supplementary materials


hb6985 scheme

Acta Cryst. (2012). E68, o3462-o3463    [ doi:10.1107/S1600536812047332 ]

5,10,15,20-Tetrakis(4-acetyloxyphenyl)porphyrin including an unknown solvate

M. D. Miranda, M. Ramos Silva, T. M. R. Maria, A. Balakrishna and A. J. F. N. Sobral

Abstract top

Molecules of the title compound, C52H38N4O8, are located on an inversion center so that the asymmetric cell contains one half of the molecule. The macrocycle exhibits a ruffled conformation with a maximum deviation of 0.16 Å for the 24 macrocycle atoms: the dihedral angle between adjacent five-membered rings is 5.13 (19)°. The benzene rings are rotated by 70.25 (19)° with respect to their adjacent protonated five-membered rings, and by 65.56 (19)° with respect to the unprotonated rings. The porphyrin conformation is supported by bifurcated N-H...(N,N) hydrogen bonds. The structure contained poorly resolved solvent molecules in voids of volume 217 Å3 per unit cell. The latter were treated using the SQUEEZE routine in PLATON [Spek (2009). Acta Cryst. D65, 148-155]. As the solvent could not be identified exactly, it was not included in the calculation of the overall formula weight, density and absorption coefficient.

Comment top

This work is part of a project of synthesizing porphyrins and porphyrin percursors (Paixão, Matos Beja et al., 2002; Paixão, Ramos Silva et al., 2002; Paixão et al., 2003; Ramos Silva et al., 2002a,b; Sobral et al., 2001a,b). Our aim is to use the tremendous potential for the manifold applications of porphyrins and obtain molecular magnets (Zhang et al., 2010), liquid crystals (Eichhorn, 2000), multi-porous materials for CO2 sequestering and possibly some properties combined. In the title compound, Fig. 1, 5,10,15,20-Tetrakis[(4-methylcarbonyl)oxy]-phenylporphyrin, the porphyrin moiety shows a non planar ruffled conformation. The phenyl rings are rotated with respect to the porphyrin ring. The angle between the least-squares plane containing the porphyrin core and the least-squares plane of the phenyl ring C11—C16 is 65.29 (14)° [74.18 (13)° for C19—C24]. Intramolecular N—H···N hydrogen bonds are present. The molecules pile in columns along the a axis. There are solvent acessible voids in the crystal structure that accomodate solvent molecules in a very disordered way; these solvent molecules were not included in the calculation of the overall formula weight, density and absorption coefficient.

Related literature top

For general background on porphyrin and porphyrin precursors synthesized in our group, see Paixão, Matos Beja et al. (2002); Paixão, Ramos Silva et al. (2002); Paixão et al. (2003); Ramos Silva et al. (2002a,b); Sobral et al. (2001a,b). For the applications of porphyrins, see: Zhang et al. (2010); Eichhorn (2000).

Experimental top

All reagents were used as purchased, except pyrrole that was distillated under reduced pressure. The tetrakys-(pheny-4-acetate)-21H,22H-porphine was synthesized by the method of Rothemund/Adler/Long [1–2]. The aldehyde 4-formylphenyl acetate (1 g, 6.1 mmol) was added to propionic acid (150 ml). The solution was placed to reflux and then pyrrole (0.5 ml, 7.207 mmol) was added drop wise during 10 minutes. The solution was left at 120 C for 4 h. The solvent was then evaporated and the crude, dissolved in dichloromethane, was washed with aqueous NaHCO3 and distilled water and dried with Na2SO4 anhydrous. The final porphyrin tetrakys-(pheny-4-acetate)-21H,22H-porphine was obtained after purification by column chromatography in silica/dichloromethane. Recrystallization in dichloromethane/hexane gives the purple crystals of tetrakys-(pheny-4-acetate)-21H,22H-porphine (yield of 5% relatively to pyrrole). HPLC/MS showed a single signal corresponding to the expected molecular ion m/z 847.

