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Acta Cryst. (2012). E68, m1354-m1355    [ doi:10.1107/S1600536812042286 ]

Bis(diphenyl-p-tolylphosphane-[kappa]P)(2-hydroxy-3,5,7-bromocyclohepta-2,4,6-trienonato-[kappa]2O,O')copper(I)

N. I. Barnard and T. N. Hill

Abstract top

The CuI atom in the title compund, [Cu(C7H2Br3O2)(C19H17P)2], is located on a twofold rotation axis; the 3,5,7-tribromotropolonate anion coordinates as a bidentate ligand with a bite angle of 76.42 (9)°. An intramolecular C-H...O interaction occurs. Within the crystal, extensive weak C-H...[pi] interactions contribute to the herringbone pattern observed in the packing of the molecules.

Comment top

Tropolone and its derivatives have been of interest ever since their first discovery in the early 1940's (Dewar, 1945); they are known to have applications in both pharmacology (Hill & Steyl, 2008) and catalysis (Crous et al., 2005). Bis troplolonato copper(II) complexes are most frequently reported (Ho, 2010; Ho et al., 2009; Chipperfield et al., 1998; Hasegawa et al., 1997). Recently, reseach in this area has been extended to include copper(I) phosphine metal complexes and the effect the troplonato ligand has on the solid state and chemical behaviour of these complexes (Steyl, 2007; Steyl & Roodt, 2006; Roodt et al., 2003). In this paper, the structure of the tropolonato-bis[diphenyl(p-tolyl)-phosphine]copper(I) complex is reported (Fig. 1).

The Cu—O and Cu—P bond distances were found to be 2.090 (1) Å and 2.229 (1) Å respectively and are well within comparable ranges for copper(I) phosphine complexes. the bond angles about the Cu atom show significantly distorted tetrahedral coordination (Table 1). The bidentate bite angle O2—Cu—O2i observed at 76.42 (9)° is close to analogous angles in previously reported structures (Steyl, 2009).

The title compound (I) displays intramolecular C—H···Br interactions with a distance of 3.4666 (5) Å as seen in Figure 2. Figure 3 illustrates the packing diagram for compound (I), a zigzag pattern is adopted with inverted repeating units creating diagonals in all directions. This intricate design is achieved though numerous C—H···π itermolecular interactions see Figure 4. These interactions occur between methyl H atoms of the p-tolyl and phenyl π, phenyl H to p-tolyl π, phenyl H to phenyl π and p-tolyl π to p-tolyl The C—H···π itermolecular interactions range from 3.1816 (1) Å - 3.7267 (2) Å.

Related literature top

For background to tropolone and its derivatives, see: Dewar (1945); Hill & Steyl (2008); Crous et al. (2005). For bis-troplolonato–copper(II) complexes, see: Chipperfield et al. (1998); Hasegawa et al. (1997); Ho (2010); Ho et al. (2009). For work on the effect the troplonato ligand has on the solid state and chemical behaviour of copper(I) phosphine metal complexes, see: Roodt et al. (2003); Steyl (2007, 2009); Steyl & Hill (2009); Steyl & Roodt (2006).

Experimental top

3,5,7-Tribomotropolone (0.3 mmol) was dissolved in methanol (20 ml). To this solution was added Bis(diphenyl(p-tolyl)-phosphine) copper nitrate (0.3 mmol). The resulting mixture was stirred at room temperature for 30 minutes before filtering. The filtrate was then slowly evaporated yielding crystals siutable for X-ray diffraction after 48 h.

Refinement top

Hydroge atoms were placed in calculated positions, and were allowed to ride on their parent C atoms.

