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ISSN: 2056-9890
Volume 71| Part 10| October 2015| Pages 1245-1249

Crystal structure of 4′-{[4-(2,2′:6′,2′′-terpyrid­yl-4′-yl)phen­yl]ethyn­yl}bi­phenyl-4-yl (2,2,5,5-tetra­methyl-1-oxyl-3-pyrrolin-3-yl)formate benzene 2.5-solvate

CROSSMARK_Color_square_no_text.svg

aUniversity of Bonn, Institute of Physical and Theoretical Chemistry, Wegelerstr. 12, 53115 Bonn, Germany, and bUniversity of Bonn, Institute of Inorganic Chemistry, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany
*Correspondence e-mail: schiemann@pc.uni-bonn.de

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 7 September 2015; accepted 21 September 2015; online 26 September 2015)

The title compound, C44H35N4O3·2.5C6H6 (1), consists of a terpyridine and a N-oxylpyrroline-3-formate group separated by an aromatic spacer, viz. 4-(phenyl­ethyn­yl)-1,1′-biphenyl. It crystallized in the triclinic space group P-1 with two and a half benzene solvate mol­ecules (one benzene mol­ecule is located about an inversion center), while the di­chloro­methane solvate (2) of the same mol­ecule [Ackermann et al. (2015[Ackermann, K., Giannoulis, A., Cordes, D. B., Slawin, A. M. Z. & Bode, B. E. (2015). Chem. Commun. 51, 5257-5260.]). Chem. Commun. 51, 5257–5260] crystallized in the tetra­gonal space group P42/n, with considerable disorder in the mol­ecule. In (1), the terpyridine (terpy) group assumes an all-trans conformation typical for terpyridines. It is essentially planar with the two outer pyridine rings (B and C) inclined to the central pyridine ring (A) by 8.70 (15) and 14.55 (14)°, respectively. The planes of the aromatic spacer (D, E and F) are nearly coplanar with dihedral angles D/E, D/F and E/F being 3.42 (15), 5.80 (15) and 4.00 (16)°, respectively. It is twisted with respect to the terpy group with, for example, dihedral angle A/D being 24.48 (14)°. The mean plane of the N-oxylpyrroline is almost normal to the biphenyl ring F, making a dihedral angle of 86.57 (16)°, and it is inclined to pyridine ring A by 72.61 (15)°. The intra­molecular separation between the O atom of the nitroxyl group and the N atom of the central pyridine ring of the terpyridine group is 25.044 (3) Å. In the crystal, mol­ecules are linked by pairs of C—H⋯O hydrogen bonds, forming inversion dimers. The dimers stack along the c axis forming columns. Within and between the columns, the spaces are occupied by benzene mol­ecules. The shortest oxygen–oxygen separation between nitroxyl groups is 4.004 (4) Å. The details of the title compound are compared with those of the di­chloro­methane solvate (2) and with the structure of a related mol­ecule, 4′-{4-[(2,2,5,5-tetra­methyl-N-oxyl-3-pyrrolin-3-yl)ethyn­yl]phen­yl}-2,2′:6′,2′′-terpyridine (3), which has an ethynylphenyl spacer [Meyer et al. (2015). Acta Cryst. E71, 870–874].

1. Chemical context

The title compound (1) was synthesized as a ligand for 3d metal ions in the framework of a pulsed EPR study on metal–nitroxyl model systems. It contains a nitroxyl group and a terpyridine (terpy) group which is capable of taking up metal ions. The title compound resembles compound (3) (4′-{4-[(2,2,5,5-tetra­methyl-N-oxyl-3-pyrrolin-3-yl)ethyn­yl]phen­yl}-2,2′:6′,2′′-terpyridine), which has an ethynylphenyl spacer (Meyer et al., 2015a[Meyer, A., Wiecek, J., Schnakenburg, G. & Schiemann, O. (2015a). Acta Cryst. E71, 870-874.]), compared to the phenyl­ethynylbiphenyl spacer in the title compound (1). Nitroxyls are of inter­est in various branches of chemistry including magnetochemistry (Rajca et al., 2006[Rajca, A., Mukherjee, S., Pink, M. & Rajca, S. (2006). J. Am. Chem. Soc. 128, 13497-13507.]; Fritscher et al., 2002[Fritscher, J., Beyer, M. & Schiemann, O. (2002). Chem. Phys. Lett. 364, 393-401.]), synthetic chemistry (Hoover & Stahl, 2011[Hoover, J. M. & Stahl, S. S. (2011). J. Am. Chem. Soc. 133, 16901-16910.]; Fey et al., 2001[Fey, T., Fischer, H., Bachmann, S., Albert, K. & Bolm, C. (2001). J. Org. Chem. 66, 8154-8159.]) and structural biology (Reginsson & Schiemann, 2011[Reginsson, G. W. & Schiemann, O. (2011). Biochem. Soc. Trans. 39, 128-139.]). Terpyridines show pH-dependent luminescence properties which have been analyzed in terms of a pH-dependent cistrans isomerization (Nakamoto, 1960[Nakamoto, K. (1960). J. Phys. Chem. 64, 1420-1425.]; Fink & Ohnesorge, 1970[Fink, D. W. & Ohnesorge, W. E. (1970). J. Phys. Chem. 74, 72-77.]). Structural investigations in the solid state reveal an exclusive preference for the trans conformation (Fallahpour et al., 1999[Fallahpour, R.-A., Neuburger, M. & Zehnder, M. (1999). Polyhedron, 18, 2445-2454.]; Eryazici et al., 2006[Eryazici, I., Moorefield, C. N., Durmus, S. & Newkome, G. R. (2006). J. Org. Chem. 71, 1009-1014.]; Bessel et al., 1992[Bessel, C. A., See, R. F., Jameson, D. L., Churchill, M. R. & Takeuchi, K. J. (1992). J. Chem. Soc. Dalton Trans. pp. 3223-3228.]; Grave et al., 2003[Grave, C., Lentz, D., Schäfer, A., Samorì, P., Rabe, P. J., Franke, P. & Schlüter, A. D. (2003). J. Am. Chem. Soc. 125, 6907-6918.]). Terpyridines have been shown to be versatile ligands for various metal ions (Hogg & Wilkins, 1962[Hogg, R. & Wilkins, R. G. (1962). J. Chem. Soc. pp. 341-350.]; Constable et al., 1999[Constable, E. C., Baum, G., Bill, E., Dyson, R., van Eldik, R., Fenske, D., Kaderli, D., Morris, D., Neubrand, A., Neuburger, M., Smith, D. R., Wieghardt, K., Zehnder, M. & Zuberbühler, A. D. (1999). Chem. Eur. J. 5, 498-508.]; Narr et al., 2002[Narr, E., Godt, A. & Jeschke, G. (2002). Angew. Chem. Int. Ed. 41, 3907-3910.]; Meyer et al., 2015b[Meyer, A., Schnakenburg, G., Glaum, R. & Schiemann, O. (2015b). Inorg. Chem. 54, 8456-8464.]; Folgado et al., 1990[Folgado, J. V., Henke, W., Allmann, R., Stratemeier, H., Beltrán-Porter, D., Rojo, T. & Reinen, D. (1990). Inorg. Chem. 29, 2035-2042.]).

[Scheme 1]

2. Structural commentary

The mol­ecular structure of the title compound, (1), is shown in Fig. 1[link]. The crystal structure of the di­chloro­methane solvate (2) of the title compound has been reported (Ackermann et al., 2015[Ackermann, K., Giannoulis, A., Cordes, D. B., Slawin, A. M. Z. & Bode, B. E. (2015). Chem. Commun. 51, 5257-5260.]). However, these authors used a different protocol for the crystallization of (1) and the conformation of (2) differs markedly from the one presented herein, as shown in the structural overlay of the two compounds (Fig. 2[link]). The structural overlay of compounds (1) and (3) also illustrate the differences in their conformations (Fig. 3[link]).

[Figure 1]
Figure 1
The mol­ecular structure of the title compound (1), with atom labelling. Displacement ellipsoids are drawn at 50% probability level. The benzene mol­ecules and the H atoms have been omitted for clarity.
[Figure 2]
Figure 2
The structural overlay of compounds (1) and (2) [title compound (1) blue, compound (2 – the di­chloro­methane solvate (Ackermann et al., 2015[Ackermann, K., Giannoulis, A., Cordes, D. B., Slawin, A. M. Z. & Bode, B. E. (2015). Chem. Commun. 51, 5257-5260.]) – red].
[Figure 3]
Figure 3
The structural overlay of compounds (1) and (3) [title compound (1) blue, compound (3) – (Meyer et al., 2015a[Meyer, A., Wiecek, J., Schnakenburg, G. & Schiemann, O. (2015a). Acta Cryst. E71, 870-874.]) – green].

