supplementary materials


mw2103 scheme

Acta Cryst. (2013). E69, m329    [ doi:10.1107/S1600536813012828 ]

cis-Tetrakis([mu]-N-phenylacetamidato)-[kappa]4N:O;[kappa]4O:N-bis[(benzonitrile-[kappa]N)rhodium(II)](Rh-Rh)

C. T. Eagle, F. Quarshie, M. E. Ketron and N. Atem-Tambe

Abstract top

The complex molecule of the title compound, [Rh2{N(C6H5)COCH3}4(C6H5CN)2], exhibits crystallographically imposed centrosymmetry. The four acetamide ligands bridging the dirhodium core are arranged in a 2,2-cis manner, with two N atoms and two O atoms coordinating to the unique RhII atom cis to one another. The Neq-Rh-Rh-Oeq torsion angles on the acetamide bridges vary between 1.62 (4) and 1.78 (4)°. The Rh-Rh bond length is 2.4319 (3) Å. The axial nitrile ligand completes the distorted octahedral coordination sphere and shows a non-linear coordination with an Rh-N-C bond angle of 167.14 (15)°, while the N-C bond length is 1.135 (3) Å.

Comment top

Previous papers report the structures of the related complexes 2,2-cis-Rh2[N(C6H5)COCH3]4.2DMSO (Bear et al. 1987), 2,2-trans-Rh2[N(C6H5)COCH3]4.2NCC6H5 (2) (Eagle et al., 2000) and 2,2-trans-Rh2[N(C9H11)COCH3]4.2NCC6H5 (3) (Eagle et al., 2012). The numbering scheme of the title compound was adapted from that of compound 2.

The axial rhodium-nitrogen-carbon bond angle for 1, 167.14 (15)°, (Fig. 1) is distinctly non-linear which is different from those found in 2 (178.5 (5)° and 169.3 (5)°) and 3 (180°; imposed by space group symmetry). The axial carbon-nitrogen bond length in 1 is 1.135 (3) Å which is comparable to the corresponding distances found in 2 (1.135 (8) and 1.145 (8) Å) and slightly longer than that in 3 (1.106 (6) Å). Compound 1 has pseudo four-fold symmetry with torsion angles on each acetamide bridge varying between 1.62 (4)° and 1.78 (4)°. These can be compared to the range of 9.03° and 11.89° in 2 and 1.12 (9)° in 3. A packing diagram of the structure is shown in Fig. 2 and indicates that van der Waals forces hold the molecules of 1 together.

The infrared absorption spectrum of 1 showed bands at 2359 and 2320 cm-1 attributable to carbon-nitrogen bond stretching modes. The corresponding band for uncomplexed benzonitrile appears at 2228 cm-1. This indicates that there is a shortening of the carbon-nitrogen bond and a stronger σ-interaction to the rhodium metal compared to the π-back-bonding which occurs upon complexation with cis-tetrakis[µ-N-(phenyl)acetamidato]-κ4N:O;κ4O:N rhodium(II)].

Related literature top

For related structures, see: Bear et al. (1987) and Eagle et al. (2000, 2012).

Experimental top

Approximately 10 mg of 2,2-cis-[Rh2(N(C6H5)COCH3)4] was dissolved in 18 mL of dichloromethane. 10 µL of benzonitrile was then added to this solution, via a gas tight syringe, turning the solution from a green to a light blue color. Crystals grew over a one week period via vapor diffusion with acetone. From the structure determination compound 1 is an adduct of cis-tetrakis[µ-N-(phenyl)acetamidato]-κ4N:O;κ4O:N rhodium(II)] with benzonitrile in each axial site.

Refinement top

H-atoms were included in calculated positions with C—H = 0.94 - 0.97 Å and included as riding contributions with isotropic displacement parameters 1.2 - 1.5 times those of the attached atom.

Atoms C22 and C23 exhibit slightly extended displacement perpendicular to the plane of the ring containing them. This is likely due to a combination of some rotational disorder about the N3-Rh1 bond and also due to normal stacking errors, as evidenced in similar displacement amplitudes in the adjacent ring (C5 to C10).

There are three strong reflections missing. They may have been low-angle reflections behind the beamstop shadow or the relections may have overloaded in the detector (even in the overload-correction mode).