The final difference Fouier map had a peak/hole in the vicinity of Br1.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. A view of (I). Displacement ellipsoids are drawn at 50% proabiity level. Hydrogen atoms have been ommited.
[Figure 2] Fig. 2. Intramolecular H···Br interactions (dashed bonds) for the title compound.
[Figure 3] Fig. 3. A packing diagram of the title compound, illustrating the herringbone patturnation as viewed along the [1,0,1] axis. Hydrogen atoms have been ommited.
[Figure 4] Fig. 4. Four differing views highlighting elaborate web of H···π intermolecular interactions (dashed bonds) creating the three dimentional herringbone design, non-relevant hydrogen atoms have been ommited for clarity.
Bis(diphenyl-p-tolylphosphane-κP)(2-hydroxy-3,5,7-bromocyclohepta-2,4,6-trienonato-κ2O,O')copper(I) top
Crystal data top
[Cu(C7H2Br3O2)(C19H17P)2]F(000) = 1944
Mr = 973.95Dx = 1.604 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 8436 reflections
a = 15.4522 (8) Åθ = 2.3–28.4°
b = 13.9073 (8) ŵ = 3.63 mm−1
c = 19.3269 (10) ÅT = 100 K
β = 103.862 (3)°Cuboid, green
V = 4032.4 (4) Å30.18 × 0.09 × 0.06 mm
Z = 4
Data collection top
Bruker X8 APEXII 4K Kappa CCD
diffractometer		5022 independent reflections
Radiation source: sealed tube3970 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.053
Detector resolution: 512 pixels mm-1θmax = 28.4°, θmin = 2°
φ and ω scansh = −19→20
Absorption correction: multi-scan
(SADABS; Bruker, 2004)		k = −15→18
Tmin = 0.686, Tmax = 0.746l = −25→25
27602 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.130H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0661P)2 + 16.6643P]
where P = (Fo2 + 2Fc2)/3
5022 reflections(Δ/σ)max < 0.001
241 parametersΔρmax = 1.51 e Å−3
0 restraintsΔρmin = −1.57 e Å−3
Crystal data top
[Cu(C7H2Br3O2)(C19H17P)2]V = 4032.4 (4) Å3
Mr = 973.95Z = 4
Monoclinic, C2/cMo Kα radiation
a = 15.4522 (8) ŵ = 3.63 mm−1
b = 13.9073 (8) ÅT = 100 K
c = 19.3269 (10) Å0.18 × 0.09 × 0.06 mm
β = 103.862 (3)°
Data collection top
Bruker X8 APEXII 4K Kappa CCD
diffractometer		5022 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2004)		3970 reflections with I > 2σ(I)
Tmin = 0.686, Tmax = 0.746Rint = 0.053
27602 measured reflectionsθmax = 28.4°
Refinement top
R[F2 > 2σ(F2)] = 0.044 w = 1/[σ2(Fo2) + (0.0661P)2 + 16.6643P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.130Δρmax = 1.51 e Å−3
S = 1.04Δρmin = −1.57 e Å−3
5022 reflectionsAbsolute structure: ?
241 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
H-atom parameters constrained
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
xyzUiso*/Ueq
C20.5382 (2)0.6353 (3)0.28258 (18)0.0213 (7)
C30.5717 (2)0.7199 (3)0.32159 (19)0.0230 (7)
C40.5556 (2)0.8171 (3)0.3086 (2)0.0294 (8)
H40.58670.85960.34460.035*
C50.50.8599 (3)0.250.0295 (12)
C1110.3102 (2)0.3211 (3)0.25441 (19)0.0242 (7)
C1120.2526 (2)0.3880 (3)0.2148 (2)0.0309 (8)
H1120.26620.45460.22020.037*
C1130.1744 (3)0.3578 (4)0.1667 (2)0.0373 (10)
