supplementary materials


is5304 scheme

Acta Cryst. (2013). E69, m574    [ doi:10.1107/S1600536813026573 ]

Bis[[mu]-3,5-bis­(pyridin-2-yl)-1H-pyrazole]­bis­[di­bromido­iron(III)]

N. Katsuta, A. Mishima, A. Fuyuhiro, S. Hayami and S. Kawata

Abstract top

The title dinuclear complex, [Fe2Br4(C13H9N4)2], which lies on an inversion center, features two approximately planar bis­(pyridin-2-yl)pyrazole (bpypz-) ligands [maximum deviation = 0.082 (3) Å] and four bromide ions. Each FeIII ion is octa­hedrally coordinated by four N atoms of two bpypz- ligands and two Br ions. [pi]-[pi] stacking inter­actions [centroid-centroid distances = 3.7004 (17)-4.0123 (18) Å] are observed between pyridyl and pyrazole rings, and between pyridyl and pyridyl rings of adjacent complex mol­ecules.

Comment top

3,5-Bis(pyridin-2-yl)pyrazole[Hbpypz] is a versatile ligand in the construction of a series of mononuclear, dinuclear and polynuclear complexes (Yoneda, Adachi, Hayami et al., 2006; Yoneda, Adachi, Nishio et al., 2006; Ishikawa et al., 2010). The dinuclear complexes show the structure where two bpypz- ions are bridging two metal ions with the axial coordination sites. This kind of dinuclear complexes with transition metal ions were reported previously (Mishima et al., 2011; Washizaki et al., 2012). We have succeeded in synthesizing the title compound that contains iron(III) ion for the first time. To the best of our knowledge, similar compounds with the only iron(II) ions in it (Yoneda, Adachi, Hayami et al., 2006; Yoneda, Adachi, Nishio et al., 2006). In the dinuclear complex, four N donors from two deprotonated tetrahedral bridging bpypz- ligands make an equatorial plane (Table 1). The iron(III) ions are six-coordinated and the axial positions are occupied by bromide ions. From the Mössbauer measurement, the valence of all iron ions is trivalent. There are ππ stacking interactions between pyridyl and pyrazole rings and between pyridyl and pyridyl rings [centroid-centroid distances 3.7004 (17) Å, 4.0123 (18) Å and 4.0022 (18) Å] to form a three-dimensional structure.

Related literature top

For metal complexes of 3,5-bis(pyridin-2-yl)pyrazole, see: Yoneda, Adachi, Hayami et al. (2006); Yoneda, Adachi, Nishio et al. (2006); Ishikawa et al. (2010); Mishima et al. (2011); Washizaki et al. (2012).

Experimental top

A methanolic solution of FeBr3 (5 ml, 5 mmolL-1) was transferred to a glass tube, and methanolic solution of Hbpypz (5 ml, 5 mmolL-1) was poured into the glass tube without mixing the solutions. Black crystals began to form at ambient temperature within one week (yield 58%). Element analysis: calcd (%) for C26H18Fe2N8Br4: C 35.74, H 2.08, N 12.83; found; C 35.97, H 2.26, N 12.67.

Refinement top

The C-bound hydrogen atoms in the bpypz- ion were placed at calculated positions (C—H = 0.95 Å) and were treated as riding on their parent atoms with Uiso(H) set to 1.2Ueq(C).

