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Logo of actae2this articlesearchopen accesssubmitActa Crystallographica Section E: Crystallographic CommunicationsActa Crystallographica Section E: Crystallographic Communications
 
Acta Crystallogr E Crystallogr Commun. 2017 October 1; 73(Pt 10): 1551–1554.
Published online 2017 September 29. doi:  10.1107/S2056989017013512
PMCID: PMC5730316

Crystal structure of fac-tri­carbonyl­chlorido­bis­(4-hy­droxy­pyridine)­rhenium(I)–pyridin-4(1H)-one (1/1)

Abstract

The asymmetric unit of the title compound, [ReCl(C5H5NO)2(CO)3]·C5H5NO, contains one mol­ecule of the complex fac-[ReCl(4-pyOH)2(CO)3] (where 4-pyOH represents 4-hy­droxy­pyridine) and one mol­ecule of pyridin-4(1H)-one (4-HpyO). In the mol­ecule of the complex, the Re atom is coordinated to two N atoms of the two 4-pyOH ligands, three carbonyl C atoms, in a facial configuration, and the Cl atom. The resulting geometry is slightly distorted octa­hedral. In the crystal structure, both fragments are associated by hydrogen bonds; two 4-HpyO mol­ecules bridge between two mol­ecules of the complex using the O=C group as acceptor for two different HO– groups of coordinated 4-pyOH from two neighbouring metal complexes. The resulting square arrangements are extented into infinite chains by hydrogen bonds involving the N—H groups of the 4-HpyO mol­ecule and the chloride ligands. The chains are further stabilized by π-stacking inter­actions.

Keywords: crystal structure, rhenium(I) compounds, 4-hy­droxy­pyridine, pyridin-4(1H)-one

Chemical context  

The structural stability of the fac-{ReI(CO)3} fragment and its trend to form sixfold coordinated octa­hedral complexes make it a suitable candidate for the construction of self-assambled metallomacrocycles, with some of them showing inter­esting properties (Slone et al., 1998  ; Sun & Lees, 2002  ). Bi­pyridine (and pyrazine) based ligands are usually chosen to obtain square or rectangular metallocycles, [Re4(L)4(CO)12] (L is the bridging ligand) with inter­nal diameters of 5–9 nm. In the present work, we present the structure of a rhenium complex, where the square architecture is achieved by a coordinative Re—L link (where L is 4-hy­droxy­pyridine) and by hydrogen-bonding inter­actions involving a 4-pyridone mol­ecule (a tautomer of 4-hy­droxy­pyridine L).

An external file that holds a picture, illustration, etc.
Object name is e-73-01551-scheme1.jpg

Structural commentary  

The crystal structure consists of mol­ecules of fac-[ReCl(4-pyOH)2(CO)3] (where 4-pyOH represents 4-hy­droxy­pyridine) and pyridin-4(1H)-one (4-HpyO) in a 1:1 ratio (Fig. 1  ). Both mol­ecules are associated through hydrogen bonding (see below). The existence of the pyridone form instead of hy­droxy­pyridine is confirmed by the C—O bond distance, subtanti­ally shorthened in 4-HpyO [C11—O3 = 1.293 (5) Å] with respect to the coordinated 4-pyOH [O1—C1 = 1.335 (5) Å and O2—C6 = 1.339 (5) Å], indicating the presence of a double C=O bond in 4-HpyO. The C—C bond lengths involving the carbonyl group [C11—C12 = 1.425 (6) Å and C11—C15 = 1.432 (6) Å] are elongated with respect to those observed in the 4-pyOH fragments [for instance, C1—C2 = 1.404 (6) Å and C1—C5 = 1.395 (6) Å]. The C—N bond lengths are also longer than their typical values in pyridines or pyridinium cations. These parameters are close to those found in the crystal structure of the free (uncoordinated) 4-pyridone (Jones, 2001  ; Tyl et al., 2008  ) or to those involved in hydrogen bonding (Campos-Gaxiola et al. 2014  ; Staun & Oliver, 2012  ; 2015  ).