H1130.13390.40410.14110.045*
C1140.1562 (3)0.2615 (4)0.1565 (2)0.0375 (10)
H1140.10410.24110.12270.045*
C1150.2132 (3)0.1946 (3)0.1954 (2)0.0384 (10)
H1150.20030.1280.18830.046*
C1160.2898 (2)0.2235 (3)0.2451 (2)0.0310 (8)
H1160.32810.17690.27250.037*
C1210.4606 (2)0.2639 (2)0.36831 (19)0.0221 (7)
C1220.5385 (3)0.2234 (3)0.3588 (2)0.0317 (8)
H1220.56450.24720.32230.038*
C1230.5799 (3)0.1478 (3)0.4021 (3)0.0432 (11)
H1230.63340.12050.39490.052*
C1240.5423 (3)0.1126 (3)0.4559 (2)0.0412 (10)
H1240.570.06130.48560.049*
C1250.4650 (3)0.1526 (3)0.4655 (3)0.0470 (12)
H1250.43940.12920.50230.056*
C1260.4237 (3)0.2272 (3)0.4219 (3)0.0391 (10)
H1260.36970.25350.42880.047*
C1310.3738 (2)0.4421 (2)0.37497 (17)0.0202 (7)
C1320.2920 (2)0.4256 (3)0.39248 (19)0.0236 (7)
H1320.25250.37780.36770.028*
C1330.2690 (2)0.4791 (3)0.4460 (2)0.0277 (8)
H1330.21380.46670.45790.033*
C1340.3244 (3)0.5498 (3)0.4823 (2)0.0303 (8)
C1350.4049 (2)0.5684 (3)0.46311 (19)0.0263 (7)
H1350.4430.61830.48640.032*
C1360.4292 (2)0.5143 (3)0.41023 (18)0.0222 (7)
H1360.48410.5270.39810.027*
C1370.3016 (3)0.6032 (4)0.5422 (3)0.0512 (13)
H13A0.34850.65020.56120.077*
H13B0.29640.55790.57980.077*
H13C0.24470.63680.52490.077*
O20.56859 (15)0.55420 (17)0.30362 (13)0.0227 (5)
P10.41329 (5)0.36611 (6)0.31230 (5)0.01920 (18)
Cu10.50.43613 (4)0.250.01987 (15)
Br10.65536 (3)0.69166 (3)0.40942 (2)0.03295 (13)
Br20.50.99600 (5)0.250.0638 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C20.0140 (14)0.0293 (18)0.0231 (17)−0.0008 (13)0.0096 (13)0.0021 (14)
C30.0171 (14)0.0279 (18)0.0259 (17)−0.0019 (13)0.0090 (13)−0.0002 (14)
C40.0225 (17)0.0277 (19)0.041 (2)−0.0066 (14)0.0132 (15)−0.0078 (16)
C50.027 (2)0.011 (2)0.054 (3)00.016 (2)0
C1110.0150 (14)0.036 (2)0.0230 (17)−0.0030 (14)0.0071 (12)−0.0048 (15)
C1120.0273 (18)0.037 (2)0.0276 (19)−0.0005 (16)0.0047 (15)−0.0003 (16)
C1130.0256 (19)0.061 (3)0.0243 (19)0.0036 (18)0.0034 (15)0.0005 (18)
C1140.0222 (17)0.062 (3)0.030 (2)−0.0106 (18)0.0086 (15)−0.015 (2)
C1150.030 (2)0.047 (3)0.041 (2)−0.0167 (18)0.0150 (18)−0.017 (2)
C1160.0234 (17)0.036 (2)0.036 (2)−0.0069 (15)0.0102 (15)−0.0061 (17)
C1210.0212 (15)0.0196 (17)0.0260 (17)0.0014 (13)0.0070 (13)−0.0005 (13)
C1220.0262 (18)0.036 (2)0.036 (2)0.0055 (16)0.0138 (16)0.0070 (17)
C1230.034 (2)0.044 (3)0.055 (3)0.0189 (19)0.018 (2)0.018 (2)
C1240.045 (2)0.034 (2)0.047 (2)0.0110 (19)0.015 (2)0.0116 (19)
C1250.054 (3)0.040 (2)0.057 (3)0.013 (2)0.034 (2)0.021 (2)
C1260.035 (2)0.036 (2)0.055 (3)0.0110 (17)0.027 (2)0.015 (2)
C1310.0173 (14)0.0229 (17)0.0209 (16)0.0055 (13)0.0057 (12)0.0038 (13)
C1320.0178 (15)0.0269 (17)0.0273 (18)0.0018 (13)0.0076 (13)0.0003 (14)
C1330.0203 (16)0.037 (2)0.0273 (18)0.0075 (15)0.0077 (14)0.0022 (15)
C1340.0307 (18)0.036 (2)0.0238 (18)0.0155 (16)0.0051 (14)−0.0003 (16)
C1350.0262 (17)0.0257 (18)0.0227 (17)0.0044 (14)−0.0026 (13)0.0007 (14)
C1360.0176 (14)0.0236 (17)0.0239 (17)0.0037 (13)0.0021 (12)0.0024 (13)