In (1) the terpy group assumes the usual all–trans conformation (Meyer et al., 2015a[Meyer, A., Wiecek, J., Schnakenburg, G. & Schiemann, O. (2015a). Acta Cryst. E71, 870-874.]; Fallahpour et al., 1999[Fallahpour, R.-A., Neuburger, M. & Zehnder, M. (1999). Polyhedron, 18, 2445-2454.]; Eryazici et al., 2006[Eryazici, I., Moorefield, C. N., Durmus, S. & Newkome, G. R. (2006). J. Org. Chem. 71, 1009-1014.]; Bessel et al., 1992[Bessel, C. A., See, R. F., Jameson, D. L., Churchill, M. R. & Takeuchi, K. J. (1992). J. Chem. Soc. Dalton Trans. pp. 3223-3228.]; Grave et al., 2003[Grave, C., Lentz, D., Schäfer, A., Samorì, P., Rabe, P. J., Franke, P. & Schlüter, A. D. (2003). J. Am. Chem. Soc. 125, 6907-6918.]). It is essentially planar with the two outer rings B (N3/C35–C39) and C (N4/C40–C44) being inclined to the central pyridine ring A (N2/C30–C34) by 8.70 (15) and 14.55 (14)°, respectively. The conformation of the nitroxyl group in (1) is similar to that found in (3), with a planar pyrroline (N1/C1–C4) ring assuming an angle of 72.61 (15)° to the central pyridine ring A [see also Margraf et al. (2009[Margraf, D., Schuetz, D., Prisner, T. F. & Bats, J. W. (2009). Acta Cryst. E65, o1784.]) and Schuetz et al. (2010[Schuetz, D., Margraf, D., Prisner, T. F. & Bats, J. W. (2010). Acta Cryst. E66, o729-o730.])]. In (3) this dihedral angle is 88.44 (7)°, while in (2) the same dihedral angle is 21.6 (2)°.

The N-oxylpyrroline-3-formate subunit is linked by a rigid spacer, consisting of a 4,4′-bi­phenyl­ene, an ethynylene and a p-phenyl­ene group, to the terpy subunit. The intra­molecular separation of the nitroxyl and the terpy group is 25.044 (3) Å (measured between O1 and N2). The three phenyl groups within the spacer are nearly coplanar, with dihedral angles between the rings of 4.00 (16)°, for rings D (C10–C15) and E (C16–C21), and 3.42 (15)° for rings E and F (C24–C29). Compared to the structure of (3), the spacer is closer to coplanarity to the central pyridine ring: dihedral angle A/D is 24.48 (14)°, compared to 51.36 (7)° in (3). The ethynylene group is slightly bent as in (3), with angle C19–C22–C23 = 174.6 (3) and C22–C23–C24 = 177.8 (3)°. There are short C—H⋯N contacts in the mol­ecule of 2.48 Å (H31⋯N3) and 2.49 Å (H34⋯N4). The same short contacts are also observed in (3). Such contacts have been classified as hydrogen bonds by Murguly et al. (1999[Murguly, E., Norsten, T. B. & Branda, N. (1999). J. Chem. Soc. Perkin Trans. 2, pp. 2789-2794.]).

3. Supra­molecular features

In the crystal of (1), Fig. 4[link], mol­ecules form layers which are nearly coplanar with the (0[\overline{1}]1) plane. Neighbouring layers differ in the orientation of the mol­ecules and each layer is separated by layers of solvent mol­ecules. This arrangement possibly leads to favorable dispersive inter­actions although only one short C—H⋯π contact is observed between the solvent mol­ecules and mol­ecules of (1) (Table 1[link]). Short ππ contacts are observed between the C rings of neighbouring mol­ecules and between the B and C rings (Fig. 5[link]). The centroid-to-centroid distances are 3.678 (2) and 3.8915 (18) Å, respectively, and can be classified as slipped face-to-face π-inter­actions (Janiak, 2000[Janiak, C. (2000). J. Chem. Soc. Dalton Trans. pp. 3885-3896.]).

Table 1
Hydrogen-bond geometry (Å, °)

Cg4, Cg7 and Cg10 are the centroids of pyridine ring N4/C40–C44, spacer ring C24–C29 and benzene ring C54–C59, respectively.

D—H⋯A D—H H⋯A DA D—H⋯A
C37—H37⋯O1i 0.95 2.65 3.228 (4) 120
C38—H38⋯O2ii 0.95 2.55 3.485 (4) 169
C6—H6C⋯O1iii 0.98 2.61 3.499 (4) 151
C9—H9BCg4iv 0.96 2.79 3.602 (4) 140
C14—H14⋯Cg10v 0.95 2.88 3.608 (4) 134
C14—H14⋯Cg10vi 0.95 2.88 3.608 (4) 134
C55—H55⋯Cg7vii 0.95 2.90 3.680 (3) 140
Symmetry codes: (i) x+3, y+1, z+1; (ii) -x+4, -y+1, -z+1; (iii) -x, -y, -z; (iv) x-2, y-1, z-1; (v) x-1, y, z; (vi) -x+2, -y, -z+1; (vii) -x+3, -y+1, -z+1.
[Figure 4]
Figure 4
Crystal packing of the title compound viewed along the a axis. Weak C—H⋯O hydrogen bonds are shown as dashed lines (see Table 1[link]). H atoms not involved in C—H⋯O bonds have been omitted for clarity.
[Figure 5]
Figure 5
π-stacking inter­actions between pyridine rings of neighboring mol­ecules. H atoms have been omitted for clarity.

Within the planes, there are weak C—H⋯O hydrogen bonds between the nitroxyl-O atom and the para-hydrogen atom of pyridine ring B (Table 1[link]). Furthermore, two weak hydrogen bonds per mol­ecule are formed between pairs of layers (Table 1[link]). One of these hydrogen bonds involves the nitroxyl O atom and a hydrogen atom of a methyl group of a mol­ecule from a neighboring layer. The other hydrogen bond is formed between the carbonylic O atom of the carboxyl­ate group and a meta-hydrogen atom of one of the outer pyridine rings of a mol­ecule from a neighboring layer. As the layers are hydrogen bonded pair-wise, the structure can also be described as consisting of double-layers.

It is noteworthy that the arrangement of the mol­ecules of the title compound strongly depends upon the solvents of crystallization. In compound (1), the mol­ecules are arranged in layers and the benzene mol­ecules fill out the channels between the layers formed by the aromatic spacers of the mol­ecule. Close inter­molecule contacts exist only between the functional groups. In the structure of (2) (Ackermann et al., 2015[Ackermann, K., Giannoulis, A., Cordes, D. B., Slawin, A. M. Z. & Bode, B. E. (2015). Chem. Commun. 51, 5257-5260.]), the solvent of crystallization is di­chloro­methane instead of benzene and mol­ecules are arranged having fourfold rotational site symmetry. The solvent mol­ecules fill out channels between the mol­ecules of (2), as in (1). However, the CH2Cl2 solvent mol­ecules in (2) are in close proximity to the terpyridine groups instead of to the aromatic spacer. Weak hydrogen bonds are formed predominantly involving the O atoms as acceptors and the pyrroline and the pyridine rings as donors, as observed in (2) and (3). The shortest oxygen–oxygen separation between neighboring nitroxyl groups is 4.004 (4) Å. This O⋯O distance is an important factor determining the strength of through space exchange inter­actions of nitroxyls (Rajca et al. 2006[Rajca, A., Mukherjee, S., Pink, M. & Rajca, S. (2006). J. Am. Chem. Soc. 128, 13497-13507.]).

4. Database survey

The Cambridge Structural Database (CSD, Version 5.36; Groom & Allen, 2014[Groom, C. R. & Allen, F. H. (2014). Angew. Chem. Int. Ed. 53, 662-671.]) has not been updated since our presentation of the structure of (2). The CSD query revealed, that non-coordinated terpyridines are arranged in an all-trans conformation, unless they are either protonated, li­thia­ted or cannot assume an all-trans conformation for reasons of steric hindrance.