Refinement top

H atoms bound to C atoms were placed at calculated positions and were treated as riding on the parent atoms with C—H = 0.93 Å (aromatic) and with Uiso(H) = 1.2 Ueq(C). In a final difference Fourier map highly disordered electron density occupying one cavity of ca 215 Å3 each was observed. This residual electron density was difficult to model and therefore, the SQUEEZE routine in PLATON (Spek, 2009) was used to eliminate this contribution of the electron density in the solvent region from the intensity data. The solvent-free model was employed for the final refinement. One of the methylcarbonyloxy terminal groups shows signs of disorder, possibly occupying two or more sites but such disorder could not be resolved in the present experiment. The solvent molecules were not included in the calculation of the overall formula weight, density and absorption coefficient.

Computing details top

Data collection: SMART (Bruker, 2003); cell refinement: SAINT (Bruker, 2003); data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. ORTEPII (Johnson, 1976) plot of the title compound. Displacement ellipsoids are drawn at the 50% level.
[Figure 2] Fig. 2. Packing of the molecules in the unit cell showing the H-bonds as dashed lines.
5,10,15,20-Tetrakis(4-acetyloxyphenyl)porphyrin including an unknown solvate top
Crystal data top
C52H38N4O8Z = 1
Mr = 846.86F(000) = 442
Triclinic, P1Dx = 1.174 Mg m3
a = 6.6203 (2) ÅMo Kα radiation, λ = 0.71073 Å
b = 14.1043 (3) ÅCell parameters from 4592 reflections
c = 14.4936 (3) Åθ = 2.9–21.4°
α = 113.862 (1)°µ = 0.08 mm1
β = 97.771 (2)°T = 293 K
γ = 98.060 (2)°Plate, violet
V = 1197.58 (5) Å30.30 × 0.12 × 0.04 mm
Data collection top
Bruker APEX CCD area-detector
diffractometer
4566 independent reflections
Radiation source: fine-focus sealed tube2956 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.031
φ and ω scansθmax = 25.8°, θmin = 1.6°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2000)
h = 88
Tmin = 0.790, Tmax = 0.999k = 1717
24062 measured reflectionsl = 1717
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)] = 0.080Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.248H-atom parameters constrained
S = 1.14 w = 1/[σ2(Fo2) + (0.1221P)2 + 0.5589P]
where P = (Fo2 + 2Fc2)/3
4566 reflections(Δ/σ)max = 0.040
291 parametersΔρmax = 0.98 e Å3
0 restraintsΔρmin = 0.51 e Å3