C1370.045 (3)0.070 (3)0.039 (2)0.012 (2)0.010 (2)−0.018 (2)
O20.0171 (11)0.0233 (13)0.0272 (12)−0.0008 (9)0.0041 (9)0.0014 (10)
P10.0145 (4)0.0208 (4)0.0234 (4)−0.0004 (3)0.0068 (3)−0.0008 (3)
Cu10.0149 (3)0.0214 (3)0.0249 (3)00.0078 (2)0
Br10.0317 (2)0.0367 (2)0.0276 (2)−0.00878 (16)0.00144 (15)−0.00242 (16)
Br20.0539 (4)0.0268 (3)0.1064 (7)00.0112 (4)0
Geometric parameters (Å, º) top
C2—O21.252 (4)C123—C1241.396 (6)
C2—C31.426 (5)C123—H1230.95
C2—C2i1.506 (6)C124—C1251.370 (6)
C3—C41.387 (5)C124—H1240.95
C3—Br11.911 (4)C125—C1261.391 (6)
C4—C51.382 (5)C125—H1250.95
C4—H40.95C126—H1260.95
C5—C4i1.382 (5)C131—C1361.388 (5)
C5—Br21.893 (5)C131—C1321.403 (4)
C111—C1121.384 (5)C131—P11.820 (3)
C111—C1161.395 (5)C132—C1331.387 (5)
C111—P11.824 (3)C132—H1320.95
C112—C1131.400 (5)C133—C1341.381 (6)
C112—H1120.95C133—H1330.95
C113—C1141.375 (7)C134—C1351.405 (5)
C113—H1130.95C134—C1371.486 (6)
C114—C1151.374 (7)C135—C1361.391 (5)
C114—H1140.95C135—H1350.95
C115—C1161.392 (6)C136—H1360.95
C115—H1150.95C137—H13A0.98
C116—H1160.95C137—H13B0.98
C121—C1221.381 (5)C137—H13C0.98
C121—C1261.393 (5)O2—Cu12.090 (2)
C121—P11.830 (4)P1—Cu12.2284 (9)
C122—C1231.398 (6)Cu1—O2i2.090 (2)
C122—H1220.95Cu1—P1i2.2284 (9)
O2—C2—C3120.7 (3)C124—C125—H125119.7
O2—C2—C2i115.45 (19)C126—C125—H125119.7
C3—C2—C2i123.7 (2)C125—C126—C121120.9 (4)
C4—C3—C2133.0 (3)C125—C126—H126119.5
C4—C3—Br1114.5 (3)C121—C126—H126119.5
C2—C3—Br1112.5 (3)C136—C131—C132119.0 (3)
C5—C4—C3128.1 (4)C136—C131—P1118.8 (2)
C5—C4—H4115.9C132—C131—P1122.0 (3)
C3—C4—H4115.9C133—C132—C131119.9 (3)
C4i—C5—C4129.0 (5)C133—C132—H132120.1
C4i—C5—Br2115.5 (2)C131—C132—H132120.1
C4—C5—Br2115.5 (2)C134—C133—C132121.5 (3)
C112—C111—C116119.1 (3)C134—C133—H133119.2
C112—C111—P1117.4 (3)C132—C133—H133119.2
C116—C111—P1123.4 (3)C133—C134—C135118.5 (3)
C111—C112—C113120.2 (4)C133—C134—C137121.2 (4)
C111—C112—H112119.9C135—C134—C137120.3 (4)
C113—C112—H112119.9C136—C135—C134120.4 (3)
C114—C113—C112120.2 (4)C136—C135—H135119.8
C114—C113—H113119.9C134—C135—H135119.8
C112—C113—H113119.9C131—C136—C135120.6 (3)
C113—C114—C115119.9 (4)C131—C136—H136119.7
C113—C114—H114120.1C135—C136—H136119.7
C115—C114—H114120.1C134—C137—H13A109.5
C114—C115—C116120.6 (4)C134—C137—H13B109.5
C114—C115—H115119.7H13A—C137—H13B109.5
C116—C115—H115119.7C134—C137—H13C109.5
C115—C116—C111119.9 (4)H13A—C137—H13C109.5
C115—C116—H116120.1H13B—C137—H13C109.5
C111—C116—H116120.1C2—O2—Cu1116.1 (2)
C122—C121—C126118.3 (3)C131—P1—C111102.98 (15)
C122—C121—P1118.4 (3)C131—P1—C121101.98 (16)
C126—C121—P1123.2 (3)C111—P1—C121105.21 (17)
C121—C122—C123121.0 (4)C131—P1—Cu1116.55 (12)
C121—C122—H122119.5C111—P1—Cu1111.62 (12)
C123—C122—H122119.5C121—P1—Cu1116.91 (11)
C122—C123—C124119.9 (4)O2—Cu1—O2i76.42 (13)
C122—C123—H123120.1O2—Cu1—P1112.00 (7)
C124—C123—H123120.1O2i—Cu1—P1108.19 (7)
C125—C124—C123119.3 (4)O2—Cu1—P1i108.19 (7)
C125—C124—H124120.3O2i—Cu1—P1i112.00 (7)
C123—C124—H124120.3P1—Cu1—P1i128.18 (5)
C124—C125—C126120.6 (4)