Figure 1
The mol­ecular structure of the title compound, with displacement ellipsoids drawn at the 50% probability level.

The mol­ecular structure of fac-[ReCl(4-pyOH)2(CO)3] is similar to other tri­carbonyl­rhenium(I) complexes with two pyridine-based ligands (Abel & Wilkinson, 1959  ; Farrell et al., 2016  ). The coordination polyhedron around the Re atom can be described as slightly distorted octa­hedral (all angles are close to 90 or 180°), formed by coordination of the two N atoms of the two 4-pyOH ligands (N1 and N2), by the three carbonyl C atoms, in a facial configuration, and the chloride ligand. Both Re—N bond lengths [2.208 (4) and 2.210 (4) Å] are statistically equivalent. Neverthless, the Re—Cl bond in the present compound [2.4986 (10) Å] is longer that those found in pyridine derivatives described recently by Farrell et al. (2016  ), with an average value of 2.4649 (4) Å. This fact is likely due to the hydrogen-bonding inter­action involving the chloride and the N—H group of a neighbouring 4-pyridone since this inter­action is absent in those structures.

Supra­molecular features  

The mol­ecular association in the crystal is strongly directed by hydrogen bonding (Table 1  ). Two 4-pyridone mol­ecules bridge between two fac-[ReCl(4-pyOH)2(CO)3] using the ketone O=C group as the hydrogen-bonding acceptor to two different HO– groups, forming An external file that holds a picture, illustration, etc.
Object name is e-73-01551-efi1.jpg(28) rings centred at the g Wyckoff site (Fig. 2  ). The N—H group of the pyridone unit also establishes hydrogen-bond inter­actions, with the chloride group, yielding a new centrosymmetric ring An external file that holds a picture, illustration, etc.
Object name is e-73-01551-efi2.jpg(28) (at the f Wickoff site). Although the centroid-to-centroid distance between the pyridone and hy­droxy­pyridone is rather long (3.791 Å), some distances between the atoms and centroids of the rings [C4(...)N3vi = 3.231 Å, C4(...)C14vi = 3.470 Å, C5(...)C14vi = 3.478 Å and C5(...)Civi = 3.365 Å; symmetry code: (vi) 1 − x, 2 − y, 1 − z; see Fig. 2  ] suggest a (slipped) π-stacking inter­action. Both inter­molecular inter­actions work to form infinite chains, as represented in Fig. 2  , which are further supported by weak C—H(...)O and C—H(...)Cl inter­actions (the most representative ones are included in Table 1  ). The formation of the An external file that holds a picture, illustration, etc.
Object name is e-73-01551-efi1.jpg(28) rings yields a small channel-like void of ca 103 Å3 per unit cell, as shown in Fig. 3  . No substantial electron density is found in the channels (ca 4 electrons per void based on a PLATON/SQUEEZE analysis (Spek, 2009  , 2015  ).

Figure 2
Representation of the formation of chains by hydrogen-bonding and π-stacking in the crystal structure.
Figure 3
Association of the chains and formation of the empty channels in the crystal structure.
Table 1
Hydrogen-bond geometry (Å, °)

Database survey  

The structures of several complexes with the metal centre fac-tri­carbonyl­rhenium(I) and pyridine-based ligands have been reported (Abel & Wilkinson, 1959  ; Farrell et al., 2016  ). The pyridine fragment can be part of a bridging ligand between different metal centres to form tetra­nuclear complexes as reported by Levine et al. (2009  ). When ligands based on 4,4′-bi­pyridine are chosen, square (Slone et al., 1996  ; Bera et al., 2004  ; Sun et al., 2002  ) or rectangular (Dinolfo & Hupp, 2004  ; Gupta et al., 2011  ; Lu et al., 2012  ; Nagarajaprakash et al., 2014  ; Orsa et al., 2007  ) homo- or heteronuclear complexes are isolated. Applications of these compounds as sensors (Keefe et al., 2000  ), luminescent materials (Slone et al., 1996  ) or cytotoxic agents (Orsa et al., 2007  ) have been also reported.

