Dimeric ethyl­tin(IV)–dibromide–hydroxide–N,N-di­methyl­formamide

Di-μ-hydroxido-bis­[di­bromido­(di­methyl­formamide-κO)ethyl­tin(IV)], [Sn₂Br₄(C₂H₅)₂(OH)₂(C₃H₇NO)₂], was prepared from ethyl­tin(IV) bromide and N,N-di­methyl­formamide (DMF) in air. The crystal structure exhibits the typical structural features of dimeric Lewis-base-stabilized monoorganotin(IV)–dihalide–hydroxides, RSnHal₂(OH), i.e. two octa­hedrally coordinated Sn atoms are linked together via two bridging hydroxide groups, resulting in a centrosymmetric four-membered rhomboid-like Sn–OH ring with acute angles at the Sn atom, obtuse angles at the O atoms and two different tin–oxygen bond lengths. With the shorter bond trans to the ethyl group, this observation underlines once more the so-called trans-strengthening effect in monoorganotin(IV) com­pounds with octa­hedrally coordinated Sn atoms. Differences and similarities in the bond lengths and angles in the four-membered Sn–OH rings have been worked out for the rings in dimeric diorganotin(IV)–halide–hydroxides, [R₂SnHal(OH)]₂, and hydrates of dimeric tin(IV)–trihalide–hydroxide–aqua–hydrates, [SnHal₃(OH)(H₂O)]₂·nH₂O.

1. Chemical context

The title com­pound ethyl­tin(IV)–dibromide–hydroxide N,N-di­methyl­formamide solvate, [EtSnBr₂(OH)·DMF]₂, belongs to the class of monoorganotin(IV)–dihalide–hydroxides, RSnHal₂(OH), representing the first hydrolysis products of the corresponding monoorganotin(IV)–trihalides, RSnHal₃. Since the basic work of Lecomte et al. (1976), it has been well established that this class of com­pounds crystallizes as dimeric Lewis base (LB)–Brønstedt base (BB)-stabilized adducts, [RSnHal₂(OH)LB]₂·nBB. Depending on LB and BB, four different subclasses of dimeric monoorganotin(IV)–dihalide–hydroxides can be distinguished: (i) the subclass of dimeric dihalide–hydroxide–aqua com­plexes, [RSnHal₂(OH)(H₂O)]₂, with LB = H₂O and n = 0, (ii) the subclass of dihalide–hydroxide–solvate com­plexes, [RSnHal₂(OH)LB]₂, with LB other than H₂O and n = 0, (iii) the subclass of dihalide–hydroxide–aqua–hydrates, [RSnHal₂(OH)(H₂O)]₂·nBB, with LB = BB = H₂O, and (iv) the subclass of dihalide–hydroxide–aqua–solvates, [RSnHal₂(OH)(H₂O)]₂·nBB, with LB = H₂O and BB = other than H₂O.

Up to now, the solid-state structures of subclass i have been described for Hal = Cl and R = Et (Lecomte et al., 1976), R = ⁱPr, ⁱBu (Puff & Reuter, 1989), R = ⁿBu (Holmes et al., 1988) and R = (6,6-di­methyl­bicyclo[3.1.1]hept-2-yl)methyl (Beckmann et al., 2009), but for subclass ii, only the crystal structure of the isobutyl com­pound with Hal = Cl and LB = DMF (Reuter & Ye, 2013) is known. In the case of subclass iii, only the single-crystal structure determination of the methyl com­pound with Hal = Cl and n = 3 (Johnson & Knobler, 1994) exists and for subclass iv, the n-butyl com­pounds with Hal = Cl, BB = methyl­benzo­thia­zole and n = 4 (Wei, 1994), and BB = dimethyl cyano­carbonodi­thio­imidate and n = 4 (Mbaye et al., 2023) or n = 2 (Diop et al., 2022) are available.

The title com­pound, belonging to subclass ii, was found accidentally as a hydrolysis product of humid air during an attempt to synthesize a com­plex of ethyl­tin(IV)–tribromide with DMF and represents the first structurally characterized monoorganotin(IV)–hydroxide–dihalide with bromine as the halide.