5. Synthesis and crystallization

The synthesis of the title compound (1), is illustrated in Fig. 6[link]. 480 mg (1.45 mmol) of 4′-(4-ethynylphen­yl)-2,2′:6′,2′′-terpyridine (Grosshenny & Ziessel, 1993[Grosshenny, V. & Ziessel, R. (1993). J. Organomet. Chem. 453, C19-C22.]), 780 mg (1.69 mmol) of 4′-iodo-p-biphen-4-yl-N-oxyl-2,2,5,5-tetra­methyl­pyrroline-3-formate (Bode et al., 2008[Bode, E. B., Plackmeyer, J., Prisner, T. F. & Schiemann, O. (2008). J. Phys. Chem. A, 112, 5064-5073.]) and 85 mg (0.12 mmol) of tetra­kis­(tri­phenyl­phosphane)palladium(0) were dissolved in a mixture of 20 ml of tri­ethyl­amine (TEA) and 9 ml of di­methyl­formamide (DMF) giving rise to an orange solution. The solution was heated to 323 K and stirred for 8 h after which the solvents were removed under reduced pressure. The resulting dark-orange powder was dissolved in di­chloro­methane (DCM) and subjected to column chromatography using aluminum oxide (5% water, height 30 cm, diameter 2.3 cm). First, a mixture of DCM and hexane in a 1:2 ratio was used as eluent until all remaining educt, reagents and side products were eluted (approximately 200–300 ml). The column was then eluted using pure DCM to obtain a yellow solution. Removing the solvent yielded the product as a pale-yellow solid (yield: 90%). Crystals suitable for X-ray crystallography were obtained by layering a solution of (1) in benzene with n-hexane.

[Figure 6]
Figure 6
The synthesis of the title compound (1).

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link]. The H atoms were included in calculated positions and treated as riding atoms: C-H = 0.95-0.98 Å with Uiso(H) = 1.5Ueq(C) for methyl H atoms and 1.2Ueq(C) for other H atoms. 16 reflections with bad agreement were omitted from the final refinement cycles.

Table 2
Experimental details

Crystal data
Chemical formula C44H35N4O3·2.5C6H6
Mr 863.03
Crystal system, space group Triclinic, P[\overline{1}]
Temperature (K) 123
a, b, c (Å) 5.7578 (1), 18.0559 (4), 23.3716 (6)
α, β, γ (°) 105.5870 (13), 93.7408 (13), 92.6002 (14)
V3) 2330.41 (9)
Z 2
Radiation type Mo Kα
μ (mm−1) 0.08
Crystal size (mm) 0.28 × 0.20 × 0.08
 
Data collection
Diffractometer Nonius KappaCCD
Absorption correction Multi-scan (SORTAV; Blessing, 1995[Blessing, R. H. (1995). Acta Cryst. A51, 33-38.])
Tmin, Tmax 0.808, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections 74528, 11227, 6356
Rint 0.109
(sin θ/λ)max−1) 0.661
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.071, 0.217, 1.07
No. of reflections 11227
No. of parameters 587
No. of restraints 1
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.33, −0.27
Computer programs: HKL DENZO and SCALEPACK (Otwinowski & Minor 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]), SHELXS97 (Sheldrick,2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), SHELXL2013 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]), OLEX2 (Dolomanov et al., 2009[Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.]) and Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]).

Supporting information


Chemical context top

The title compound (1) was synthesized as a ligand for 3d metal ions in the framework of a pulsed EPR study on metal–nitroxyl model systems. It contains a nitroxyl group and a terpyridine (terpy) group which is capable of taking up metal ions. The title compound resembles compound (3) (4'-{4-[(2,2,5,5-tetra­methyl-N-oxyl-3-pyrrolin-3-yl)ethynyl]phenyl}-2,2':6',2''-terpyridine), which has an ethynyl­phenyl spacer (Meyer et al., 2015a), compared to the phenyl­ethynylbi­phenyl spacer in the title compound (1). Nitroxyls are of inter­est in various branches of chemistry including magnetochemistry (Rajca et al., 2006; Fritscher et al., 2002), synthetic chemistry (Hoover & Stahl, 2011; Fey et al., 2001) and structural biology (Reginsson & Schiemann, 2011). Terpyridines show pH-dependent luminescence properties which have been analyzed in terms of a pH-dependent cistrans isomerization (Nakamoto, 1960; Fink & Ohnesorge, 1970). Structural investigations in the solid state reveal an exclusive preference for the trans conformation (Fallahpour et al., 1999; Eryazici et al., 2006; Bessel et al., 1992; Grave et al., 2003). Terpyridines have been shown to be versatile ligands for various metal ions (Hogg & Wilkins, 1962; Constable et al., 1999; Narr et al., 2002; Meyer et al., 2015b; Folgado et al., 1990).

Structural commentary top

The molecular structure of the title compound, (1), is shown in Fig. 1. The crystal structure of the di­chloro­methane solvate (2) of the title compound has been reported (Ackermann et al., 2015). However, these authors used a different protocol for the crystallization of (1) and the conformation of (2) differs markedly from the one presented herein, as shown in the structural overlay of the two compounds (Fig. 2). The structural overlay of compounds (1) and (3) also illustrate the differences in their conformations (Fig. 3).

In (1) the terpy group assumes the usual all–trans conformation (Meyer et al., 2015a; Fallahpour et al., 1999; Eryazici et al., 2006; Bessel et al., 1992; Grave et al., 2003). It is essentially planar with the two outer rings B (N3/C35–C39) and C (N4/C40–C44) being inclined to the central pyridine ring A (N2/C30–C34) by 8.70 (15) and 14.55 (14)°, respectively. The conformation of the nitroxyl group in (1) is similar to that found in (3), with a planar pyrroline (N1/C1–C4) ring assuming an angle of 72.61 (15)° to the central pyridine ring A [see also Margraf et al. (2009) and Schuetz et al. (2010)]. In (3) this dihedral angle is 88.44 (7)°, while in (2) the same dihedral angle is 21.6 (2)°.

The N-oxylpyrroline-3-formate subunit is linked by a rigid spacer, consisting of a 4,4'bi­phenyl­ene, an ethynylene and a p-phenyl­ene group, to the terpy subunit. The intra­molecular separation of the nitroxyl and the terpy group is 25.044 (3) Å (measured between O1 and N2). The three phenyl groups within the spacer are nearly coplanar, with dihedral angles between the rings of 4.00 (16)°, for rings D (C10–C15) and E (C16–C21), and 3.42 (15)° for rings E and F (C24–C29). Compared to the structure of (3), the spacer is closer to coplanarity to the central pyridine ring: dihedral angle A/D is 24.48 (14)°, compared to 51.36 (7)° in (3). The ethynylene group is slightly bent as in (3), with angle C19–C22–C23 = 174.6 (3) and C22–C23–C24 = 177.8 (3)°. There are short C—H···N contacts in the molecule of 2.48 Å (H31···N3) and 2.49 Å (H34···N4). The same short contacts are also observed in (3). Such contacts have been classified as hydrogen bonds by Murguly et al. (1999).

Supra­molecular features top

In the crystal of (1), Fig. 4, molecules form layers which are nearly coplanar with the (011) plane. Neighbouring layers differ in the orientation of the molecules and each layer is separated by layers of solvent molecules. This arrangement possibly leads to favorable dispersive inter­actions although only one short C—H···π contact is observed between the solvent molecules and molecules of (1) (Table 1). Short ππ contacts are observed between the C rings of neighbouring molecules and between the B and C rings (Fig. 5). The centroid-to-centroid distances are 3.678 (2) and 3.8915 (18) Å, respectively, and can be classified as slipped face-to-face π-inter­actions (Janiak, 2000).

Within the planes, there are weak C—H···O hydrogen bonds between the nitroxyl-O atom and the para-hydrogen atom of pyridine ring B (Table 1). Furthermore, two weak hydrogen bonds per molecule are formed between pairs of layers (Table 1). One of these hydrogen bonds involves the nitroxyl O atom and a hydrogen atom of a methyl group of a molecule from a neighboring layer. The other hydrogen bond is formed between the carbonylic O atom of the carboxyl­ate group and a meta-hydrogen atom of one of the outer pyridine rings of a molecule from a neighboring layer. As the layers are hydrogen bonded pair-wise, the structure can also be described as consisting of double-layers.