Synthesis and crystallization  

The complex fac-[ReCl(4-pyOH)2(CO)3] was obtained by refluxing for 90 min a mixture of 4-hy­droxy­pyridine (29 mg, 0.31 mmol) and [ReCl(CH3CN)2(CO)3] in chloro­form–methanol (1:1 v/v, 10 ml). The solution was concentrated (to half of initial volume), diethyl ether was added and the mixture cooled to 277 K. Finally, the solid was filtered off and vacuum dried on CaCl2 (yield: 81%, 30 mg; m.p. 418–421 K). Analysis, calculated for C13H10ClN2O5Re: C 31.5, H 2.0, N 5.6%; found: C 31.9, H 1.9, N 5.5%. MS–ESI [m/z (%)]: 461 (100) [M – Cl]+. IR (ATR, cm−1): 2016 (m), 1865 (b, s), ν(CO).

Single crystals of the title compound (too few for elemental analysis or meaningful estimation of the yield) were obtained from solutions of fac-[ReCl(CO)3(4-pyOH)2] in CHCl3:CH2Cl2:ether (1:1:1) stored at 253 K (several days).

Refinement  

Crystal data, data collection and structure refinement details are summarized in Table 2  . H atoms on O and N atoms were located via difference Fourier analyses and refined with U iso(H) = 1.5U eq(O) and 1.2U eq(N). Other H atoms were included at calculated sites and allowed to ride on their carrier atoms, with U iso(H) = 1.2U eq(C).

Table 2
Experimental details

Supplementary Material

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S2056989017013512/zl2716sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989017013512/zl2716Isup2.hkl

CCDC reference: 1575682

Additional supporting information: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Crystal data

[ReCl(C5H5NO)2(CO)3]·C5H5NOF(000) = 568
Mr = 590.98Dx = 1.818 Mg m3
Triclinic, P1Melting point: 145 K
a = 7.5235 (13) ÅMo Kα radiation, λ = 0.71073 Å
b = 11.717 (2) ÅCell parameters from 9858 reflections
c = 13.644 (2) Åθ = 3.3–26.6°
α = 66.694 (4)°µ = 5.79 mm1
β = 78.757 (4)°T = 100 K
γ = 81.374 (4)°Plate, yellow
V = 1079.9 (3) Å30.36 × 0.35 × 0.04 mm
Z = 2

Data collection

Bruker D8 Venture Photon 100 CMOS diffractometer4312 reflections with I > 2σ(I)
[var phi] and ω scansRint = 0.041
Absorption correction: multi-scan (SADABS; Krause et al., 2015)θmax = 26.6°, θmin = 2.8°
Tmin = 0.352, Tmax = 0.647h = −9→9
28225 measured reflectionsk = −14→14
4476 independent reflectionsl = −17→17

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.029H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.077w = 1/[σ2(Fo2) + (0.0178P)2 + 5.8451P] where P = (Fo2 + 2Fc2)/3
S = 1.35(Δ/σ)max = 0.001
4476 reflectionsΔρmax = 1.63 e Å3
272 parametersΔρmin = −1.03 e Å3
0 restraintsExtinction correction: SHELXL2013 (Sheldrick, 2015b), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0119 (9)