Computing details top

Data collection: CrystalClear-SM Auto (Rigaku, 2011); cell refinement: CrystalClear-SM Auto (Rigaku, 2011); data reduction: CrystalClear-SM Auto (Rigaku, 2011); program(s) used to solve structure: SIR2004 (Burla et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CrystalStructure (Rigaku, 2010); software used to prepare material for publication: CrystalStructure (Rigaku, 2010).

Figures top
[Figure 1] Fig. 1. ORTEP of the title compound showing 30% probability ellipsoids. Hydrogen atoms are drawn as small spheres.
[Figure 2] Fig. 2. Packing diagram for the title compound as seen along the b axis.
cis-Tetrakis(µ-N-phenylacetamidato)-κ4N:O;κ4O:N-bis[(benzonitrile-κN)rhodium(II)](RhRh) top
Crystal data top
[Rh2(C8H8NO)4(C7H5N)2]F(000) = 964.00
Mr = 948.69Dx = 1.476 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71075 Å
Hall symbol: -P 2ynCell parameters from 20104 reflections
a = 10.2115 (7) Åθ = 3.2–27.5°
b = 9.9667 (7) ŵ = 0.82 mm1
c = 21.3672 (16) ÅT = 223 K
β = 100.971 (7)°Prism, red
V = 2134.9 (3) Å30.49 × 0.35 × 0.16 mm
Z = 2
Data collection top
Rigaku XtaLAB mini
diffractometer
4413 reflections with F2 > 2σ(F2)
Detector resolution: 6.827 pixels mm-1Rint = 0.023
ω scansθmax = 27.5°
Absorption correction: multi-scan
(REQAB; Rigaku, 1998)
h = 1313
Tmin = 0.689, Tmax = 0.880k = 1212
21686 measured reflectionsl = 2727
4872 independent reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.021Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.054H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0268P)2 + 0.9991P]
where P = (Fo2 + 2Fc2)/3
4872 reflections(Δ/σ)max = 0.005
264 parametersΔρmax = 0.39 e Å3
0 restraintsΔρmin = 0.34 e Å3
Primary atom site location: structure-invariant direct methods
Crystal data top
[Rh2(C8H8NO)4(C7H5N)2]V = 2134.9 (3) Å3
Mr = 948.69Z = 2
Monoclinic, P21/nMo Kα radiation
a = 10.2115 (7) ŵ = 0.82 mm1
b = 9.9667 (7) ÅT = 223 K
c = 21.3672 (16) Å0.49 × 0.35 × 0.16 mm
β = 100.971 (7)°
Data collection top
Rigaku XtaLAB mini
diffractometer
4872 independent reflections
Absorption correction: multi-scan
(REQAB; Rigaku, 1998)
4413 reflections with F2 > 2σ(F2)
Tmin = 0.689, Tmax = 0.880Rint = 0.023
21686 measured reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.021H-atom parameters constrained
wR(F2) = 0.054Δρmax = 0.39 e Å3
S = 1.03Δρmin = 0.34 e Å3
4872 reflectionsAbsolute structure: ?
264 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