It is noteworthy that the arrangement of the molecules of the title compound strongly depends upon the solvents of crystallization. In compound (1), the molecules are arranged in layers and the benzene molecules fill out the channels between the layers formed by the aromatic spacers of the molecule. Close inter­molecule contacts exist only between the functional groups. In the structure of (2) (Ackermann et al., 2015), the solvent of crystallization is di­chloro­methane instead of benzene and molecules are arranged having fourfold rotational site symmetry. The solvent molecules fill out channels between the molecules of (2), as in (1). However, the CH2Cl2 solvent molecules in (2) are in close proximity to the terpyridine groups instead of to the aromatic spacer. Weak hydrogen bonds are formed predominantly involving the O atoms as acceptors and the pyrroline and the pyridine rings as donors, as observed in (2) and (3). The shortest oxygen–oxygen separation between neighboring nitroxyl groups is 4.004 (4) Å. This O···O distance is an important factor determining the strength of through space exchange inter­actions of nitroxyls (Rajca et al. 2006).

Database survey top

The Cambridge Structural Database (CSD, Version 5.36; Groom & Allen, 2014) has not been updated since our presentation of the structure of (2). The CSD query revealed, that non-coordinated terpyridines are arranged in an all-trans conformation, unless they are either protonated, li­thia­ted or cannot assume an all-trans conformation for reasons of steric hindrance.

Synthesis and crystallization top

The synthesis of the title compound (1), is illustrated in Fig. 6. 480 mg (1.45 mmol) of 4'-(4-ethynyl­phenyl)-2,2':6',2''-terpyridine (Grosshenny & Ziessel, 1993), 780 mg (1.69 mmol) of 4'-iodo-p-biphen-4-yl-N- oxyl-2,2,5,5-tetra­methyl­pyrroline-3-formate (Bode et al., 2008) and 85 mg (0.12 mmol) of tetra­kis(tri­phenyl­phosphane)palladium(0) were dissolved in a mixture of 20 ml of tri­ethyl­amine (TEA) and 9 ml of di­methyl­formamide (DMF) giving rise to an orange solution. The solution was heated to 323 K and stirred for 8 h after which the solvents were removed under reduced pressure. The resulting dark-orange powder was dissolved in di­chloro­methane (DCM) and subjected to column chromatography using aluminum oxide (5% water, height 30 cm, diameter 2.3 cm). First, a mixture of DCM and hexane in a 1:2 ratio was used as eluent until all remaining educt, reagents and side products were eluted (approximately 200–300 ml). The column was then eluted using pure DCM to obtain a yellow solution. Removing the solvent yielded the product as a pale-yellow solid (yield: 90%). Crystals suitable for X-ray crystallography were obtained by layering a solution of (1) in benzene with n-hexane.

Refinement top

Crystal data, data collection and structure refinement details are summarized in Table 2. The H atoms were included in calculated positions and treated as riding atoms: C—H = 0.95-0.98 Å with Uiso(H) = 1.5Ueq(C) for methyl H atoms and 1.2Ueq(C) for other H atoms. 16 reflections with bad agreement were omitted from the final refinement cycles.

Related literature top

For related literature, see: Ackermann et al. (2015); Bessel et al. (1992); Bode et al. (2008); Constable et al. (1999); Eryazici et al. (2006); Fallahpour et al. (1999); Fey et al. (2001); Fink & Ohnesorge (1970); Folgado et al. (1990); Fritscher et al. (2002); Grave et al. (2003); Groom & Allen (2014); Grosshenny & Ziessel (1993); Hogg & Wilkins (1962); Hoover & Stahl (2011); Janiak (2000); Margraf et al. (2009); Meyer et al. (2015a, 2015b); Murguly et al. (1999); Nakamoto (1960); Narr et al. (2002); Rajca et al. (2006); Reginsson & Schiemann (2011); Schuetz et al. (2010).