O2—C2—C3—C4174.7 (4)C134—C135—C136—C1310.9 (5)
C2i—C2—C3—C4−9.2 (7)C3—C2—O2—Cu1171.0 (2)
O2—C2—C3—Br1−5.6 (4)C2i—C2—O2—Cu1−5.4 (4)
C2i—C2—C3—Br1170.5 (3)C136—C131—P1—C111−157.1 (3)
C2—C3—C4—C5−1.1 (6)C132—C131—P1—C11127.6 (3)
Br1—C3—C4—C5179.2 (2)C136—C131—P1—C12194.0 (3)
C3—C4—C5—C4i2.7 (3)C132—C131—P1—C121−81.3 (3)
C3—C4—C5—Br2−177.3 (3)C136—C131—P1—Cu1−34.5 (3)
C116—C111—C112—C1130.9 (5)C132—C131—P1—Cu1150.1 (2)
P1—C111—C112—C113176.9 (3)C112—C111—P1—C13162.6 (3)
C111—C112—C113—C114−2.6 (6)C116—C111—P1—C131−121.6 (3)
C112—C113—C114—C1152.2 (6)C112—C111—P1—C121169.0 (3)
C113—C114—C115—C116−0.1 (6)C116—C111—P1—C121−15.1 (3)
C114—C115—C116—C111−1.6 (6)C112—C111—P1—Cu1−63.2 (3)
C112—C111—C116—C1151.2 (5)C116—C111—P1—Cu1112.6 (3)
P1—C111—C116—C115−174.6 (3)C122—C121—P1—C131−141.0 (3)
C126—C121—C122—C123−0.4 (6)C126—C121—P1—C13136.4 (4)
P1—C121—C122—C123177.2 (4)C122—C121—P1—C111111.8 (3)
C121—C122—C123—C124−0.2 (7)C126—C121—P1—C111−70.8 (4)
C122—C123—C124—C1250.1 (8)C122—C121—P1—Cu1−12.7 (3)
C123—C124—C125—C1260.4 (8)C126—C121—P1—Cu1164.8 (3)
C124—C125—C126—C121−1.0 (8)C2—O2—Cu1—O2i2.14 (18)
C122—C121—C126—C1250.9 (7)C2—O2—Cu1—P1−102.3 (2)
P1—C121—C126—C125−176.5 (4)C2—O2—Cu1—P1i111.2 (2)
C136—C131—C132—C133−2.1 (5)C131—P1—Cu1—O226.45 (14)
P1—C131—C132—C133173.3 (3)C111—P1—Cu1—O2144.35 (15)
C131—C132—C133—C1340.8 (6)C121—P1—Cu1—O2−94.47 (15)
C132—C133—C134—C1351.3 (6)C131—P1—Cu1—O2i−55.86 (14)
C132—C133—C134—C137−176.7 (4)C111—P1—Cu1—O2i62.04 (15)
C133—C134—C135—C136−2.1 (5)C121—P1—Cu1—O2i−176.78 (14)
C137—C134—C135—C136175.8 (4)C131—P1—Cu1—P1i164.68 (12)
C132—C131—C136—C1351.2 (5)C111—P1—Cu1—P1i−77.41 (13)
P1—C131—C136—C135−174.3 (3)C121—P1—Cu1—P1i43.76 (13)
Symmetry code: (i) −x+1, y, −z+1/2.
Hydrogen-bond geometry (Å, º) top
Cg2 and Cg3 are the centroids of the C121–C126 and C131–C136 rings, respectively.
D—H···AD—HH···AD···AD—H···A
C136—H136···O20.952.523.365 (4)149
C115—H115···Cg3ii0.952.863.621 (4)138
C137—H13A···Cg2iii0.983.184.144 (6)168
Symmetry codes: (ii) x−1/2, y−1/2, z; (iii) x, −y+1, z+1/2.
Hydrogen-bond geometry (Å, º) top
Cg2 and Cg3 are the centroids of the C121–C126 and C131–C136 rings, respectively.
D—H···AD—HH···AD···AD—H···A
C136—H136···O20.952.523.365 (4)149
C115—H115···Cg3i0.952.863.621 (4)138.1
C137—H13A···Cg2ii0.983.184.144 (6)167.6
Symmetry codes: (i) x−1/2, y−1/2, z; (ii) x, −y+1, z+1/2.
Acknowledgements top

Professors G. Steyland and A. Roodt, University of the Free State, and Mr Renier Koen thanked for the data collection. Financial assistance from the University of the Free State Strategic Academic Cluster Initiative, SASOL, the South African NationalResearch Foundation (SA–NRF/THRIP) and the Inkaba yeAfrika Research Initiative is gratefully acknowledged. Part of this material is based on work supported by the SA–NRF/THRIP under grant No. GUN 2068915. Opinions, findings,conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the SA–NRF.

references
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