2. Structural commentary

The title com­pound crystallizes in the monoclinic space group P2₁/c, as was unambiguously confirmed from systematic absence conditions. The unit cell contains two dimeric centrosymmetric mol­ecules (Fig. 1), resulting in half a mol­ecule in the asymmetric unit. The mol­ecule exhibits the typical structural features of the monoorganotin(IV)–dihalide–hy­dro­xides, i.e. two octa­hedrally coordinated Sn atoms are linked together via two bridging hydroxide groups whereby a planar four-membered Sn–OH ring results.

Figure 1 Displacement ellipsoid plot of the dimeric centrosymmetric mol­ecule found in the crystal of [EtSnBr2(OH)·DMF]2, showing the atom numbering of the asymmetric unit. With the exception of the H atoms, which are shown as spheres of arbitrary radius, all other atoms are drawn with displacement ellipsoids at the 40% probability level.

This Sn–OH ring (Fig. 2) has a characteristic rhomboid-like shape with acute [70.01 (8)°] angles at the Sn atoms, obtuse angles [109.99 (8)°] at the O atoms and two distinct different tin–oxygen bond lengths [2.071 (2) and 2.1461 (1) Å], the shorter of which is opposite to the organic group. This kind of bond-length shortening, designated in the literature as trans-strengthening (Paseshnitchenko et al., 1985; Buslaev et al., 1989), is typically found in the case of monoorganotin(IV) com­pounds with tin in a sixfold octa­hedral coordination.

Figure 2 Displacement ellipsoid plot of the centrosymmetric four-membered tin–oxygen ring of the [EtSnBr2(OH)·DMF]2 mol­ecule, highlighting selected bond lengths (Å), angles (°) and distances (Å) from the Sn–O reference plane in square brackets. With the exception of the H atoms, which are shown as spheres of arbitrary radius, all other atoms are drawn with displacement ellipsoids at the 40% probability level. For clarity, ethyl groups are stripped down to the Sn—C bonds drawn as shortened sticks. Inter­molecular O—H⋯Br hydrogen bonds are indicated as dashed sticks in brown. Descriptors trans and cis refer to the position of the corres­ponding bonds with respect to the tin–carbon bond of the ethyl group.

Four-membered Sn–OH rings are structure-dominating features in many organic and inorganic tin(IV) com­pounds. Thus, they occur, for example, in the dimeric diorganotin(IV)–halide–hydroxides, [R₂SnHal(OH)]₂, with trigonal-bipyrami­dally coordinated Sn atoms. There the bond angles are in the same order; different Sn—O bond lengths, however, result from the axial and equatorial positions of the hydroxide groups within the trigonal-bipyramidal coordination of the Sn atoms (cf. Reuter, 2022). A somewhat different geometry is observed in the case of the four-membered Sn–OH rings of the dimeric tin(IV)–trihalide–hydroxide–aqua com­plexes, [SnHal₃(OH)(H₂O)]₂, where the Sn atoms are also octa­hedrally coordinated. These com­pounds constitute the pure inorganic equivalents of the class of com­pounds discussed here with an additional halide atom instead of the organic group R. In analogy to the dimeric monoorganotin(IV)–dihalide–aqua–com­plexes, these inorganic counterparts can be divided into similar subclasses. For Hal = Br, the structures of only two polymorphs (Howie et al., 2005; de Lima et al., 2010) of a hydrate (subclass iii), with 3.5 additional water mol­ecules, are actually known. In both, the dimeric mol­ecules are noncentrosymmetric and the Sn–OH rings are not planar, but only slightly buckled. Nevertheless, these rings exhibit a geometry with similar bond angles at the oxygen [mean value: 108.4 (5)°, 4 data points] and the Sn atoms [mean value: 71.6 (3)°, 4 data points], but the Sn—O bond lengths become more equal [2.081 (1)–2.072 (8) Å] so that the rings adopt a more rhombus-like shape.