Refinement. Refinement was performed using all reflections. The weighted R-factor (wR) and goodness of fit (S) are based on F2. R-factor (gt) are based on F. The threshold expression of F2 > 2.0 σ(F2) is used only for calculating R-factor (gt).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Rh10.987101 (12)0.041420 (12)0.552011 (5)0.02306 (5)
O11.07504 (13)0.13034 (12)0.59283 (5)0.0343 (3)
O20.80499 (13)0.05051 (13)0.53865 (6)0.0347 (3)
N10.89591 (14)0.20483 (14)0.50448 (7)0.0279 (3)
N21.17358 (13)0.12274 (14)0.55998 (6)0.0267 (3)
N30.95315 (16)0.11158 (17)0.64638 (7)0.0365 (4)
C11.12289 (18)0.21431 (17)0.55768 (8)0.0311 (4)
C30.75803 (17)0.10896 (17)0.48590 (8)0.0299 (4)
C50.83771 (17)0.30448 (18)0.53903 (8)0.0321 (4)
C111.23573 (16)0.18266 (18)0.61898 (8)0.0292 (4)
C180.89020 (19)0.24259 (19)0.74055 (8)0.0358 (4)
C170.92479 (19)0.16727 (19)0.68819 (8)0.0356 (4)
C161.2654 (2)0.1039 (2)0.67331 (9)0.0400 (5)
C21.2038 (3)0.3258 (2)0.59377 (10)0.0456 (5)
C131.3258 (3)0.3739 (3)0.68191 (11)0.0509 (6)
C40.61698 (19)0.1591 (3)0.48041 (10)0.0445 (5)
C190.7609 (3)0.2429 (3)0.75172 (11)0.0524 (6)
C141.3553 (2)0.2951 (3)0.73554 (10)0.0512 (6)
C100.9057 (3)0.4201 (3)0.55934 (13)0.0560 (7)
C60.7144 (2)0.2840 (3)0.55464 (12)0.0545 (6)
C80.7233 (3)0.4990 (3)0.60496 (15)0.0680 (8)
C121.2654 (2)0.31854 (19)0.62366 (10)0.0409 (5)
C70.6577 (3)0.3819 (3)0.58741 (15)0.0697 (8)
C200.7314 (3)0.3185 (3)0.80154 (11)0.0544 (6)
C90.8477 (3)0.5177 (3)0.59178 (17)0.0758 (9)
C210.8268 (3)0.3914 (3)0.83920 (11)0.0561 (6)
C230.9875 (3)0.3163 (3)0.77885 (11)0.0611 (7)
C151.3258 (3)0.1600 (3)0.73092 (10)0.0504 (6)
C220.9550 (3)0.3898 (4)0.82871 (13)0.0771 (9)
H91.24460.01190.67100.0480*
H10A1.25020.29240.63460.0548*
H10B1.26820.35830.56940.0548*
H10C1.14500.39860.60060.0548*
H111.34660.46580.68450.0611*
H12A0.57040.15110.43660.0534*
H12B0.57140.10590.50770.0534*
H12C0.61840.25240.49340.0534*
H130.69410.19230.72580.0629*
H141.39500.33290.77490.0614*
H150.99200.43350.55120.0672*
H160.66840.20340.54310.0653*
H170.68340.56620.62590.0816*
H181.24460.37350.58740.0491*
H190.57330.36710.59760.0836*
H200.64390.31910.80930.0653*
H210.89460.59720.60480.0910*
H220.80520.44310.87260.0674*
H231.07530.31680.77130.0733*
H241.34680.10530.76730.0604*
H251.02150.43910.85560.0926*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Rh10.03062 (7)0.02261 (7)0.01845 (7)0.00433 (5)0.01099 (5)0.00399 (5)
O10.0538 (8)0.0259 (6)0.0250 (6)0.0002 (6)0.0122 (6)0.0003 (5)
O20.0396 (7)0.0403 (7)0.0290 (6)0.0155 (6)0.0184 (6)0.0093 (6)
N10.0307 (7)0.0264 (7)0.0280 (7)0.0011 (6)0.0087 (6)0.0042 (6)
N20.0292 (7)0.0268 (7)0.0249 (7)0.0039 (6)0.0076 (6)0.0035 (6)
N30.0406 (9)0.0419 (9)0.0298 (8)0.0058 (7)0.0140 (7)0.0090 (7)