Computing details top

Data collection: HKL DENZO and SCALEPACK (Otwinowski & Minor 1997); cell refinement: HKL SCALEPACK (Otwinowski & Minor 1997); data reduction: HKL DENZO and SCALEPACK (Otwinowski & Minor 1997); program(s) used to solve structure: SHELXS97 (Sheldrick,2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2015); molecular graphics: Olex2 (Dolomanov et al., 2009) and Mercury (Macrae et al., 2008); software used to prepare material for publication: Olex2 (Dolomanov et al., 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound (1), with atom labelling. Displacement ellipsoids are drawn at 50% probability level. The benzene molecules and the H atoms have been omitted for clarity.
[Figure 2] Fig. 2. The structural overlay of compounds (1) and (2) [title compound (1) blue, compound (2 – the dichloromethane solvate (Ackermann et al., 2015) – red].
[Figure 3] Fig. 3. The structural overlay of compounds (1) and (3) [title compound (1) blue, compound (3) – (Meyer et al., 2015a) – green].
[Figure 4] Fig. 4. Crystal packing of the title compound viewed along the a axis. Weak C—H···O hydrogen bonds are shown as dashed lines (see Table 1). H atoms not involved in C—H···O bonds have been omitted for clarity.
[Figure 5] Fig. 5. π-stacking interactions between pyridine rings of neighboring molecules. H atoms have been omitted for clarity.
[Figure 6] Fig. 6. The synthesis of the title compound (1).
4'-{[4-(2,2':6',2''-Terpyridyl-4'-yl)phenyl]ethynyl}biphenyl-4-yl (2,2,5,5-tetramethyl-1-oxyl-3-pyrrolin-3-yl)formate benzene 2.5-solvate top
Crystal data top
C44H35N4O3·2.5C6H6Z = 2
Mr = 863.03F(000) = 912
Triclinic, P1Dx = 1.230 Mg m3
a = 5.7578 (1) ÅMo Kα radiation, λ = 0.71073 Å
b = 18.0559 (4) ÅCell parameters from 12020 reflections
c = 23.3716 (6) Åθ = 1.0–29.1°
α = 105.5870 (13)°µ = 0.08 mm1
β = 93.7408 (13)°T = 123 K
γ = 92.6002 (14)°Plate, yellow
V = 2330.41 (9) Å30.28 × 0.20 × 0.08 mm
Data collection top
Nonius KappaCCD
diffractometer
6356 reflections with I > 2σ(I)
fine slicing φ and ω scansRint = 0.109
Absorption correction: multi-scan
(SORTAV; Blessing, 1995)
θmax = 28.0°, θmin = 1.8°
Tmin = 0.808, Tmax = 1.000h = 77
74528 measured reflectionsk = 2323
11227 independent reflectionsl = 3030
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)] = 0.071Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.217H-atom parameters constrained
S = 1.07 w = 1/[σ2(Fo2) + (0.0715P)2 + 2.806P]
where P = (Fo2 + 2Fc2)/3
11227 reflections(Δ/σ)max < 0.001
587 parametersΔρmax = 0.33 e Å3
1 restraintΔρmin = 0.27 e Å3
Crystal data top
C44H35N4O3·2.5C6H6γ = 92.6002 (14)°
Mr = 863.03V = 2330.41 (9) Å3
Triclinic, P1Z = 2
a = 5.7578 (1) ÅMo Kα radiation
b = 18.0559 (4) ŵ = 0.08 mm1
c = 23.3716 (6) ÅT = 123 K
α = 105.5870 (13)°0.28 × 0.20 × 0.08 mm
β = 93.7408 (13)°
Data collection top
Nonius KappaCCD
diffractometer
11227 independent reflections
Absorption correction: multi-scan
(SORTAV; Blessing, 1995)
6356 reflections with I > 2σ(I)
Tmin = 0.808, Tmax = 1.000Rint = 0.109
74528 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0711 restraint
wR(F2) = 0.217H-atom parameters constrained
S = 1.07Δρmax = 0.33 e Å3
11227 reflectionsΔρmin = 0.27 e Å3
587 parameters
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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.2370 (5)0.01295 (16)0.10190 (12)0.0227 (6)
C20.3869 (5)0.03265 (16)0.15104 (12)0.0228 (6)
C30.4509 (5)0.10465 (16)0.13551 (13)0.0243 (6)
H30.54520.12600.16110.029*
C40.3597 (5)0.14879 (16)0.07364 (13)0.0258 (6)
C50.0104 (5)0.00458 (18)0.11846 (14)0.0299 (7)
H5A0.10950.00360.08250.045*
H5B0.00820.05570.14680.045*
H5C0.07270.03430.13670.045*
C60.3447 (5)0.04980 (17)0.07767 (14)0.0294 (7)
H6A0.50160.03680.06610.044*
H6B0.35440.09910.10850.044*
H6C0.24750.05390.04280.044*
C70.4547 (5)0.02506 (17)0.20817 (13)0.0242 (6)
C80.5527 (5)0.17353 (18)0.03214 (14)0.0319 (7)
H8A0.48320.19710.00850.048*
H8B0.64410.21100.04560.048*
H8C0.65480.12840.03260.048*
C90.1932 (5)0.21795 (18)0.07291 (15)0.0343 (7)
H9A0.06940.20060.09930.051*
H9B0.27990.25620.08670.051*
H9C0.12380.24120.03220.051*
C100.6996 (5)0.04666 (16)0.29676 (13)0.0280 (7)
C110.9052 (6)0.08515 (19)0.29138 (14)0.0358 (7)
H110.96370.07900.25340.043*
C121.0255 (6)0.13289 (19)0.34188 (14)0.0342 (7)
H121.16820.15910.33810.041*
C130.9437 (5)0.14379 (16)0.39818 (13)0.0256 (6)
C140.7358 (5)0.10257 (19)0.40168 (14)0.0330 (7)
H140.67670.10760.43950.040*
C150.6137 (6)0.05439 (19)0.35106 (14)0.0342 (7)
H150.47210.02710.35420.041*
C161.0710 (5)0.19732 (17)0.45189 (13)0.0253 (6)
C171.2858 (6)0.23439 (19)0.44816 (14)0.0360 (8)
H171.34760.22580.41040.043*
C181.4098 (6)0.2824 (2)0.49680 (14)0.0361 (8)
H181.55460.30670.49220.043*
C191.3264 (5)0.29639 (17)0.55323 (13)0.0285 (7)
C201.1098 (6)0.2615 (2)0.55805 (14)0.0366 (8)
H201.04670.27110.59570.044*
C210.9861 (5)0.21278 (19)0.50809 (14)0.0345 (7)
H210.83950.18930.51230.041*
C221.4677 (5)0.34418 (17)0.60378 (14)0.0299 (7)
C231.6001 (5)0.38338 (17)0.64283 (13)0.0288 (7)
C241.7619 (5)0.43207 (17)0.68813 (13)0.0273 (6)
C251.9752 (5)0.45919 (17)0.67281 (13)0.0296 (7)
H252.01130.44550.63240.036*
C262.1331 (5)0.50571 (17)0.71624 (13)0.0285 (7)
H262.27550.52420.70510.034*
C272.0868 (5)0.52596 (15)0.77632 (13)0.0235 (6)
C281.8728 (5)0.49925 (16)0.79124 (13)0.0256 (6)
H281.83680.51290.83170.031*
C291.7132 (5)0.45334 (16)0.74799 (13)0.0265 (6)
H291.56890.43610.75910.032*
C302.2616 (5)0.57301 (15)0.82326 (12)0.0230 (6)
C312.4348 (5)0.62120 (16)0.80997 (13)0.0247 (6)
H312.43640.62780.77100.030*
C322.6059 (5)0.65965 (16)0.85480 (12)0.0241 (6)
C332.4383 (5)0.60956 (16)0.92376 (13)0.0240 (6)
C342.2643 (5)0.56824 (16)0.88191 (12)0.0244 (6)
H342.14820.53700.89310.029*
C352.7986 (5)0.70819 (16)0.84142 (13)0.0249 (6)