Computing details top

Data collection: CrystalClear (Rigaku, 2008); cell refinement: CrystalClear (Rigaku, 2008); data reduction: CrystalClear (Rigaku, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); 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. An ORTEP drawing of the title complex, showing 50% probability displacement elipsoids.
[Figure 2] Fig. 2. A packing diagram of the title compound, viewed along the b axis.
Bis[µ-3,5-bis(pyridin-2-yl)-1H-pyrazole]bis[dibromidoiron(III)] top
Crystal data top
[Fe2(C13H9N4)2Br4]F(000) = 1688.00
Mr = 873.79Dx = 2.047 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71075 Å
Hall symbol: -C 2ycCell parameters from 3978 reflections
a = 18.180 (4) Åθ = 3.1–27.5°
b = 14.857 (3) ŵ = 6.71 mm1
c = 10.530 (3) ÅT = 110 K
β = 94.646 (3)°Block, black
V = 2834.7 (10) Å30.10 × 0.10 × 0.10 mm
Z = 4
Data collection top
Rigaku Saturn724
diffractometer
2730 reflections with F2 > 2σ(F2)
Detector resolution: 7.111 pixels mm-1Rint = 0.031
ω scansθmax = 27.5°
Absorption correction: multi-scan
(REQAB; Rigaku, 1998)
h = 2323
Tmin = 0.408, Tmax = 0.511k = 1918
16288 measured reflectionsl = 1313
3246 independent reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.023Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.060H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0344P)2]
where P = (Fo2 + 2Fc2)/3
3246 reflections(Δ/σ)max = 0.001
181 parametersΔρmax = 0.70 e Å3
0 restraintsΔρmin = 0.46 e Å3
Primary atom site location: structure-invariant direct methods
Crystal data top
[Fe2(C13H9N4)2Br4]V = 2834.7 (10) Å3
Mr = 873.79Z = 4
Monoclinic, C2/cMo Kα radiation
a = 18.180 (4) ŵ = 6.71 mm1
b = 14.857 (3) ÅT = 110 K
c = 10.530 (3) Å0.10 × 0.10 × 0.10 mm
β = 94.646 (3)°
Data collection top
Rigaku Saturn724
diffractometer
3246 independent reflections
Absorption correction: multi-scan
(REQAB; Rigaku, 1998)
2730 reflections with F2 > 2σ(F2)
Tmin = 0.408, Tmax = 0.511Rint = 0.031
16288 measured reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.023H-atom parameters constrained
wR(F2) = 0.060Δρmax = 0.70 e Å3
S = 1.05Δρmin = 0.46 e Å3
3246 reflectionsAbsolute structure: ?
181 parametersAbsolute structure parameter: ?
0 restraintsRogers parameter: ?
Special details top