C10.0376 (9)0.0251 (8)0.0308 (9)0.0041 (7)0.0066 (7)0.0008 (7)
C30.0331 (9)0.0286 (9)0.0299 (9)0.0061 (7)0.0110 (7)0.0026 (7)
C50.0323 (9)0.0307 (9)0.0332 (9)0.0018 (7)0.0058 (7)0.0056 (7)
C110.0264 (8)0.0335 (9)0.0275 (8)0.0006 (7)0.0048 (7)0.0063 (7)
C180.0435 (10)0.0405 (10)0.0264 (9)0.0037 (9)0.0148 (8)0.0042 (8)
C170.0404 (10)0.0399 (10)0.0288 (9)0.0032 (8)0.0122 (8)0.0030 (8)
C160.0450 (11)0.0423 (11)0.0320 (10)0.0012 (9)0.0056 (8)0.0006 (8)
C20.0604 (13)0.0352 (10)0.0380 (11)0.0072 (10)0.0009 (10)0.0021 (9)
C130.0508 (12)0.0414 (11)0.0555 (13)0.0017 (10)0.0027 (10)0.0205 (11)
C40.0353 (10)0.0559 (13)0.0456 (11)0.0143 (9)0.0161 (9)0.0126 (10)
C190.0440 (12)0.0684 (15)0.0484 (12)0.0031 (11)0.0178 (10)0.0126 (11)
C140.0416 (11)0.0692 (15)0.0384 (11)0.0033 (11)0.0034 (9)0.0232 (11)
C100.0430 (12)0.0450 (12)0.0852 (18)0.0103 (10)0.0256 (12)0.0277 (12)
C60.0380 (11)0.0518 (13)0.0778 (16)0.0093 (10)0.0219 (11)0.0282 (12)
C80.0578 (15)0.0585 (15)0.091 (2)0.0060 (13)0.0224 (14)0.0397 (15)
C120.0458 (11)0.0316 (10)0.0411 (11)0.0026 (8)0.0025 (9)0.0056 (8)
C70.0437 (13)0.0741 (18)0.098 (2)0.0029 (13)0.0304 (13)0.0401 (17)
C200.0491 (13)0.0688 (16)0.0534 (13)0.0122 (12)0.0301 (11)0.0022 (12)
C90.0659 (17)0.0508 (15)0.116 (3)0.0130 (13)0.0304 (17)0.0484 (16)
C210.0731 (16)0.0614 (15)0.0411 (12)0.0123 (13)0.0293 (11)0.0113 (11)
C230.0485 (13)0.0875 (19)0.0526 (14)0.0088 (13)0.0233 (11)0.0350 (14)
C150.0527 (13)0.0667 (15)0.0285 (10)0.0033 (11)0.0003 (9)0.0007 (10)
C220.0711 (17)0.103 (3)0.0626 (16)0.0158 (17)0.0259 (14)0.0519 (17)
Geometric parameters (Å, º) top
Rh1—Rh1i2.4319 (3)C6—C71.390 (4)
Rh1—O12.0493 (12)C8—C71.362 (4)
Rh1—O22.0438 (14)C8—C91.365 (5)
Rh1—N12.0472 (14)C20—C211.351 (4)
Rh1—N22.0466 (14)C21—C221.369 (5)
Rh1—N32.2229 (16)C23—C221.385 (4)
O1—C11.282 (3)C16—H90.940
O2—C31.278 (2)C2—H10A0.970
N1—C1i1.309 (3)C2—H10B0.970
N1—C51.432 (3)C2—H10C0.970
N2—C3i1.315 (3)C13—H110.940
N2—C111.430 (2)C4—H12A0.970
N3—C171.135 (3)C4—H12B0.970
C1—C21.507 (3)C4—H12C0.970
C3—C41.508 (3)C19—H130.940
C5—C101.373 (3)C14—H140.940
C5—C61.378 (3)C10—H150.940
C11—C161.386 (3)C6—H160.940
C11—C121.387 (3)C8—H170.940
C18—C171.446 (3)C12—H180.940
C18—C191.386 (3)C7—H190.940
C18—C231.374 (3)C20—H200.940
C16—C151.385 (3)C9—H210.940
C13—C141.374 (4)C21—H220.940
C13—C121.393 (3)C23—H230.940
C19—C201.383 (4)C15—H240.940
C14—C151.380 (4)C22—H250.940
C10—C91.390 (5)
Rh1i—Rh1—O189.45 (4)C19—C20—C21120.9 (3)
Rh1i—Rh1—O288.51 (4)C10—C9—C8120.6 (3)
Rh1i—Rh1—N186.26 (5)C20—C21—C22120.0 (3)
Rh1i—Rh1—N287.11 (4)C18—C23—C22119.3 (3)
Rh1i—Rh1—N3176.96 (5)C16—C15—C14120.8 (2)
O1—Rh1—O289.90 (5)C21—C22—C23120.6 (3)
O1—Rh1—N1175.42 (5)C11—C16—H9119.8
O1—Rh1—N288.28 (6)C15—C16—H9119.8
O1—Rh1—N390.46 (6)C1—C2—H10A109.5
O2—Rh1—N188.37 (6)C1—C2—H10B109.5