C362.9585 (5)0.75177 (17)0.88581 (14)0.0292 (7)
H362.94160.75380.92640.035*
C373.1439 (5)0.79252 (17)0.87052 (14)0.0310 (7)
H373.25530.82280.90040.037*
C383.1634 (6)0.78823 (18)0.81163 (14)0.0337 (7)
H383.28980.81460.79960.040*
C392.9941 (6)0.7444 (2)0.77017 (15)0.0388 (8)
H393.00710.74210.72940.047*
C402.4478 (5)0.60351 (15)0.98644 (12)0.0236 (6)
C412.6483 (5)0.62869 (17)1.02509 (13)0.0279 (6)
H412.78440.64821.01170.033*
C422.6446 (6)0.62468 (18)1.08338 (13)0.0320 (7)
H422.77650.64291.11110.038*
C432.4456 (6)0.59362 (18)1.10055 (14)0.0333 (7)
H432.43840.58981.14020.040*
C442.2573 (6)0.56820 (18)1.05891 (14)0.0324 (7)
H442.12240.54611.07090.039*
C450.4296 (6)0.3900 (2)0.35899 (16)0.0421 (8)
H450.28950.38890.33490.050*
C460.4922 (7)0.4522 (2)0.40689 (16)0.0465 (9)
H460.39340.49380.41630.056*
C470.6977 (7)0.4549 (2)0.44152 (17)0.0527 (10)
H470.74160.49840.47430.063*
C480.8395 (7)0.3934 (3)0.42804 (18)0.0557 (11)
H480.98120.39480.45160.067*
C490.7751 (7)0.3310 (2)0.38076 (17)0.0507 (10)
H490.87130.28870.37170.061*
C500.5700 (7)0.3294 (2)0.34612 (16)0.0446 (9)
H500.52620.28610.31320.053*
C510.7877 (6)0.84135 (17)0.29690 (18)0.101 (2)
H510.68610.87790.31700.121*
C520.9878 (6)0.86602 (14)0.27527 (19)0.0911 (18)
H521.02300.91950.28050.109*
C531.1364 (5)0.8125 (2)0.24592 (18)0.097 (2)
H531.27320.82930.23110.117*
C541.0849 (6)0.73429 (18)0.23820 (15)0.0828 (16)
H541.18640.69770.21810.099*
C550.8848 (6)0.70963 (13)0.25983 (16)0.0666 (13)
H550.84950.65620.25460.080*
C560.7362 (5)0.76315 (19)0.28918 (17)0.0800 (16)
H560.59940.74630.30400.096*
C571.2877 (8)0.0159 (4)0.4782 (3)0.0794 (17)
H571.14030.02700.46290.095*
C581.3994 (10)0.0665 (3)0.5279 (3)0.0766 (15)
H581.32910.11220.54710.092*
C591.6137 (11)0.0509 (4)0.5499 (3)0.0865 (17)
H591.69280.08600.58410.104*
N10.2293 (4)0.08860 (14)0.05611 (11)0.0272 (5)
N22.6094 (4)0.65448 (13)0.91102 (10)0.0233 (5)
N32.8130 (5)0.70501 (16)0.78374 (11)0.0348 (6)
N42.2537 (4)0.57284 (14)1.00265 (11)0.0286 (6)
O10.1208 (4)0.10055 (12)0.00485 (9)0.0358 (5)
O20.4049 (4)0.09116 (12)0.22097 (9)0.0312 (5)
O30.5864 (4)0.00577 (12)0.24535 (9)0.0334 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0219 (14)0.0236 (14)0.0216 (14)0.0012 (11)0.0000 (11)0.0047 (11)
C20.0209 (13)0.0238 (14)0.0228 (14)0.0039 (11)0.0002 (11)0.0064 (11)
C30.0219 (14)0.0243 (15)0.0258 (15)0.0022 (11)0.0030 (11)0.0070 (12)
C40.0251 (14)0.0224 (14)0.0275 (15)0.0001 (12)0.0033 (12)0.0041 (12)
C50.0238 (15)0.0324 (17)0.0300 (17)0.0001 (13)0.0004 (12)0.0036 (13)
C60.0287 (15)0.0310 (16)0.0288 (16)0.0024 (13)0.0009 (12)0.0104 (13)
C70.0213 (14)0.0265 (16)0.0251 (15)0.0022 (12)0.0008 (11)0.0087 (12)
C80.0319 (16)0.0278 (16)0.0333 (17)0.0026 (13)0.0014 (13)0.0040 (13)
C90.0303 (16)0.0278 (16)0.0416 (19)0.0068 (13)0.0038 (14)0.0071 (14)
C100.0353 (16)0.0225 (15)0.0220 (15)0.0013 (13)0.0093 (12)0.0020 (12)
C110.0404 (18)0.0417 (19)0.0226 (16)0.0030 (15)0.0012 (13)0.0052 (14)
C120.0327 (17)0.0395 (18)0.0258 (16)0.0100 (14)0.0016 (13)0.0032 (14)
C130.0272 (15)0.0255 (15)0.0236 (15)0.0014 (12)0.0021 (12)0.0069 (12)
C140.0333 (17)0.0409 (18)0.0224 (16)0.0086 (14)0.0001 (13)0.0070 (13)
C150.0324 (17)0.0391 (18)0.0276 (17)0.0108 (14)0.0033 (13)0.0068 (14)
C160.0239 (14)0.0285 (15)0.0225 (15)0.0017 (12)0.0031 (11)0.0067 (12)
C170.0350 (17)0.045 (2)0.0253 (16)0.0097 (15)0.0019 (13)0.0069 (14)
C180.0294 (16)0.0439 (19)0.0306 (17)0.0140 (14)0.0002 (13)0.0059 (14)
C190.0288 (15)0.0285 (16)0.0254 (15)0.0020 (13)0.0055 (12)0.0048 (12)
C200.0355 (17)0.045 (2)0.0228 (16)0.0098 (15)0.0028 (13)0.0007 (14)
C210.0299 (16)0.0423 (19)0.0264 (16)0.0095 (14)0.0020 (13)0.0027 (14)
C220.0293 (16)0.0295 (16)0.0286 (16)0.0029 (13)0.0015 (13)0.0056 (13)
C230.0276 (15)0.0311 (16)0.0258 (16)0.0013 (13)0.0005 (12)0.0057 (13)
C240.0282 (15)0.0269 (15)0.0247 (15)0.0016 (12)0.0040 (12)0.0054 (12)
C250.0316 (16)0.0307 (16)0.0231 (15)0.0040 (13)0.0009 (12)0.0032 (13)
C260.0265 (15)0.0310 (16)0.0258 (16)0.0039 (12)0.0012 (12)0.0052 (13)
C270.0261 (14)0.0180 (13)0.0249 (15)0.0002 (11)0.0022 (11)0.0047 (11)
C280.0247 (14)0.0276 (15)0.0236 (15)0.0021 (12)0.0014 (11)0.0068 (12)
C290.0247 (14)0.0260 (15)0.0267 (16)0.0027 (12)0.0020 (12)0.0051 (12)
C300.0242 (14)0.0191 (14)0.0244 (15)0.0009 (11)0.0001 (11)0.0046 (11)
C310.0284 (15)0.0235 (14)0.0223 (15)0.0021 (12)0.0013 (12)0.0072 (12)
C320.0274 (15)0.0222 (14)0.0221 (15)0.0009 (12)0.0000 (11)0.0061 (11)
C330.0267 (14)0.0207 (14)0.0250 (15)0.0011 (12)0.0004 (12)0.0073 (12)
C340.0270 (15)0.0223 (14)0.0243 (15)0.0023 (12)0.0030 (12)0.0075 (12)
C350.0292 (15)0.0200 (14)0.0238 (15)0.0009 (12)0.0025 (12)0.0031 (11)
C360.0308 (16)0.0279 (16)0.0271 (16)0.0054 (13)0.0001 (12)0.0061 (13)
C370.0298 (16)0.0253 (15)0.0340 (17)0.0067 (13)0.0000 (13)0.0033 (13)
C380.0341 (17)0.0300 (16)0.0363 (18)0.0069 (13)0.0060 (14)0.0088 (14)
C390.046 (2)0.044 (2)0.0284 (17)0.0093 (16)0.0064 (14)0.0140 (15)
C400.0274 (15)0.0191 (14)0.0237 (15)0.0020 (11)0.0011 (12)0.0055 (11)
C410.0294 (15)0.0266 (15)0.0276 (16)0.0025 (12)0.0009 (12)0.0089 (12)
C420.0380 (17)0.0319 (17)0.0252 (16)0.0019 (14)0.0027 (13)0.0075 (13)
C430.0464 (19)0.0323 (17)0.0230 (16)0.0016 (14)0.0025 (14)0.0108 (13)
C440.0402 (18)0.0302 (16)0.0298 (17)0.0001 (14)0.0037 (14)0.0135 (13)
C450.0380 (19)0.057 (2)0.036 (2)0.0008 (17)0.0055 (15)0.0213 (17)
C460.061 (2)0.045 (2)0.041 (2)0.0118 (18)0.0159 (18)0.0194 (17)
C470.063 (3)0.053 (2)0.037 (2)0.012 (2)0.0112 (18)0.0051 (18)
C480.037 (2)0.090 (3)0.041 (2)0.004 (2)0.0034 (17)0.021 (2)
C490.061 (2)0.060 (3)0.042 (2)0.027 (2)0.0204 (19)0.026 (2)
C500.061 (2)0.040 (2)0.0322 (19)0.0056 (18)0.0072 (17)0.0103 (15)
C510.116 (5)0.067 (3)0.141 (6)0.038 (3)0.062 (4)0.046 (4)
C520.081 (4)0.060 (3)0.152 (6)0.009 (3)0.020 (4)0.059 (4)