The C—C distance [C1—C2 = 1.485 (5) Å] in the ethyl group is to some extent shorter than the value of 1.513 (14) Å evaluated by Allen et al. (1987) for the mean distance between two sp³-hybridized C atoms. This deviation is probably caused by atom vibration, as indicated by the displacement ellipsoids (Fig. 1). The Sn—C distance [Sn—C = 2.228 (2) Å] is enlarged com­pared to the sum (2.15 Å) of the normal co­va­lent radii (Cordero et al., 2008) of tin (1.39 Å) and carbon (0.76 Å), but is in the same order of magnitude as the Sn—C bond length [2.20 (3) Å] found in [EtSnCl₂(OH)·H₂O]₂ (Lecomte et al., 1976). Much shorter tin–carbon bonds [2.139 (4) and 2.130 (4) Å] have been reported for the corresponding DMF com­pound with R = ⁱBu and Hal = Cl (Reuter & Ye, 2013).

Both tin–bromine bonds are of different lengths with the longer one [2.6360 (3) Å] in the case of the in-plane (ip) Br1 atom and the shorter one [2.5893 (4) Å] in the case of the out-of-plane (oop) Br2 atom. The reason for this obviously arises from the fact that the first is involved in a hydrogen bond with the hydroxide group of a neighbouring mol­ecule (see below), while the second is only involved in van der Waals inter­actions. It is notable that both values are markedly longer (0.069 and 0.080 Å) than the tin–bromine distances in the above-mentioned tin(IV)–tribromide–hydroxide–aqua–hy­drates [mean Sn—Br_ip = 2.509 (5) Å, 8 data points; mean Sn—Br_oop = 2.567 (14) Å, 4 data points].

The coordinated DMF mol­ecule is almost planar, as the distances of the O, C and N atoms from the least-squares plane indicate (Fig. 3). The coordinative bond has a length of 2.177 (2) Å, while the bond angle at the O atom is 126.2 (2)°. Both values differ significantly from the corresponding values [2.210 (3)/2.202 (4) Å and 120.8 (3)/124.8 (4)°] observed in the noncentrosymmetric mol­ecules of [ⁱBuSnCl₂(OH)(DMF)]₂ (Reuter & Ye, 2013). The angle between the least-squares plane through the non-H atom of the DMF mol­ecule and the Sn—O_DMF bond length is 3.12 (8)°.

Figure 3 Displacement ellipsoid plot of the DMF mol­ecule, with selected bond lengths (Å), angles (°) and distances (Å) from the least-squares plane through the non-H atoms in square brackets. The dative Sn⋯O bond is indicated as a shortened stick.

Structural distortion of the DMF mol­ecule as a result of its coordinative bond to the Sn atom is well expressed and concerns not only the bond lengths but also the bond angles. Structural data for pure DMF have been determined twice (Borrmann et al., 2000; Ratajczyk et al., 2019) under normal pressure and at a temperature of 100 K. Both crystallize in the triclinic space group P, with two different mol­ecules in the asymmetric unit. As the individual structure parameters within both mol­ecules and between the different measurements differ to some extent, in the following, the mean values of each four data points are used. Most notable are the changes in bond lengths: thus, the carbon–oxygen distance increases by 0.031 Å from 1.229 (2) Å in pure DMF to 1.260 (4) Å in the coordinated molecule; simultaneously, the carbon–nitro­gen distance decreases by 0.038 Å from 1.339 (2) to 1.301 (4) Å, while the distances between the methyl C atoms and the N atoms remain mostly unaffected [cis-CH₃—N(pure/coordinated) = 1.453 (2)/1.457 (6) Å and trans-CH₃—N(pure/coordinated) = 1.454 (2)/1.461 (5) Å]. The greatest changes of the bond angles are observed for O—C—N, decreasing by 2.3° from 125.4 (2)° in pure DMF to 123.1 (3)° in the coordinated mol­ecule, and to a smaller extent (0.8°) for CH₃—N—CH₃, increasing from 117.2 (3) to 118.0 (3)°. The changes of the CH—N—CH₃ angles range from −0.4 to −0.5°.