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 (Å2)

xyzUiso*/Ueq
Re10.86373 (2)0.70746 (2)0.07222 (2)0.01123 (10)
Cl11.09377 (15)0.82393 (10)0.09609 (9)0.0135 (2)
O10.3391 (5)0.8384 (4)0.4444 (3)0.0208 (8)
H10.394 (10)0.843 (6)0.499 (6)0.031*
O21.1814 (5)0.2036 (3)0.4087 (3)0.0229 (8)
O30.4725 (5)0.8444 (3)0.6006 (3)0.0203 (8)
H21.319 (10)0.196 (6)0.399 (6)0.030*
O201.1184 (5)0.6629 (4)−0.1173 (3)0.0232 (8)
O210.6852 (5)0.9364 (4)−0.0929 (3)0.0243 (8)
O220.5800 (6)0.5598 (4)0.0526 (4)0.0299 (9)
N10.6881 (5)0.7397 (4)0.2102 (3)0.0129 (8)
N20.9814 (5)0.5408 (4)0.1954 (3)0.0138 (8)
N30.1310 (6)0.9766 (4)0.8090 (4)0.0225 (9)
H3A0.056 (9)1.011 (6)0.859 (6)0.027*
C10.4552 (7)0.8016 (4)0.3733 (4)0.0154 (9)
C20.3875 (7)0.7932 (5)0.2880 (4)0.0165 (10)
H2A0.26070.80720.28480.020*
C30.5057 (7)0.7646 (4)0.2088 (4)0.0151 (9)
H30.45770.76210.15030.018*
C40.7506 (7)0.7409 (4)0.2958 (4)0.0140 (9)
H40.87670.72040.30000.017*
C50.6415 (7)0.7705 (5)0.3779 (4)0.0166 (10)
H50.69220.76970.43680.020*
C61.1246 (7)0.3148 (4)0.3390 (4)0.0169 (10)
C70.9392 (7)0.3537 (5)0.3529 (4)0.0187 (10)
H70.85850.30380.41200.022*
C80.8757 (7)0.4642 (4)0.2803 (4)0.0149 (9)
H80.74930.48840.29040.018*
C91.1622 (7)0.5051 (5)0.1839 (4)0.0170 (10)
H91.24070.55900.12640.020*
C101.2371 (7)0.3934 (5)0.2526 (4)0.0191 (10)
H101.36380.37060.24080.023*
C110.3637 (7)0.8866 (4)0.6664 (4)0.0159 (9)
C120.1806 (7)0.9321 (5)0.6507 (4)0.0192 (10)
H120.13570.93260.59010.023*
C130.0699 (7)0.9751 (5)0.7227 (4)0.0206 (10)
H13−0.05231.00450.71200.025*
C140.3048 (8)0.9366 (5)0.8259 (4)0.0202 (10)
H140.34580.94120.88570.024*
C150.4216 (6)0.8902 (4)0.7590 (4)0.0149 (9)
H150.54190.86010.77360.018*
C201.0245 (7)0.6793 (4)−0.0466 (4)0.0175 (10)
C210.7553 (6)0.8525 (4)−0.0305 (4)0.0148 (9)
C220.6898 (7)0.6144 (5)0.0594 (4)0.0197 (10)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Re10.01149 (13)0.01337 (13)0.01111 (13)0.00016 (7)−0.00161 (7)−0.00747 (8)