Crystal data top
C52H38N4O8γ = 98.060 (2)°
Mr = 846.86V = 1197.58 (5) Å3
Triclinic, P1Z = 1
a = 6.6203 (2) ÅMo Kα radiation
b = 14.1043 (3) ŵ = 0.08 mm1
c = 14.4936 (3) ÅT = 293 K
α = 113.862 (1)°0.30 × 0.12 × 0.04 mm
β = 97.771 (2)°
Data collection top
Bruker APEX CCD area-detector
diffractometer
4566 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2000)
2956 reflections with I > 2σ(I)
Tmin = 0.790, Tmax = 0.999Rint = 0.031
24062 measured reflectionsθmax = 25.8°
Refinement top
R[F2 > 2σ(F2)] = 0.080H-atom parameters constrained
wR(F2) = 0.248Δρmax = 0.98 e Å3
S = 1.14Δρmin = 0.51 e Å3
4566 reflectionsAbsolute structure: ?
291 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'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 > σ(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
N10.7700 (3)0.90482 (18)0.36681 (17)0.0397 (6)
H10.85530.95290.42120.048*
N21.1829 (3)1.03171 (17)0.41002 (17)0.0400 (6)
O10.8965 (4)0.7835 (2)0.19208 (16)0.0709 (7)
O21.2299 (4)0.8442 (2)0.1891 (2)0.0810 (8)
O30.1992 (4)0.5305 (2)0.3829 (3)0.0907 (9)
O40.1461 (12)0.4164 (5)0.2427 (5)0.270 (4)
C10.5249 (4)0.8381 (2)0.4526 (2)0.0404 (7)
C20.5916 (4)0.8419 (2)0.3666 (2)0.0399 (7)
C30.4952 (4)0.7749 (2)0.2613 (2)0.0477 (8)
H30.37130.72400.23770.057*
C40.6157 (5)0.7981 (3)0.2015 (2)0.0511 (8)
H40.58810.76640.12970.061*
C50.7918 (4)0.8795 (2)0.2676 (2)0.0418 (7)
C60.9617 (4)0.9196 (2)0.2367 (2)0.0414 (7)
C71.1447 (4)0.9906 (2)0.3043 (2)0.0419 (7)
C81.3182 (5)1.0335 (2)0.2720 (2)0.0513 (8)
H81.33061.01760.20440.062*
C91.4573 (5)1.1004 (3)0.3576 (2)0.0511 (8)
H91.58461.14020.36060.061*
C101.3752 (4)1.1001 (2)0.4445 (2)0.0410 (7)
C110.9478 (5)0.8834 (2)0.1239 (2)0.0453 (7)
C121.0830 (5)0.8245 (3)0.0745 (2)0.0601 (9)
H121.18290.80670.11250.072*
C131.0738 (6)0.7915 (3)0.0297 (3)0.0672 (10)
H131.16580.75170.06200.081*
C140.9254 (5)0.8187 (3)0.0849 (2)0.0558 (9)
C150.7864 (5)0.8749 (3)0.0391 (2)0.0579 (9)
H150.68480.89130.07770.070*
C160.7987 (5)0.9072 (3)0.0653 (2)0.0529 (8)
H160.70460.94580.09690.063*
C171.0572 (6)0.7993 (3)0.2359 (3)0.0599 (9)
C180.9824 (6)0.7539 (3)0.3500 (3)0.0720 (11)
H18A0.99960.80980.37180.108*
H18B0.83750.71970.36820.108*
H18C1.06200.70300.38340.108*
C190.3332 (4)0.7556 (2)0.4305 (2)0.0411 (7)
C200.1366 (5)0.7666 (3)0.3969 (3)0.0550 (8)
H200.12150.82760.38880.066*
C210.0373 (5)0.6893 (3)0.3751 (3)0.0620 (9)
H210.16850.69670.35050.074*
