
C12—Sn2—Sn2i	111.3 (4)	Sn1—C9—H9B	109.5
C11—Sn2—Sn2i	108.8 (3)	H9A—C9—H9B	109.5
O1—Sn2—Sn2i	36.06 (15)	Sn1—C9—H9C	109.5
Cl1—Sn2—Sn2i	117.74 (7)	H9A—C9—H9C	109.5
Sn2—Cl1—Sn1i	81.42 (7)	H9B—C9—H9C	109.5
Sn2i—O1—Sn1	125.1 (3)	Sn1—C10—H10A	109.5
Sn2i—O1—Sn2	105.5 (3)	Sn1—C10—H10B	109.5
Sn1—O1—Sn2	129.3 (3)	H10A—C10—H10B	109.5
C1—O2—Sn1	113.3 (10)	Sn1—C10—H10C	109.5
C1—O3—Sn1	83.5 (8)	H10A—C10—H10C	109.5
O2—C1—O3	112.1 (13)	H10B—C10—H10C	109.5
O2—C1—C3	117.7 (16)	Sn2—C11—H11A	109.5
O3—C1—C3	130.1 (15)	Sn2—C11—H11B	109.5
C8—C2—C7	92.7 (16)	H11A—C11—H11B	109.5
C8—C2—C3	102.9 (15)	Sn2—C11—H11C	109.5
C7—C2—C3	96.9 (16)	H11A—C11—H11C	109.5
C8—C2—H2	119.7	H11B—C11—H11C	109.5
C7—C2—H2	119.7	Sn2—C12—H12A	109.5
C3—C2—H2	119.7	Sn2—C12—H12B	109.5
C4—C3—C2	103.5 (14)	H12A—C12—H12B	109.5
C4—C3—C1	118.3 (17)	Sn2—C12—H12C	109.5
C2—C3—C1	108.7 (15)	H12A—C12—H12C	109.5
C4—C3—H3	108.7	H12B—C12—H12C	109.5
C2—C3—H3	108.7

Symmetry codes: (i) −x+1, −y+1, −z+2.