Cl10.0141 (5)0.0153 (5)0.0144 (5)−0.0007 (4)−0.0023 (4)−0.0091 (4)
O10.0169 (18)0.032 (2)0.0186 (18)0.0003 (15)0.0016 (15)−0.0177 (16)
O20.024 (2)0.0183 (18)0.0187 (18)0.0032 (15)−0.0025 (15)−0.0015 (15)
O30.0179 (18)0.0264 (19)0.0191 (18)0.0058 (15)−0.0019 (14)−0.0144 (15)
O200.026 (2)0.0278 (19)0.0184 (18)−0.0017 (16)0.0063 (16)−0.0159 (16)
O210.025 (2)0.0226 (19)0.0214 (19)0.0016 (16)−0.0089 (16)−0.0037 (16)
O220.024 (2)0.037 (2)0.040 (2)−0.0070 (17)−0.0022 (18)−0.026 (2)
N10.0115 (19)0.0162 (19)0.0112 (18)0.0018 (15)0.0003 (15)−0.0072 (15)
N20.0117 (19)0.0133 (18)0.016 (2)−0.0008 (15)0.0001 (16)−0.0066 (16)
N30.024 (2)0.020 (2)0.023 (2)−0.0028 (18)0.0078 (19)−0.0120 (18)
C10.014 (2)0.017 (2)0.015 (2)−0.0020 (18)0.0015 (18)−0.0073 (18)
C20.016 (2)0.020 (2)0.017 (2)0.0035 (18)−0.0061 (19)−0.0097 (19)
C30.015 (2)0.017 (2)0.016 (2)−0.0007 (18)−0.0037 (18)−0.0090 (19)
C40.017 (2)0.016 (2)0.012 (2)0.0009 (18)−0.0043 (18)−0.0074 (18)
C50.018 (2)0.019 (2)0.016 (2)−0.0022 (19)−0.0033 (19)−0.0102 (19)
C60.020 (2)0.014 (2)0.017 (2)0.0006 (18)−0.0036 (19)−0.0059 (19)
C70.019 (2)0.016 (2)0.017 (2)0.0008 (19)0.002 (2)−0.0053 (19)
C80.013 (2)0.018 (2)0.015 (2)−0.0006 (18)0.0007 (18)−0.0089 (19)
C90.015 (2)0.020 (2)0.016 (2)−0.0006 (18)−0.0006 (19)−0.0077 (19)
C100.015 (2)0.021 (2)0.020 (2)0.0025 (19)−0.002 (2)−0.008 (2)
C110.021 (2)0.014 (2)0.013 (2)0.0001 (18)−0.0003 (19)−0.0074 (18)
C120.022 (3)0.019 (2)0.017 (2)0.005 (2)−0.005 (2)−0.009 (2)
C130.018 (2)0.018 (2)0.027 (3)0.0001 (19)−0.001 (2)−0.012 (2)
C140.027 (3)0.021 (2)0.017 (2)−0.007 (2)0.000 (2)−0.011 (2)
C150.011 (2)0.016 (2)0.022 (2)−0.0007 (17)−0.0068 (19)−0.0106 (19)
C200.021 (3)0.011 (2)0.024 (3)0.0000 (18)−0.008 (2)−0.0085 (19)
C210.010 (2)0.019 (2)0.017 (2)−0.0061 (18)0.0021 (18)−0.0086 (19)
C220.014 (2)0.027 (3)0.016 (2)0.005 (2)0.0001 (19)−0.011 (2)