C220.0155 (5)0.6014 (3)0.3900 (3)0.0575 (9)
C230.1759 (5)0.5883 (3)0.4238 (3)0.0658 (10)
H230.18960.52800.43340.079*
C240.3492 (5)0.6658 (3)0.4436 (3)0.0575 (9)
H240.48040.65700.46640.069*
C250.2590 (11)0.4459 (5)0.3054 (5)0.119 (2)
C260.4600 (7)0.3784 (4)0.2982 (4)0.1021 (16)
H26A0.46790.30640.25020.153*
H26B0.57420.40390.27480.153*
H26C0.46770.38120.36490.153*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0341 (12)0.0479 (12)0.0322 (12)0.0020 (10)0.0051 (9)0.0165 (10)
N20.0370 (13)0.0456 (12)0.0342 (12)0.0015 (10)0.0070 (10)0.0176 (10)
O10.0544 (14)0.1086 (19)0.0343 (11)0.0056 (13)0.0089 (10)0.0232 (12)
O20.0619 (16)0.0996 (19)0.0612 (15)0.0139 (15)0.0127 (13)0.0248 (14)
O30.0685 (18)0.0697 (16)0.109 (2)0.0121 (14)0.0007 (16)0.0276 (16)
O40.299 (7)0.196 (5)0.175 (5)0.122 (5)0.121 (5)0.023 (4)
C10.0297 (14)0.0450 (14)0.0472 (16)0.0001 (12)0.0055 (12)0.0239 (12)
C20.0334 (14)0.0447 (14)0.0406 (15)0.0011 (12)0.0046 (11)0.0207 (12)
C30.0365 (15)0.0565 (17)0.0412 (16)0.0064 (13)0.0007 (12)0.0199 (14)
C40.0438 (17)0.0618 (18)0.0358 (15)0.0013 (14)0.0014 (13)0.0166 (14)
C50.0394 (15)0.0483 (15)0.0353 (14)0.0039 (13)0.0025 (12)0.0191 (12)
C60.0424 (15)0.0488 (15)0.0327 (14)0.0037 (13)0.0065 (12)0.0196 (12)
C70.0421 (16)0.0486 (15)0.0362 (14)0.0010 (13)0.0090 (12)0.0221 (12)
C80.0513 (18)0.0622 (18)0.0382 (15)0.0011 (15)0.0123 (13)0.0229 (14)
C90.0425 (16)0.0617 (18)0.0452 (16)0.0079 (14)0.0144 (13)0.0236 (14)
C100.0362 (15)0.0457 (14)0.0408 (15)0.0016 (12)0.0069 (12)0.0210 (12)
C110.0430 (16)0.0534 (16)0.0367 (15)0.0012 (13)0.0084 (12)0.0198 (13)
C120.0515 (19)0.085 (2)0.0425 (17)0.0186 (17)0.0065 (14)0.0258 (16)
C130.060 (2)0.089 (3)0.0459 (19)0.0179 (19)0.0127 (16)0.0211 (18)
C140.0491 (18)0.075 (2)0.0317 (15)0.0069 (16)0.0033 (13)0.0195 (15)
C150.0530 (19)0.079 (2)0.0444 (17)0.0081 (17)0.0056 (14)0.0324 (16)
C160.0493 (18)0.0665 (19)0.0443 (17)0.0124 (15)0.0132 (14)0.0243 (15)
C170.060 (2)0.067 (2)0.0448 (18)0.0034 (17)0.0142 (16)0.0192 (16)
C180.079 (3)0.086 (3)0.0442 (19)0.010 (2)0.0208 (18)0.0222 (18)
C190.0344 (15)0.0481 (15)0.0400 (15)0.0001 (12)0.0073 (11)0.0214 (12)
C200.0360 (16)0.0550 (17)0.078 (2)0.0039 (14)0.0074 (15)0.0366 (16)
C210.0350 (17)0.067 (2)0.085 (2)0.0023 (15)0.0050 (16)0.0390 (18)
C220.0392 (17)0.0559 (18)0.068 (2)0.0092 (15)0.0073 (15)0.0252 (16)
C230.053 (2)0.0539 (18)0.092 (3)0.0018 (16)0.0063 (18)0.0406 (18)