Geometry. ENTER SPECIAL DETAILS OF THE MOLECULAR GEOMETRY

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
Br10.443797 (14)0.261741 (15)0.48610 (2)0.01790 (7)
Br20.229060 (14)0.271406 (15)0.16980 (2)0.01985 (8)
Fe10.323234 (19)0.26281 (2)0.35150 (3)0.01290 (9)
N10.35940 (11)0.39427 (12)0.28651 (17)0.0132 (4)
N20.27110 (11)0.35166 (12)0.46615 (17)0.0127 (4)
N30.22342 (11)0.34385 (12)0.55761 (17)0.0129 (4)
N40.13421 (11)0.35514 (12)0.74213 (18)0.0142 (4)
C10.40369 (13)0.41136 (16)0.1936 (3)0.0170 (5)
C20.42317 (13)0.49806 (17)0.1611 (3)0.0189 (6)
C30.39704 (14)0.56992 (16)0.2285 (3)0.0183 (5)
C40.35166 (13)0.55314 (16)0.3250 (3)0.0162 (5)
C50.33295 (12)0.46438 (15)0.3509 (2)0.0125 (5)
C60.28327 (13)0.44061 (14)0.4473 (2)0.0115 (5)
C70.24257 (12)0.49193 (15)0.5276 (2)0.0133 (5)
C80.20575 (12)0.42818 (14)0.5948 (2)0.0116 (5)
C90.15481 (12)0.43495 (15)0.6951 (2)0.0122 (5)
C100.13052 (13)0.51621 (15)0.7420 (3)0.0149 (5)
C110.08420 (13)0.51551 (16)0.8403 (3)0.0181 (6)
C120.06344 (14)0.43331 (16)0.8892 (3)0.0186 (5)
C130.08932 (14)0.35518 (16)0.8374 (3)0.0186 (6)
H10.42240.36220.14840.0204*
H20.45390.50810.09360.0227*
H30.41020.62990.20870.0220*
H40.33350.60130.37290.0195*
H50.24060.55560.53470.0160*
H60.14550.57160.70700.0179*
H70.06700.57030.87370.0218*
H80.03200.43090.95690.0223*
H90.07480.29910.87060.0224*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.01636 (13)0.01757 (13)0.02030 (13)0.00300 (9)0.00476 (9)0.00269 (9)
Br20.02435 (15)0.01322 (13)0.02169 (14)0.00149 (10)0.00004 (10)0.00022 (9)
Fe10.01458 (18)0.00915 (17)0.01610 (17)0.00004 (13)0.00820 (13)0.00050 (12)
N10.0134 (10)0.0127 (10)0.0140 (10)0.0010 (8)0.0045 (8)0.0016 (8)
N20.0145 (10)0.0101 (9)0.0147 (10)0.0001 (8)0.0079 (8)0.0001 (8)
N30.0127 (10)0.0106 (10)0.0163 (10)0.0013 (8)0.0067 (8)0.0006 (8)
N40.0158 (11)0.0105 (9)0.0172 (10)0.0010 (8)0.0066 (8)0.0020 (8)
C10.0157 (13)0.0196 (13)0.0164 (12)0.0010 (10)0.0055 (10)0.0006 (10)
C20.0122 (12)0.0284 (14)0.0166 (12)0.0046 (11)0.0033 (10)0.0067 (11)
C30.0185 (13)0.0155 (12)0.0210 (13)0.0039 (10)0.0010 (11)0.0075 (10)
C40.0167 (13)0.0126 (12)0.0194 (13)0.0008 (10)0.0013 (10)0.0021 (10)
C50.0121 (12)0.0124 (12)0.0132 (12)0.0008 (9)0.0011 (9)0.0021 (9)
C60.0102 (12)0.0097 (11)0.0144 (11)0.0002 (9)0.0005 (9)0.0001 (9)
C70.0141 (12)0.0100 (11)0.0157 (12)0.0010 (9)0.0005 (10)0.0003 (9)
C80.0105 (12)0.0095 (11)0.0148 (11)0.0016 (9)0.0022 (9)0.0022 (9)