C530.073 (3)0.113 (5)0.149 (6)0.026 (3)0.046 (4)0.097 (4)
C540.099 (4)0.069 (3)0.088 (4)0.040 (3)0.028 (3)0.025 (3)
C550.071 (3)0.046 (2)0.084 (3)0.002 (2)0.015 (3)0.025 (2)
C560.061 (3)0.084 (4)0.121 (5)0.013 (3)0.024 (3)0.068 (3)
C570.048 (3)0.109 (4)0.119 (5)0.026 (3)0.031 (3)0.088 (4)
C580.082 (4)0.077 (4)0.095 (4)0.024 (3)0.035 (3)0.057 (3)
C590.093 (4)0.102 (4)0.088 (4)0.014 (4)0.015 (3)0.068 (4)
N10.0300 (13)0.0256 (13)0.0215 (13)0.0024 (10)0.0069 (10)0.0008 (10)
N20.0258 (12)0.0205 (12)0.0223 (12)0.0009 (10)0.0013 (10)0.0043 (10)
N30.0401 (15)0.0379 (15)0.0256 (14)0.0101 (12)0.0026 (11)0.0092 (12)
N40.0301 (13)0.0276 (13)0.0286 (14)0.0056 (11)0.0028 (10)0.0093 (11)
O10.0413 (13)0.0371 (12)0.0238 (11)0.0037 (10)0.0113 (9)0.0023 (9)
O20.0334 (11)0.0276 (12)0.0290 (12)0.0003 (9)0.0022 (9)0.0028 (9)
O30.0464 (13)0.0265 (11)0.0220 (11)0.0053 (10)0.0143 (9)0.0030 (9)
Geometric parameters (Å, º) top
C1—C21.519 (4)C30—C341.395 (4)
C1—C51.526 (4)C31—H310.9500
C1—C61.522 (4)C31—C321.401 (4)
C1—N11.489 (4)C32—C351.483 (4)
C2—C31.329 (4)C32—N21.341 (4)
C2—C71.473 (4)C33—C341.389 (4)
C3—H30.9500C33—C401.496 (4)
C3—C41.498 (4)C33—N21.346 (4)
C4—C81.526 (4)C34—H340.9500
C4—C91.535 (4)C35—C361.384 (4)
C4—N11.479 (4)C35—N31.342 (4)
C5—H5A0.9800C36—H360.9500
C5—H5B0.9800C36—C371.389 (4)
C5—H5C0.9800C37—H370.9500
C6—H6A0.9800C37—C381.370 (4)
C6—H6B0.9800C38—H380.9500
C6—H6C0.9800C38—C391.382 (5)
C7—O21.203 (3)C39—H390.9500
C7—O31.361 (3)C39—N31.338 (4)
C8—H8A0.9800C40—C411.397 (4)
C8—H8B0.9800C40—N41.346 (4)
C8—H8C0.9800C41—H410.9500
C9—H9A0.9800C41—C421.385 (4)
C9—H9B0.9800C42—H420.9500
C9—H9C0.9800C42—C431.383 (4)
C10—C111.375 (4)C43—H430.9500
C10—C151.367 (4)C43—C441.382 (4)
C10—O31.413 (3)C44—H440.9500
C11—H110.9500C44—N41.339 (4)
C11—C121.381 (4)C45—H450.9500
C12—H120.9500C45—C461.371 (5)
C12—C131.394 (4)C45—C501.370 (5)
C13—C141.399 (4)C46—H460.9500
C13—C161.487 (4)C46—C471.381 (6)
C14—H140.9500C47—H470.9500
C14—C151.391 (4)C47—C481.387 (6)
C15—H150.9500C48—H480.9500
C16—C171.398 (4)C48—C491.367 (6)
C16—C211.393 (4)C49—H490.9500
C17—H170.9500C49—C501.382 (5)
C17—C181.365 (4)C50—H500.9500
C18—H180.9500C51—H510.9500
C18—C191.396 (4)C51—C521.3900
C19—C201.397 (4)C51—C561.3900
C19—C221.437 (4)C52—H520.9500
C20—H200.9500C52—C531.3900
C20—C211.388 (4)C53—H530.9500
C21—H210.9500C53—C541.3900
C22—C231.195 (4)C54—H540.9500
C23—C241.435 (4)C54—C551.3900
C24—C251.405 (4)C55—H550.9500
C24—C291.398 (4)C55—C561.3900
C25—H250.9500C56—H560.9500
C25—C261.384 (4)C57—H570.9500
C26—H260.9500C57—C581.370 (8)
C26—C271.399 (4)C57—C59i1.376 (8)
C27—C281.402 (4)C58—H580.9500
C27—C301.489 (4)C58—C591.376 (7)
C28—H280.9500C59—C57i1.376 (8)
C28—C291.383 (4)C59—H590.9500
C29—H290.9500N1—O11.274 (3)
C30—C311.398 (4)O1—O1ii4.004 (4)
C2—C1—C5113.1 (2)C28—C29—C24120.7 (3)
C2—C1—C6114.8 (2)C28—C29—H29119.6
C6—C1—C5110.6 (2)C31—C30—C27121.5 (3)
N1—C1—C298.8 (2)C34—C30—C27121.0 (2)
N1—C1—C5108.9 (2)C34—C30—C31117.4 (2)
N1—C1—C6109.8 (2)C30—C31—H31120.4
C3—C2—C1112.7 (2)C30—C31—C32119.2 (3)
C3—C2—C7125.8 (3)C32—C31—H31120.4
C7—C2—C1121.4 (2)C31—C32—C35120.5 (3)
C2—C3—H3123.3N2—C32—C31123.3 (3)
C2—C3—C4113.4 (3)N2—C32—C35116.2 (2)
C4—C3—H3123.3C34—C33—C40120.2 (2)
C3—C4—C8113.1 (2)N2—C33—C34123.6 (3)
C3—C4—C9112.5 (2)N2—C33—C40116.2 (2)
C8—C4—C9110.9 (2)C30—C34—H34120.3
N1—C4—C399.6 (2)C33—C34—C30119.4 (3)
N1—C4—C8110.1 (2)C33—C34—H34120.3
N1—C4—C9110.2 (2)C36—C35—C32121.6 (3)
C1—C5—H5A109.5N3—C35—C32116.1 (2)
C1—C5—H5B109.5N3—C35—C36122.3 (3)
C1—C5—H5C109.5C35—C36—H36120.3
H5A—C5—H5B109.5C35—C36—C37119.4 (3)
H5A—C5—H5C109.5C37—C36—H36120.3
H5B—C5—H5C109.5C36—C37—H37120.6
C1—C6—H6A109.5C38—C37—C36118.9 (3)
C1—C6—H6B109.5C38—C37—H37120.6
C1—C6—H6C109.5C37—C38—H38120.9
H6A—C6—H6B109.5C37—C38—C39118.1 (3)
H6A—C6—H6C109.5C39—C38—H38120.9
H6B—C6—H6C109.5C38—C39—H39117.9
O2—C7—C2125.5 (3)N3—C39—C38124.2 (3)
O2—C7—O3123.5 (3)N3—C39—H39117.9
O3—C7—C2111.0 (2)C41—C40—C33121.0 (3)
C4—C8—H8A109.5N4—C40—C33116.1 (2)
C4—C8—H8B109.5N4—C40—C41122.9 (3)
C4—C8—H8C109.5C40—C41—H41120.7
H8A—C8—H8B109.5C42—C41—C40118.6 (3)
H8A—C8—H8C109.5C42—C41—H41120.7
H8B—C8—H8C109.5C41—C42—H42120.6
C4—C9—H9A109.5C43—C42—C41118.8 (3)
C4—C9—H9B109.5C43—C42—H42120.6
C4—C9—H9C109.5C42—C43—H43120.7
H9A—C9—H9B109.5C44—C43—C42118.7 (3)
H9A—C9—H9C109.5C44—C43—H43120.7
H9B—C9—H9C109.5C43—C44—H44118.0
C11—C10—O3118.5 (3)N4—C44—C43123.9 (3)
C15—C10—C11121.2 (3)N4—C44—H44118.0
C15—C10—O3120.1 (3)C46—C45—H45120.2
C10—C11—H11120.4C50—C45—H45120.2
C10—C11—C12119.2 (3)C50—C45—C46119.7 (4)
C12—C11—H11120.4C45—C46—H46119.7
C11—C12—H12119.0C45—C46—C47120.5 (4)
C11—C12—C13121.9 (3)C47—C46—H46119.7
C13—C12—H12119.0C46—C47—H47120.3
C12—C13—C14117.0 (3)C46—C47—C48119.5 (4)
C12—C13—C16121.4 (3)C48—C47—H47120.3
C14—C13—C16121.7 (3)C47—C48—H48120.1
C13—C14—H14119.3C49—C48—C47119.9 (4)
C15—C14—C13121.4 (3)C49—C48—H48120.1
C15—C14—H14119.3C48—C49—H49120.0
C10—C15—C14119.3 (3)C48—C49—C50120.0 (4)
C10—C15—H15120.4C50—C49—H49120.0
C14—C15—H15120.4C45—C50—C49120.4 (4)
C17—C16—C13120.9 (3)C45—C50—H50119.8
C21—C16—C13122.5 (3)C49—C50—H50119.8
C21—C16—C17116.6 (3)C52—C51—H51120.0
C16—C17—H17118.8C52—C51—C56120.0
C18—C17—C16122.4 (3)C56—C51—H51120.0
C18—C17—H17118.8C51—C52—H52120.0
C17—C18—H18119.6C51—C52—C53120.0
C17—C18—C19120.8 (3)C53—C52—H52120.0
C19—C18—H18119.6C52—C53—H53120.0
C18—C19—C20118.0 (3)C54—C53—C52120.0
C18—C19—C22119.1 (3)C54—C53—H53120.0
C20—C19—C22122.9 (3)C53—C54—H54120.0
C19—C20—H20119.8C55—C54—C53120.0
C21—C20—C19120.4 (3)C55—C54—H54120.0
C21—C20—H20119.8C54—C55—H55120.0
C16—C21—H21119.1C54—C55—C56120.0
C20—C21—C16121.8 (3)C56—C55—H55120.0
C20—C21—H21119.1C51—C56—H56120.0
C23—C22—C19174.6 (3)C55—C56—C51120.0
C22—C23—C24177.8 (3)C55—C56—H56120.0
C25—C24—C23120.0 (3)C58—C57—H57119.6