C240.0377 (17)0.0606 (19)0.078 (2)0.0025 (14)0.0046 (15)0.0387 (17)
C250.136 (5)0.106 (4)0.081 (3)0.023 (4)0.005 (3)0.027 (3)
C260.071 (3)0.084 (3)0.126 (4)0.032 (2)0.001 (3)0.042 (3)
Geometric parameters (Å, º) top
N1—C51.368 (4)C11—C161.380 (4)
N1—C21.374 (3)C11—C121.380 (5)
N1—H10.8600C12—C131.378 (5)
N2—C71.372 (3)C12—H120.9300
N2—C101.376 (3)C13—C141.376 (5)
O1—C171.348 (4)C13—H130.9300
O1—C141.402 (4)C14—C151.364 (5)
O2—C171.187 (4)C15—C161.379 (4)
O3—C251.226 (6)C15—H150.9300
O3—C221.425 (4)C16—H160.9300
O4—C251.235 (8)C17—C181.490 (5)
C1—C21.395 (4)C18—H18A0.9600
C1—C10i1.394 (4)C18—H18B0.9600
C1—C191.497 (4)C18—H18C0.9600
C2—C31.425 (4)C19—C241.370 (4)
C3—C41.356 (4)C19—C201.379 (4)
C3—H30.9300C20—C211.373 (4)
C4—C51.424 (4)C20—H200.9300
C4—H40.9300C21—C221.365 (5)
C5—C61.396 (4)C21—H210.9300
C6—C71.406 (4)C22—C231.360 (5)
C6—C111.488 (4)C23—C241.378 (4)
C7—C81.445 (4)C23—H230.9300
C8—C91.333 (4)C24—H240.9300
C8—H80.9300C25—C261.489 (7)
C9—C101.439 (4)C26—H26A0.9600
C9—H90.9300C26—H26B0.9600
C10—C1i1.394 (4)C26—H26C0.9600
C5—N1—C2109.8 (2)C15—C14—C13121.4 (3)
C5—N1—H1125.1C15—C14—O1115.9 (3)
C2—N1—H1125.1C13—C14—O1122.5 (3)
C7—N2—C10105.8 (2)C14—C15—C16119.0 (3)
C17—O1—C14121.0 (3)C14—C15—H15120.5
C25—O3—C22118.6 (5)C16—C15—H15120.5
C2—C1—C10i126.2 (3)C11—C16—C15121.4 (3)
C2—C1—C19116.0 (2)C11—C16—H16119.3
C10i—C1—C19117.6 (3)C15—C16—H16119.3
N1—C2—C1126.8 (2)O2—C17—O1124.2 (3)
N1—C2—C3106.9 (2)O2—C17—C18126.3 (3)
C1—C2—C3126.2 (3)O1—C17—C18109.5 (3)
C4—C3—C2108.1 (2)C17—C18—H18A109.5
C4—C3—H3126.0C17—C18—H18B109.5
C2—C3—H3126.0H18A—C18—H18B109.5
C3—C4—C5108.2 (3)C17—C18—H18C109.5
C3—C4—H4125.9H18A—C18—H18C109.5
C5—C4—H4125.9H18B—C18—H18C109.5
N1—C5—C6126.7 (2)C24—C19—C20117.8 (3)
N1—C5—C4107.0 (3)C24—C19—C1120.2 (3)
C6—C5—C4126.2 (3)C20—C19—C1121.9 (3)
C5—C6—C7124.7 (3)C21—C20—C19121.2 (3)
C5—C6—C11117.3 (2)C21—C20—H20119.4
C7—C6—C11118.0 (3)C19—C20—H20119.4
N2—C7—C6125.5 (3)C22—C21—C20119.3 (3)
N2—C7—C8110.0 (2)C22—C21—H21120.4
C6—C7—C8124.5 (3)C20—C21—H21120.4
C9—C8—C7106.8 (3)C21—C22—C23121.0 (3)
C9—C8—H8126.6C21—C22—O3118.3 (3)
C7—C8—H8126.6C23—C22—O3120.1 (3)
C8—C9—C10107.8 (3)C22—C23—C24119.0 (3)
C8—C9—H9126.1C22—C23—H23120.5
C10—C9—H9126.1C24—C23—H23120.5
N2—C10—C1i125.9 (3)C23—C24—C19121.6 (3)
N2—C10—C9109.6 (2)C23—C24—H24119.2
C1i—C10—C9124.6 (3)C19—C24—H24119.2
C16—C11—C12117.9 (3)O3—C25—O4120.1 (6)