C90.0088 (11)0.0133 (11)0.0146 (11)0.0010 (9)0.0016 (9)0.0010 (9)
C100.0141 (12)0.0127 (11)0.0182 (12)0.0007 (10)0.0026 (10)0.0022 (9)
C110.0150 (13)0.0178 (13)0.0219 (13)0.0028 (10)0.0032 (10)0.0070 (10)
C120.0159 (13)0.0223 (13)0.0189 (12)0.0017 (10)0.0092 (10)0.0026 (10)
C130.0196 (13)0.0158 (12)0.0217 (13)0.0011 (10)0.0089 (11)0.0008 (10)
Geometric parameters (Å, º) top
Br1—Fe12.5119 (6)C5—C61.456 (4)
Br2—Fe12.4652 (6)C6—C71.395 (4)
Fe1—N12.1882 (19)C7—C81.386 (4)
Fe1—N22.070 (2)C8—C91.464 (4)
Fe1—N3i2.0683 (19)C9—C101.390 (4)
Fe1—N4i2.183 (2)C10—C111.387 (4)
N1—C11.340 (4)C11—C121.389 (4)
N1—C51.352 (3)C12—C131.381 (4)
N2—N31.352 (3)C1—H10.950
N2—C61.357 (3)C2—H20.950
N3—C81.359 (3)C3—H30.950
N4—C91.350 (3)C4—H40.950
N4—C131.344 (4)C7—H50.950
C1—C21.386 (4)C10—H60.950
C2—C31.387 (4)C11—H70.950
C3—C41.382 (4)C12—H80.950
C4—C51.394 (4)C13—H90.950
N1···C32.778 (3)Br1···H7viii3.2176
N2···N2i3.211 (3)Br1···H8ix3.3070
N2···C93.555 (3)Br1···H9ix2.9039
N3···N3i3.221 (3)Br2···H4ii2.7927
N3···C53.552 (3)Br2···H5iii2.9531
N4···C112.779 (3)Br2···H6iii2.8284
C1···C42.731 (4)N1···H5iii3.3653
C2···C52.732 (4)N2···H3vi3.4557
C4···C73.162 (4)N2···H6iii3.5987
C7···C103.181 (4)N3···H7iii3.5460
C9···C122.736 (4)C1···H1iv3.5269
C10···C132.723 (4)C1···H2iv3.5841
Br2···C4ii3.562 (3)C1···H4iii3.5173
C1···C7iii3.587 (4)C1···H5iii3.3217
C2···C2iv3.235 (4)C2···H2iv3.2792
C2···C3iv3.544 (4)C2···H5iii3.5654
C2···C5iii3.578 (4)C3···H2iv3.2970
C2···C6iii3.382 (4)C4···H2vi3.3814
C2···C7iii3.468 (4)C5···H2vi3.2600
C3···C2iv3.544 (4)C6···H2vi3.4358
C3···C6iii3.476 (4)C6···H6iii3.4177
C3···C7iii3.499 (4)C7···H7iii3.5827
C4···Br2v3.562 (3)C8···H7iii3.2916
C4···C8iii3.456 (4)C10···H8iii3.4589
C5···C2vi3.578 (4)C11···H5vi3.5274
C6···C2vi3.382 (4)C11···H7vii3.5058
C6···C3vi3.476 (4)C11···H8x3.2231
C6···C10iii3.438 (4)C12···H5vi3.4559
C7···C1vi3.587 (4)C12···H6vi3.5530
C7···C2vi3.468 (4)C12···H7x3.5799
C7···C3vi3.499 (4)C12···H8x3.1884
C7···C10iii3.496 (4)C13···H5vi3.5645
C7···C11iii3.357 (4)H1···Br1iv3.2719
C8···C4vi3.456 (4)H1···C1iv3.5269
C8···C11iii3.436 (4)H1···H1iv3.3987
C10···C6vi3.438 (4)H1···H4iii3.2504
C10···C7vi3.496 (4)H2···C1iv3.5841
C11···C7vi3.357 (4)H2···C2iv3.2792
C11···C8vi3.436 (4)H2···C3iv3.2970
C11···C11vii3.471 (4)H2···C4iii3.3814
C12···C12vii3.580 (4)H2···C5iii3.2600
Fe1···H13.2605H2···C6iii3.4358
Fe1···H9i3.2336H2···H2iv3.5717
N1···H23.2407H2···H2xi2.7001
N1···H43.2527H2···H3iv3.5888
N1···H9i3.5694H2···H4iii3.4658