3. Supra­molecular features

In the solid, hydrogen bonds exist between the hydroxide groups and the Br1 atoms of adjacent mol­ecules, as the space-filling model (Fig. 4) using the van der Waals radii of Mantina et al. (2009) indicates. The resulting chain-like arrangement of the hydrogen-bonded mol­ecules (Fig. 5) takes place in the direction of the crystallographic a axis. With a donor–acceptor distance of 3.283 (2) Å between the Br and O atoms, they rank as strong. The bridging angle at the H atom is 164.8°. As the second Br atom (Br2) does not take part in any hydrogen bonds, the inter­actions between the individual chains are confined to van der Waals contacts (Fig. 6).

Figure 4 Space-filling model of the [EtSn(OH)Br2·DMF]2 mol­ecule, showing the overlap of the H and Br atoms in the region of the hydrogen-bridging bond. These atoms are visualized as truncated two-coloured spheres. Atom colours and van der Waals radii (Å) are as follows: Br = brown/1.83, H = white/1.10, C = grey/1.70, O = red/1.52, N = blue/1.55 and Sn = brass/2.17.

Figure 5 Stick-model showing in detail the chain-like arrangement of the [EtSn(OH)Br2·DMF]2 mol­ecules resulting from inter­molecular O—H⋯Br hydrogen bonds (red dashed sticks). The image shows three com­plete mol­ecules with their hydrogen bonds to neighbouring mol­ecules. Two-coloured sticks based on atom colours are as follows: Br = brown, H = white, C = grey, O = red, N = blue and Sn = brass

Figure 6 Perspective view into the crystal structure of [EtSn(OH)Br2·DMF]2 looking down the crystallographic a axis and showing the arrangement of the chains of hydrogen-bonded [EtSn(OH)Br2·DMF]2 mol­ecules in relation to the unit cell (a axis = red, b axis = green and c axis = blue).

4. Synthesis and crystallization

In a fumehood, 0.39 g (1 mmol) of ethyl­tin(IV) tribromide, C₂H₅Br₃Sn, prepared from ethyl­tin(IV) trichloride via halide exchange with an excess of potassium bromide in dry acetone was mixed with 2 ml N,N-di­methyl­formamide (DMF) on a petri dish with a glass lid. Crystal formation was checked every day using an optical microscope. The first crystals of the title com­pound appeared after two weeks.

5. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 1. The positions of all H atoms were clearly identified in difference Fourier syntheses. Those of the organic groups were refined with calculated positions (–CH₃ = 0.96 Å, –CH₂– = 0.97 Å and –CH– = 0.93 Å) and common U_iso(H) parameters for each individual group. The position of the H atom of the OH group was refined with a fixed O—H distance of 0.96 Å before it was fixed and allowed to ride on the parent O atom with an isotropic displacement parameter.

Table 1
Experimental details

Crystal data
Chemical formula	[Sn2Br4(C2H5)2(OH)2(C3H7NO)2]
Mr	795.35
Crystal system, space group	Monoclinic, P21/c
Temperature (K)	100
a, b, c (Å)	7.0415 (3), 17.9349 (8), 9.0148 (5)
β (°)	100.812 (2)
V (Å^3)	1118.26 (9)
Z	2
Radiation type	Mo Kα
μ (mm^−1)	9.39
Crystal size (mm)	0.26 × 0.16 × 0.12
Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Krause et al., 2015)
Tmin, Tmax	0.514, 0.723
No. of measured, independent and observed [I > 2σ(I)] reflections	84799, 2687, 2455
Rint	0.037
(sin θ/λ)max (Å^−1)	0.661
Refinement
R[F^2 > 2σ(F^2)], wR(F^2), S	0.018, 0.046, 1.07
No. of reflections	2687
No. of parameters	107
H-atom treatment	Only H-atom displacement parameters refined
Δρmax, Δρmin (e Å^−3)	1.07, −0.50
Computer programs: APEX2 and SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL2014 (Sheldrick, 2015), DIAMOND (Brandenburg, 2006), Mercury (Macrae et al., 2020) and publCIF (Westrip, 2010).