C16—C11—C6121.1 (3)O3—C25—C26116.5 (6)
C12—C11—C6121.0 (3)O4—C25—C26123.1 (5)
C13—C12—C11121.7 (3)C25—C26—H26A109.5
C13—C12—H12119.1C25—C26—H26B109.5
C11—C12—H12119.1H26A—C26—H26B109.5
C14—C13—C12118.5 (3)C25—C26—H26C109.5
C14—C13—H13120.7H26A—C26—H26C109.5
C12—C13—H13120.7H26B—C26—H26C109.5
C5—N1—C2—C1174.5 (3)C7—C6—C11—C1263.6 (4)
C5—N1—C2—C31.0 (3)C16—C11—C12—C131.1 (5)
C10i—C1—C2—N11.9 (5)C6—C11—C12—C13179.2 (3)
C19—C1—C2—N1175.0 (3)C11—C12—C13—C140.1 (6)
C10i—C1—C2—C3176.6 (3)C12—C13—C14—C151.5 (5)
C19—C1—C2—C30.3 (4)C12—C13—C14—O1176.2 (3)
N1—C2—C3—C40.2 (3)C17—O1—C14—C15131.0 (4)
C1—C2—C3—C4175.3 (3)C17—O1—C14—C1354.0 (5)
C2—C3—C4—C50.6 (4)C13—C14—C15—C161.5 (5)
C2—N1—C5—C6174.2 (3)O1—C14—C15—C16176.6 (3)
C2—N1—C5—C41.4 (3)C12—C11—C16—C151.1 (5)
C3—C4—C5—N11.2 (4)C6—C11—C16—C15179.3 (3)
C3—C4—C5—C6174.4 (3)C14—C15—C16—C110.2 (5)
N1—C5—C6—C72.8 (5)C14—O1—C17—O21.2 (6)
C4—C5—C6—C7171.9 (3)C14—O1—C17—C18179.9 (3)
N1—C5—C6—C11177.8 (3)C2—C1—C19—C24105.4 (3)
C4—C5—C6—C117.5 (5)C10i—C1—C19—C2471.8 (4)
C10—N2—C7—C6177.7 (3)C2—C1—C19—C2074.7 (4)
C10—N2—C7—C80.6 (3)C10i—C1—C19—C20108.2 (3)
C5—C6—C7—N20.6 (5)C24—C19—C20—C211.3 (5)
C11—C6—C7—N2179.9 (3)C1—C19—C20—C21178.7 (3)
C5—C6—C7—C8178.7 (3)C19—C20—C21—C221.9 (6)
C11—C6—C7—C81.9 (5)C20—C21—C22—C231.4 (6)
N2—C7—C8—C90.7 (4)C20—C21—C22—O3170.2 (3)
C6—C7—C8—C9177.6 (3)C25—O3—C22—C21104.7 (5)
C7—C8—C9—C100.5 (4)C25—O3—C22—C2383.6 (6)
C7—N2—C10—C1i178.3 (3)C21—C22—C23—C240.3 (6)
C7—N2—C10—C90.3 (3)O3—C22—C23—C24171.1 (3)
C8—C9—C10—N20.1 (4)C22—C23—C24—C190.3 (6)
C8—C9—C10—C1i178.7 (3)C20—C19—C24—C230.2 (5)
C5—C6—C11—C1663.8 (4)C1—C19—C24—C23179.9 (3)
C7—C6—C11—C16116.7 (3)C22—O3—C25—O410.6 (10)
C5—C6—C11—C12115.8 (3)C22—O3—C25—C26175.6 (4)
Symmetry code: (i) x+2, y+2, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···N20.862.352.885 (3)121
N1—H1···N2i0.862.422.944 (3)120
Symmetry code: (i) x+2, y+2, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···N20.86002.35002.885 (3)121.00
N1—H1···N2i0.86002.42002.944 (3)120.00
Symmetry code: (i) x+2, y+2, z+1.
Acknowledgements top

This work was supported by Fundo Europeu de Desenvolvimento Regional-QREN-COMPETE through project PEst-C/FIS/UI0036/2011, PTDC/AAC-CLI/098308/2008 and PTDC/AAC-CLI/118092/2010 – Fundação para a Ciência e a Tecnologia (FCT).

references
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