N2···H53.1742H3···Br1iii2.9480
N3···H53.1726H3···N2iii3.4557
N4···H63.2453H3···H2iv3.5888
N4···H83.2424H3···H3iv3.3113
C1···H33.2521H4···Br2v2.7927
C1···H9i3.2291H4···C1vi3.5173
C2···H43.2519H4···H1vi3.2504
C3···H13.2422H4···H2vi3.4658
C4···H23.2513H5···Br2vi2.9531
C4···H53.1113H5···N1vi3.3653
C5···H13.1713H5···C1vi3.3217
C5···H33.2556H5···C2vi3.5654
C5···H52.9888H5···C11iii3.5274
C6···H42.6951H5···C12iii3.4559
C7···H42.9097H5···C13iii3.5645
C7···H62.9367H6···Br2vi2.8284
C8···H62.7104H6···N2vi3.5987
C9···H52.9872H6···C6vi3.4177
C9···H73.2585H6···C12iii3.5530
C9···H93.1692H6···H8iii3.2113
C10···H53.1329H7···Br1xii3.2176
C10···H83.2546H7···N3vi3.5460
C11···H93.2375H7···C7vi3.5827
C12···H63.2537H7···C8vi3.2916
C13···H1i3.2409H7···C11vii3.5058
C13···H73.2484H7···C12x3.5799
H1···H22.3264H7···H7vii3.4188
H1···H9i2.4051H7···H8x2.6342
H2···H32.3513H8···Br1xiii3.3070
H3···H42.3459H8···C10vi3.4589
H4···H52.5858H8···C11x3.2231
H5···H62.6162H8···C12x3.1884
H6···H72.3505H8···H6vi3.2113
H7···H82.3563H8···H7x2.6342
H8···H92.3194H8···H8x2.5629
Br1···H1iv3.2719H9···Br1xiii2.9039
Br1···H3vi2.9480H9···H9vii3.5667
Br1—Fe1—Br2163.258 (18)C4—C5—C6122.7 (2)
Br1—Fe1—N184.93 (5)N2—C6—C5117.1 (2)
Br1—Fe1—N295.44 (6)N2—C6—C7110.0 (2)
Br1—Fe1—N3i96.08 (6)C5—C6—C7132.8 (2)
Br1—Fe1—N4i85.69 (6)C6—C7—C8103.8 (2)
Br2—Fe1—N185.32 (5)N3—C8—C7110.3 (2)
Br2—Fe1—N295.60 (6)N3—C8—C9116.7 (2)
Br2—Fe1—N3i96.53 (6)C7—C8—C9132.9 (2)
Br2—Fe1—N4i86.58 (6)N4—C9—C8114.5 (2)
N1—Fe1—N277.09 (8)N4—C9—C10121.8 (3)
N1—Fe1—N3i166.76 (8)C8—C9—C10123.6 (2)
N1—Fe1—N4i116.67 (8)C9—C10—C11119.2 (3)
N2—Fe1—N3i89.68 (8)C10—C11—C12118.9 (3)
N2—Fe1—N4i166.23 (8)C11—C12—C13118.8 (3)
N3i—Fe1—N4i76.56 (8)N4—C13—C12122.8 (3)
Fe1—N1—C1127.64 (16)N1—C1—H1118.756
Fe1—N1—C5113.76 (15)C2—C1—H1118.757
C1—N1—C5118.6 (2)C1—C2—H2120.548
Fe1—N2—N3135.33 (14)C3—C2—H2120.549
Fe1—N2—C6116.60 (16)C2—C3—H3120.420
N3—N2—C6108.03 (18)C4—C3—H3120.433
Fe1i—N3—N2134.91 (14)C3—C4—H4120.531
Fe1i—N3—C8117.24 (16)C5—C4—H4120.537
N2—N3—C8107.84 (18)C6—C7—H5128.129
Fe1i—N4—C9114.88 (16)C8—C7—H5128.117
Fe1i—N4—C13126.62 (16)C9—C10—H6120.378
C9—N4—C13118.5 (2)C11—C10—H6120.397
N1—C1—C2122.5 (3)C10—C11—H7120.565
C1—C2—C3118.9 (3)C12—C11—H7120.574
C2—C3—C4119.1 (3)C11—C12—H8120.618
C3—C4—C5118.9 (3)C13—C12—H8120.606
N1—C5—C4121.9 (2)N4—C13—H9118.594
N1—C5—C6115.4 (2)C12—C13—H9118.589
Br1—Fe1—N1—C184.08 (14)Fe1—N2—N3—C8177.09 (13)
Br1—Fe1—N1—C595.49 (11)Fe1—N2—C6—C51.4 (3)