Supporting information

Computing details

Di-µ-hydroxido-bis[dibromido(dimethylformamide-κO)ethyltin(IV)]

Crystal data

[Sn2Br4(C2H5)2(OH)2(C3H7NO)2]	F(000) = 744
Mr = 795.35	Dx = 2.362 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 7.0415 (3) Å	Cell parameters from 9635 reflections
b = 17.9349 (8) Å	θ = 2.9–29.1°
c = 9.0148 (5) Å	µ = 9.39 mm^−1
β = 100.812 (2)°	T = 100 K
V = 1118.26 (9) Å^3	Plate, colourless
Z = 2	0.26 × 0.16 × 0.12 mm

Data collection

Bruker APEXII CCD diffractometer	2455 reflections with I > 2σ(I)
φ and ω scans	Rint = 0.037
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	θmax = 28.0°, θmin = 3.0°
Tmin = 0.514, Tmax = 0.723	h = −9→9
84799 measured reflections	k = −23→23
2687 independent reflections	l = −11→11

Refinement

Refinement on F^2	Hydrogen site location: mixed
Least-squares matrix: full	Only H-atom displacement parameters refined
R[F^2 > 2σ(F^2)] = 0.018	w = 1/[σ^2(Fo^2) + (0.0201P)^2 + 2.2958P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.046	(Δ/σ)max = 0.002
S = 1.07	Δρmax = 1.07 e Å^−3
2687 reflections	Δρmin = −0.50 e Å^−3
107 parameters	Extinction correction: SHELXL2014 (Sheldrick, 2015), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.00097 (16)
Primary atom site location: structure-invariant direct methods

Special details

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

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Sn1	0.13007 (2)	0.55518 (2)	0.14030 (2)	0.01599 (6)
C1	0.0660 (3)	0.59933 (18)	0.3566 (3)	0.0203 (6)
H11	0.0714	0.6534	0.3552	0.078 (7)*
H12	−0.0642	0.5850	0.3656	0.078 (7)*
C2	0.2042 (6)	0.5712 (3)	0.4897 (4)	0.0549 (12)
H21	0.2043	0.5177	0.4886	0.078 (7)*
H22	0.1660	0.5885	0.5805	0.078 (7)*
H23	0.3316	0.5892	0.4861	0.078 (7)*
Br1	0.50184 (4)	0.58619 (2)	0.17646 (3)	0.02061 (8)
Br2	0.04385 (4)	0.67775 (2)	−0.00891 (4)	0.02626 (8)
O1	0.1412 (2)	0.49890 (10)	−0.0585 (2)	0.0179 (4)
H1	0.2590	0.4824	−0.0870	0.051 (12)*
O2	0.2199 (3)	0.44926 (11)	0.2493 (2)	0.0226 (4)
N1	0.3916 (4)	0.34269 (14)	0.2843 (3)	0.0251 (5)
C3	0.3503 (4)	0.40693 (15)	0.2192 (3)	0.0204 (5)
H3	0.4204	0.4223	0.1469	0.056 (5)*
C4	0.2812 (6)	0.3145 (2)	0.3939 (5)	0.0461 (10)
H41	0.3403	0.3310	0.4933	0.056 (5)*
H42	0.2795	0.2610	0.3910	0.056 (5)*
H43	0.1512	0.3331	0.3697	0.056 (5)*
C5	0.5454 (5)	0.29569 (19)	0.2467 (4)	0.0390 (8)
H51	0.6023	0.3198	0.1705	0.056 (5)*
H52	0.4924	0.2485	0.2095	0.056 (5)*
H53	0.6425	0.2880	0.3354	0.056 (5)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Sn1	0.01125 (9)	0.01715 (10)	0.01884 (10)	0.00173 (6)	0.00092 (7)	−0.00585 (7)
C1	0.0071 (10)	0.0454 (17)	0.0086 (12)	0.0054 (11)	0.0023 (9)	−0.0085 (11)
C2	0.039 (2)	0.099 (4)	0.0262 (19)	0.000 (2)	0.0046 (16)	−0.019 (2)
Br1	0.01178 (12)	0.02018 (14)	0.02940 (16)	0.00052 (9)	0.00265 (10)	−0.00779 (11)
Br2	0.02073 (14)	0.01634 (14)	0.03855 (18)	0.00282 (10)	−0.00257 (12)	−0.00237 (11)
O1	0.0115 (8)	0.0210 (10)	0.0212 (10)	0.0010 (7)	0.0031 (7)	−0.0074 (8)
O2	0.0190 (9)	0.0265 (10)	0.0218 (10)	0.0020 (8)	0.0024 (8)	0.0001 (8)
N1	0.0238 (12)	0.0240 (13)	0.0248 (13)	−0.0017 (10)	−0.0028 (10)	0.0061 (10)
C3	0.0200 (13)	0.0194 (13)	0.0195 (14)	−0.0023 (10)	−0.0020 (11)	−0.0005 (11)
C4	0.047 (2)	0.046 (2)	0.046 (2)	−0.0021 (17)	0.0109 (18)	0.0257 (18)
C5	0.0422 (19)	0.0231 (16)	0.048 (2)	0.0112 (14)	−0.0003 (16)	0.0047 (15)