O2—Rh1—N2175.28 (6)C1—C2—H10C109.5
O2—Rh1—N388.45 (6)H10A—C2—H10B109.5
N1—Rh1—N293.12 (6)H10A—C2—H10C109.5
N1—Rh1—N393.73 (6)H10B—C2—H10C109.5
N2—Rh1—N395.92 (6)C14—C13—H11119.7
Rh1—O1—C1118.76 (10)C12—C13—H11119.7
Rh1—O2—C3120.41 (13)C3—C4—H12A109.5
Rh1—N1—C1i121.73 (12)C3—C4—H12B109.5
Rh1—N1—C5119.35 (11)C3—C4—H12C109.5
C1i—N1—C5118.55 (14)H12A—C4—H12B109.5
Rh1—N2—C3i120.96 (11)H12A—C4—H12C109.5
Rh1—N2—C11119.25 (11)H12B—C4—H12C109.5
C3i—N2—C11119.44 (14)C18—C19—H13120.4
Rh1—N3—C17167.14 (15)C20—C19—H13120.4
O1—C1—N1i123.29 (16)C13—C14—H14120.4
O1—C1—C2114.51 (16)C15—C14—H14120.4
N1i—C1—C2122.20 (17)C5—C10—H15119.7
O2—C3—N2i122.80 (16)C9—C10—H15119.8
O2—C3—C4114.33 (17)C5—C6—H16119.8
N2i—C3—C4122.86 (16)C7—C6—H16119.8
N1—C5—C10120.72 (18)C7—C8—H17120.4
N1—C5—C6120.67 (17)C9—C8—H17120.4
C10—C5—C6118.6 (2)C11—C12—H18119.9
N2—C11—C16119.43 (16)C13—C12—H18119.9
N2—C11—C12121.70 (16)C6—C7—H19119.7
C16—C11—C12118.85 (17)C8—C7—H19119.7
C17—C18—C19121.03 (18)C19—C20—H20119.6
C17—C18—C23118.9 (2)C21—C20—H20119.6
C19—C18—C23120.1 (2)C10—C9—H21119.7
N3—C17—C18178.0 (2)C8—C9—H21119.7
C11—C16—C15120.3 (2)C20—C21—H22120.0
C14—C13—C12120.6 (2)C22—C21—H22120.0
C18—C19—C20119.2 (2)C18—C23—H23120.4
C13—C14—C15119.2 (2)C22—C23—H23120.4
C5—C10—C9120.5 (3)C16—C15—H24119.6
C5—C6—C7120.4 (2)C14—C15—H24119.6
C7—C8—C9119.2 (3)C21—C22—H25119.7
C11—C12—C13120.28 (19)C23—C22—H25119.7
C6—C7—C8120.7 (3)
O1—Rh1—Rh1i—O2i90.08 (4)N1—Rh1—Rh1i—O1i1.62 (4)
O1—Rh1—Rh1i—N1i1.62 (4)N1—Rh1—Rh1i—O2i91.54 (4)
O1—Rh1—Rh1i—N2i91.69 (4)N1—Rh1—Rh1i—N2i86.68 (4)
O2—Rh1—Rh1i—O1i90.08 (4)N2—Rh1—Rh1i—O1i91.69 (4)
O2—Rh1—Rh1i—N1i91.54 (4)N2—Rh1—Rh1i—O2i1.78 (4)
O2—Rh1—Rh1i—N2i1.78 (4)N2—Rh1—Rh1i—N1i86.68 (4)
Symmetry code: (i) x+2, y, z+1.
Acknowledgements top

We thank Dr Lee Daniels of Rigaku Americas for his training on the Rigaku XtaLAB diffractometer and his extended help in the completion of the structure determination. Support was provided by a Start Up Grant from ETSU. We thank Johnson Matthey for their generous loan of rhodium trichloride.

references
References top

Bear, J. L. & Kadish, K. M. (1987). Inorg. Chem. 26, 830–836.

Burla, M. C., Caliandro, R., Camalli, M., Carrozzini, B., Cascarano, G. L., De Caro, L., Giacovazzo, C., Polidori, G. & Spagna, R. (2005). J. Appl. Cryst. 38, 381–388.

Eagle, C. T., Farrar, D. G., Holder, G. N., Pennington, W. T. & Bailey, R. D. (2000). J. Organomet. Chem. 596, 90–94.

Eagle, C. T., Kpogo, K. K., Zink, L. C. & Smith, A. E. (2012). Acta Cryst. E68, m877.

Rigaku (1998). REQAB. Rigaku Corporation, Tokyo, Japan.

Rigaku (2010). CrystalStructure. Rigaku Corporation, Tokyo, Japan.

Rigaku (2011). CrystalClear-SM Auto. Rigaku Corporation, Tokyo, Japan.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.