C29—C24—C23121.5 (3)C58—C57—C59i120.8 (5)
C29—C24—C25118.5 (3)C59i—C57—H57119.6
C24—C25—H25119.8C57—C58—H58120.1
C26—C25—C24120.4 (3)C57—C58—C59119.8 (5)
C26—C25—H25119.8C59—C58—H58120.1
C25—C26—H26119.4C57i—C59—H59120.3
C25—C26—C27121.2 (3)C58—C59—C57i119.4 (6)
C27—C26—H26119.4C58—C59—H59120.3
C26—C27—C28118.1 (3)C4—N1—C1115.5 (2)
C26—C27—C30121.1 (3)O1—N1—C1122.4 (2)
C28—C27—C30120.8 (3)O1—N1—C4122.1 (2)
C27—C28—H28119.5C32—N2—C33117.1 (2)
C29—C28—C27121.0 (3)C39—N3—C35117.2 (3)
C29—C28—H28119.5C44—N4—C40117.0 (3)
C24—C29—H29119.6C7—O3—C10116.5 (2)
C1—C2—C3—C40.1 (3)C27—C30—C31—C32175.1 (3)
C1—C2—C7—O21.5 (4)C27—C30—C34—C33176.3 (3)
C1—C2—C7—O3179.4 (2)C28—C27—C30—C31158.0 (3)
C2—C1—N1—C40.5 (3)C28—C27—C30—C3424.6 (4)
C2—C1—N1—O1179.4 (2)C29—C24—C25—C260.2 (5)
C2—C3—C4—C8116.6 (3)C30—C27—C28—C29177.8 (3)
C2—C3—C4—C9116.8 (3)C30—C31—C32—C35177.0 (3)
C2—C3—C4—N10.2 (3)C30—C31—C32—N22.0 (4)
C2—C7—O3—C10168.2 (2)C31—C30—C34—C331.2 (4)
C3—C2—C7—O2176.4 (3)C31—C32—C35—C36174.6 (3)
C3—C2—C7—O32.6 (4)C31—C32—C35—N37.8 (4)
C3—C4—N1—C10.4 (3)C31—C32—N2—C330.2 (4)
C3—C4—N1—O1179.4 (2)C32—C35—C36—C37176.1 (3)
C5—C1—C2—C3115.3 (3)C32—C35—N3—C39175.8 (3)
C5—C1—C2—C766.5 (3)C33—C40—C41—C42177.4 (3)
C5—C1—N1—C4118.7 (3)C33—C40—N4—C44178.8 (3)
C5—C1—N1—O162.4 (3)C34—C30—C31—C322.4 (4)
C6—C1—C2—C3116.4 (3)C34—C33—C40—C41164.3 (3)
C6—C1—C2—C761.8 (3)C34—C33—C40—N415.8 (4)
C6—C1—N1—C4120.0 (3)C34—C33—N2—C321.1 (4)
C6—C1—N1—O158.9 (3)C35—C32—N2—C33178.8 (2)
C7—C2—C3—C4178.2 (3)C35—C36—C37—C380.1 (5)
C8—C4—N1—C1118.6 (3)C36—C35—N3—C391.8 (5)
C8—C4—N1—O160.4 (3)C36—C37—C38—C391.2 (5)
C9—C4—N1—C1118.8 (3)C37—C38—C39—N30.8 (5)
C9—C4—N1—O162.3 (4)C38—C39—N3—C350.7 (5)
C10—C11—C12—C130.6 (5)C40—C33—C34—C30178.3 (3)
C11—C10—C15—C140.5 (5)C40—C33—N2—C32179.0 (2)
C11—C10—O3—C780.9 (4)C40—C41—C42—C432.1 (4)
C11—C12—C13—C141.5 (5)C41—C40—N4—C441.1 (4)
C11—C12—C13—C16178.0 (3)C41—C42—C43—C440.4 (5)
C12—C13—C14—C151.5 (5)C42—C43—C44—N41.1 (5)
C12—C13—C16—C174.5 (5)C43—C44—N4—C400.8 (5)
C12—C13—C16—C21176.1 (3)C45—C46—C47—C480.9 (6)
C13—C14—C15—C100.5 (5)C46—C45—C50—C490.6 (5)
C13—C16—C17—C18178.4 (3)C46—C47—C48—C490.0 (6)
C13—C16—C21—C20178.4 (3)C47—C48—C49—C500.6 (6)
C14—C13—C16—C17176.0 (3)C48—C49—C50—C450.3 (5)
C14—C13—C16—C213.4 (5)C50—C45—C46—C471.2 (5)
C15—C10—C11—C120.5 (5)C51—C52—C53—C540.0
C15—C10—O3—C7103.6 (3)C52—C51—C56—C550.0
C16—C13—C14—C15178.0 (3)C52—C53—C54—C550.0
C16—C17—C18—C190.4 (5)C53—C54—C55—C560.0
C17—C16—C21—C201.0 (5)C54—C55—C56—C510.0
C17—C18—C19—C201.8 (5)C56—C51—C52—C530.0
C17—C18—C19—C22176.8 (3)C57—C58—C59—C57i0.5 (8)
C18—C19—C20—C211.8 (5)C59i—C57—C58—C590.5 (8)
C19—C20—C21—C160.4 (5)N1—C1—C2—C30.4 (3)
C21—C16—C17—C181.0 (5)N1—C1—C2—C7178.5 (2)
C22—C19—C20—C21176.7 (3)N2—C32—C35—C366.4 (4)
C23—C24—C25—C26179.5 (3)N2—C32—C35—N3171.3 (3)
C23—C24—C29—C28178.9 (3)N2—C33—C34—C300.5 (4)
C24—C25—C26—C271.0 (5)N2—C33—C40—C4113.7 (4)
C25—C24—C29—C280.8 (4)N2—C33—C40—N4166.2 (2)
C25—C26—C27—C281.5 (4)N3—C35—C36—C371.5 (5)
C25—C26—C27—C30177.1 (3)N4—C40—C41—C422.5 (4)
C26—C27—C28—C290.9 (4)O2—C7—O3—C1010.8 (4)
C26—C27—C30—C3123.4 (4)O3—C10—C11—C12175.9 (3)
C26—C27—C30—C34154.0 (3)O3—C10—C15—C14175.9 (3)
C27—C28—C29—C240.3 (4)
Symmetry codes: (i) x+3, y, z+1; (ii) x, y, z.
Hydrogen-bond geometry (Å, º) top
Cg4, Cg7 and Cg10 are the centroids of pyridine ring N4/C40–C44, spacer ring C24–C29 and benzene ring C54–C59, respectively.
D—H···AD—HH···AD···AD—H···A
C37—H37···O1iii0.952.653.228 (4)120
C38—H38···O2iv0.952.553.485 (4)169
C6—H6C···O1ii0.982.613.499 (4)151
C9—H9B···Cg4v0.962.793.602 (4)140
C14—H14···Cg10vi0.952.883.608 (4)134
C14—H14···Cg10vii0.952.883.608 (4)134
C55—H55···Cg7viii0.952.903.680 (3)140
Symmetry codes: (ii) x, y, z; (iii) x+3, y+1, z+1; (iv) x+4, y+1, z+1; (v) x2, y1, z1; (vi) x1, y, z; (vii) x+2, y, z+1; (viii) x+3, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
Cg4, Cg7 and Cg10 are the centroids of pyridine ring N4/C40–C44, spacer ring C24–C29 and benzene ring C54–C59, respectively.
D—H···AD—HH···AD···AD—H···A
C37—H37···O1i0.952.653.228 (4)120
C38—H38···O2ii0.952.553.485 (4)169
C6—H6C···O1iii0.982.613.499 (4)151
C9—H9B···Cg4iv0.962.793.602 (4)140
C14—H14···Cg10v0.952.883.608 (4)134
C14—H14···Cg10vi0.952.883.608 (4)134
C55—H55···Cg7vii0.952.903.680 (3)140
Symmetry codes: (i) x+3, y+1, z+1; (ii) x+4, y+1, z+1; (iii) x, y, z; (iv) x2, y1, z1; (v) x1, y, z; (vi) x+2, y, z+1; (vii) x+3, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC44H35N4O3·2.5C6H6
Mr863.03
Crystal system, space groupTriclinic, P1
Temperature (K)123
a, b, c (Å)5.7578 (1), 18.0559 (4), 23.3716 (6)
α, β, γ (°)105.5870 (13), 93.7408 (13), 92.6002 (14)
V3)2330.41 (9)
Z2
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.28 × 0.20 × 0.08
Data collection
DiffractometerNonius KappaCCD
diffractometer
Absorption correctionMulti-scan
(SORTAV; Blessing, 1995)
Tmin, Tmax0.808, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
74528, 11227, 6356
Rint0.109
(sin θ/λ)max1)0.661
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.071, 0.217, 1.07
No. of reflections11227
No. of parameters587
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.33, 0.27

Computer programs: HKL DENZO and SCALEPACK (Otwinowski & Minor 1997), HKL SCALEPACK (Otwinowski & Minor 1997), SHELXS97 (Sheldrick,2008), SHELXL2013 (Sheldrick, 2015), Olex2 (Dolomanov et al., 2009) and Mercury (Macrae et al., 2008), Olex2 (Dolomanov et al., 2009).

 

Acknowledgements

The authors thank Professor Dr. A. C. Filippou for providing the X-ray infrastructure. OS thanks the DFG for funding via SFB 813.

References

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Volume 71| Part 10| October 2015| Pages 1245-1249
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