Geometric parameters (Å, º)

Sn1—O1	2.071 (2)	O1—H1	0.9600
Sn1—O1^i	2.146 (2)	O2—C3	1.260 (3)
Sn1—O2	2.177 (2)	N1—C3	1.301 (4)
Sn1—C1	2.228 (2)	N1—C4	1.457 (4)
Sn1—Br2	2.5893 (4)	N1—C5	1.461 (4)
Sn1—Br1	2.6360 (3)	C3—H3	0.9300
C1—C2	1.485 (5)	C4—H41	0.9600
C1—H11	0.9700	C4—H42	0.9600
C1—H12	0.9700	C4—H43	0.9600
C2—H21	0.9600	C5—H51	0.9600
C2—H22	0.9600	C5—H52	0.9600
C2—H23	0.9600	C5—H53	0.9600
O1—Sn1^i	2.146 (2)
O1—Sn1—O1^i	70.01 (8)	H21—C2—H23	109.5
O1—Sn1—O2	84.87 (8)	H22—C2—H23	109.5
O1^i—Sn1—O2	85.71 (7)	Sn1—O1—Sn1^i	109.99 (8)
O1—Sn1—C1	167.78 (9)	Sn1—O1—H1	123.8
O1^i—Sn1—C1	98.51 (8)	Sn1^i—O1—H1	121.8
O2—Sn1—C1	90.26 (10)	C3—O2—Sn1	126.16 (18)
O1—Sn1—Br2	90.42 (5)	C3—N1—C4	120.7 (3)
O1^i—Sn1—Br2	95.65 (5)	C3—N1—C5	121.2 (3)
O2—Sn1—Br2	174.34 (5)	C4—N1—C5	118.0 (3)
C1—Sn1—Br2	94.97 (8)	O2—C3—N1	123.1 (3)
O1—Sn1—Br1	90.69 (5)	O2—C3—H3	118.4
O1^i—Sn1—Br1	159.59 (5)	N1—C3—H3	118.4
O2—Sn1—Br1	86.02 (5)	N1—C4—H41	109.5
C1—Sn1—Br1	100.16 (7)	N1—C4—H42	109.5
Br2—Sn1—Br1	90.900 (11)	H41—C4—H42	109.5
C2—C1—Sn1	112.1 (2)	N1—C4—H43	109.5
C2—C1—H11	109.2	H41—C4—H43	109.5
Sn1—C1—H11	109.2	H42—C4—H43	109.5
C2—C1—H12	109.2	N1—C5—H51	109.5
Sn1—C1—H12	109.2	N1—C5—H52	109.5
H11—C1—H12	107.9	H51—C5—H52	109.5
C1—C2—H21	109.5	N1—C5—H53	109.5
C1—C2—H22	109.5	H51—C5—H53	109.5
H21—C2—H22	109.5	H52—C5—H53	109.5
C1—C2—H23	109.5

Symmetry code: (i) −x, −y+1, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···Br1^ii	0.96	2.35	3.283 (2)	165

Symmetry code: (ii) −x+1, −y+1, −z.