Geometric parameters (Å, º)

Re1—C221.898 (6)C2—C31.376 (7)
Re1—C211.914 (5)C2—H2A0.9500
Re1—C201.933 (5)C3—H30.9500
Re1—N12.208 (4)C4—C51.383 (7)
Re1—N22.210 (4)C4—H40.9500
Re1—Cl12.4987 (11)C5—H50.9500
O1—C11.333 (6)C6—C101.393 (7)
O1—H10.94 (8)C6—C71.401 (7)
O2—C61.341 (6)C7—C81.367 (7)
O2—H21.01 (7)C7—H70.9500
O3—C111.289 (6)C8—H80.9500
O20—C201.143 (7)C9—C101.387 (7)
O21—C211.151 (6)C9—H90.9500
O22—C221.155 (7)C10—H100.9500
N1—C41.348 (6)C11—C121.426 (7)
N1—C31.362 (6)C11—C151.433 (7)
N2—C81.346 (6)C12—C131.363 (7)
N2—C91.360 (6)C12—H120.9500
N3—C131.353 (7)C13—H130.9500
N3—C141.353 (7)C14—C151.355 (7)
N3—H3A0.97 (7)C14—H140.9500
C1—C21.401 (7)C15—H150.9500
C1—C51.402 (7)
C22—Re1—C2187.9 (2)C5—C4—H4118.2
C22—Re1—C2089.6 (2)C4—C5—C1119.2 (4)
C21—Re1—C2088.6 (2)C4—C5—H5120.4
C22—Re1—N191.96 (19)C1—C5—H5120.4
C21—Re1—N192.49 (18)O2—C6—C10124.3 (5)
C20—Re1—N1178.11 (17)O2—C6—C7117.8 (5)
C22—Re1—N291.80 (19)C10—C6—C7117.8 (4)
C21—Re1—N2177.97 (17)C8—C7—C6119.2 (5)
C20—Re1—N293.45 (18)C8—C7—H7120.4
N1—Re1—N285.51 (15)C6—C7—H7120.4
C22—Re1—Cl1177.81 (16)N2—C8—C7124.0 (5)
C21—Re1—Cl194.05 (14)N2—C8—H8118.0
C20—Re1—Cl191.33 (15)C7—C8—H8118.0
N1—Re1—Cl187.03 (11)N2—C9—C10122.8 (5)
N2—Re1—Cl186.19 (11)N2—C9—H9118.6
C1—O1—H1113 (4)C10—C9—H9118.6
C6—O2—H2109 (4)C9—C10—C6119.2 (5)
C4—N1—C3116.7 (4)C9—C10—H10120.4
C4—N1—Re1124.0 (3)C6—C10—H10120.4
C3—N1—Re1119.2 (3)O3—C11—C12122.0 (5)
C8—N2—C9116.8 (4)O3—C11—C15121.4 (5)
C8—N2—Re1121.6 (3)C12—C11—C15116.6 (4)
C9—N2—Re1121.4 (3)C13—C12—C11120.0 (5)
C13—N3—C14120.9 (5)C13—C12—H12120.0
C13—N3—H3A123 (4)C11—C12—H12120.0
C14—N3—H3A116 (4)N3—C13—C12121.1 (5)
O1—C1—C2118.1 (4)N3—C13—H13119.4
O1—C1—C5124.5 (5)C12—C13—H13119.4
C2—C1—C5117.4 (4)N3—C14—C15121.3 (5)
C3—C2—C1119.6 (5)N3—C14—H14119.4
C3—C2—H2A120.2C15—C14—H14119.4
C1—C2—H2A120.2C14—C15—C11120.0 (5)
N1—C3—C2123.2 (4)C14—C15—H15120.0
N1—C3—H3118.4C11—C15—H15120.0
C2—C3—H3118.4O20—C20—Re1179.5 (4)
N1—C4—C5123.7 (5)O21—C21—Re1177.0 (4)
N1—C4—H4118.2O22—C22—Re1178.1 (4)

Hydrogen-bond geometry (Å, º)

D—H···AD—HH···AD···AD—H···A
O1—H1···O30.94 (8)1.62 (8)2.556 (5)175 (7)
O2—H2···O3i1.01 (7)1.57 (7)2.569 (5)169 (6)
N3—H3A···Cl1ii0.97 (7)2.32 (7)3.218 (5)152 (5)
C9—H9···O22iii0.952.563.317 (7)137
C3—H3···Cl1iv0.952.893.580 (5)131
C14—H14···O21v0.952.623.264 (7)126

Symmetry codes: (i) −x+2, −y+1, −z+1; (ii) −x+1, −y+2, −z+1; (iii) x+1, y, z; (iv) x−1, y, z; (v) x, y, z+1.

Funding Statement

This work was funded by Ministry of Economy, Industry and Competitiveness (Spain) grant . European Regional Development Fund grants CTQ2015-71211-REDT and CTQ2015-7091-R.

This paper was supported by the following grant(s):

Ministry of Economy, Industry and Competitiveness (Spain) .
European Regional Development Fund CTQ2015-71211-REDTCTQ2015-7091-R.

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