Br1—Fe1—N2—N399.09 (17)Fe1—N2—C6—C7177.79 (11)
Br1—Fe1—N2—C683.63 (12)N3—N2—C6—C5179.43 (16)
Br1—Fe1—N3i—N2i98.43 (16)N3—N2—C6—C70.2 (3)
Br1—Fe1—N3i—C8i83.02 (12)C6—N2—N3—Fe1i178.29 (16)
Br1—Fe1—N4i—C9i94.73 (12)C6—N2—N3—C80.4 (2)
Br1—Fe1—N4i—C13i83.63 (14)Fe1i—N3—C8—C7178.53 (11)
Br2—Fe1—N1—C182.30 (14)Fe1i—N3—C8—C90.5 (3)
Br2—Fe1—N1—C598.13 (11)N2—N3—C8—C70.4 (3)
Br2—Fe1—N2—N393.51 (17)N2—N3—C8—C9179.40 (16)
Br2—Fe1—N2—C683.77 (12)Fe1i—N4—C9—C83.6 (3)
Br2—Fe1—N3i—N2i92.60 (16)Fe1i—N4—C9—C10178.07 (13)
Br2—Fe1—N3i—C8i85.95 (12)Fe1i—N4—C13—C12178.31 (13)
Br2—Fe1—N4i—C9i100.13 (12)C9—N4—C13—C120.0 (4)
Br2—Fe1—N4i—C13i81.51 (14)C13—N4—C9—C8177.94 (18)
N1—Fe1—N2—N3177.39 (18)C13—N4—C9—C100.4 (3)
N1—Fe1—N2—C60.12 (12)N1—C1—C2—C31.2 (4)
N2—Fe1—N1—C1179.14 (16)C1—C2—C3—C40.8 (4)
N2—Fe1—N1—C51.29 (11)C2—C3—C4—C50.6 (4)
N1—Fe1—N4i—C9i176.84 (11)C3—C4—C5—N11.7 (4)
N1—Fe1—N4i—C13i1.51 (18)C3—C4—C5—C6177.58 (19)
N4i—Fe1—N1—C11.50 (17)N1—C5—C6—N22.6 (3)
N4i—Fe1—N1—C5178.07 (10)N1—C5—C6—C7176.4 (2)
N2—Fe1—N3i—N2i3.00 (17)C4—C5—C6—N2178.08 (19)
N2—Fe1—N3i—C8i178.45 (13)C4—C5—C6—C72.9 (4)
N3i—Fe1—N2—N33.02 (17)N2—C6—C7—C80.0 (3)
N3i—Fe1—N2—C6179.70 (13)C5—C6—C7—C8179.0 (3)
N3i—Fe1—N4i—C9i2.58 (12)C6—C7—C8—N30.3 (3)
N3i—Fe1—N4i—C13i179.07 (16)C6—C7—C8—C9179.0 (2)
N4i—Fe1—N3i—N2i177.49 (18)N3—C8—C9—N42.7 (3)
N4i—Fe1—N3i—C8i1.06 (12)N3—C8—C9—C10178.92 (17)
Fe1—N1—C1—C2179.70 (13)C7—C8—C9—N4176.0 (2)
Fe1—N1—C5—C4178.28 (13)C7—C8—C9—C102.3 (4)
Fe1—N1—C5—C62.4 (2)N4—C9—C10—C110.4 (4)
C1—N1—C5—C41.3 (3)C8—C9—C10—C11177.79 (18)
C1—N1—C5—C6177.99 (17)C9—C10—C11—C120.0 (4)
C5—N1—C1—C20.2 (3)C10—C11—C12—C130.4 (4)
Fe1—N2—N3—Fe1i4.3 (4)C11—C12—C13—N40.4 (4)
Symmetry codes: (i) x+1/2, y+1/2, z+1; (ii) x+1/2, y1/2, z+1/2; (iii) x, y+1, z1/2; (iv) x+1, y, z+1/2; (v) x+1/2, y+1/2, z+1/2; (vi) x, y+1, z+1/2; (vii) x, y, z+3/2; (viii) x+1/2, y1/2, z+3/2; (ix) x+1/2, y+1/2, z1/2; (x) x, y+1, z+2; (xi) x+1, y+1, z; (xii) x+1/2, y+1/2, z+3/2; (xiii) x1/2, y+1/2, z+1/2.
Selected bond lengths (Å) top
Br1—Fe12.5119 (6)Fe1—N22.070 (2)
Br2—Fe12.4652 (6)Fe1—N3i2.0683 (19)
Fe1—N12.1882 (19)Fe1—N4i2.183 (2)
Symmetry code: (i) x+1/2, y+1/2, z+1.
Acknowledgements top

This work was supported by the fund Grant-in-Aids for Science Research (No. 25410078) from the Ministry of Education, Culture, Sports, Science and Technology of Japan.

references
References top

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