A structural study of (1RS,2SR,3RS,4SR,5RS)‐2,4‐dibenzoyl‐1,3,5‐triphenylcyclohexan‐1‐ol chloroform hemisolvate and (1RS,2SR,3RS,4SR,5RS)‐2,4‐dibenzoyl‐1‐phenyl‐3,5‐bis(2‐methoxyphenyl)cyclohexan‐1‐ol

(1RS,2SR,3RS,4SR,5RS)‐2,4‐Dibenzoyl‐1,3,5‐triphenylcyclohexan‐1‐ol or (4‐hydroxy‐2,4,6‐triphenylcyclohexane‐1,3‐diyl)bis(phenylmethanone), C₃₈H₃₂O₃, (1), is formed as a by‐product in the NaOH‐catalyzed synthesis of 1,3,5‐triphenylpentane‐1,5‐dione from acetophenone and benzaldehyde. Single crystals of the chloroform hemisolvate, C₃₈H₃₂O₃·0.5CHCl₃, were grown from chloroform. The structure has triclinic (P) symmetry. One diastereomer [as a pair of (1RS,2SR,3RS,4SR,5RS)‐enantiomers] of (1) has been found in the crystal structure and confirmed by NMR studies. The dichoromethane hemisolvate has been reported previously [Zhang et al. (2007). Acta Cryst. E 63 , o4652]. (1RS,2SR,3RS,4SR,5RS)‐2,4‐Dibenzoyl‐3,5‐bis(2‐methoxyphenyl)‐1‐phenylcyclohexan‐1‐ol or [4‐hydroxy‐2,6‐bis(2‐methoxyphenyl)‐4‐phenylcyclohexane‐1,3‐diyl]bis(phenylmethanone), C₄₀H₃₆O₅, (2), is also formed as a by‐product, under the same conditions, from acetophenone and 2‐methoxybenzaldehyde. Crystals of (2) have been grown from chloroform. The structure has orthorhombic (Pca2₁) symmetry. A diastereomer of (2) possesses the same configuration as (1). In both structures, the cyclohexane ring adopts a chair conformation with all bulky groups (benzoyl, phenyl and 2‐methoxyphenyl) in equatorial positions. The molecules of (1) and (2) both display one intramolecular O—H...O hydrogen bond.     

Two methyl 3‐(1H‐pyrazol‐4‐yl)octahydropyrrolo[3,4‐c]pyrrole‐1‐carboxylates form different hydrogen‐bonded sheets

In the molecules of both methyl (1RS,3SR,3aRS,6aSR)‐1‐methyl‐3‐(3‐methyl‐1‐phenyl‐1H‐pyrazol‐4‐yl)‐4,6‐dioxo‐5‐phenyloctahydropyrrolo[3,4‐c]pyrrole‐1‐carboxylate, C₂₅H₂₄N₄O₄, (I), and methyl (1RS,3SR,3aRS,6aSR)‐5‐(4‐chlorophenyl)‐1‐methyl‐3‐(3‐methyl‐1‐phenyl‐1H‐pyrazol‐4‐yl)‐4,6‐dioxooctahydropyrrolo[3,4‐c]pyrrole‐1‐carboxylate, C₂₅H₂₃ClN₄O₄, (II), the two rings of the pyrrolopyrrole fragment are both nonplanar, with conformations close to half‐chair forms. The overall conformations of the molecules of (I) and (II) are very similar, apart from the orientation of the ester function. The molecules of (I) are linked into sheets by a combination of an N—H...π(pyrrole) hydrogen bond and three independent C—H...O hydrogen bonds. The molecules of (II) are also linked into sheets, which are generated by a combination of an N—H...N hydrogen bond and two independent C—H...O hydrogen bonds, weakly augmented by a C—H...π(arene) hydrogen bond.     

Different hydrogen‐bonded structures in three 2‐thienyl‐substituted tetrahydro‐1,4‐epoxy‐1‐benzazepines

The molecules of (2RS,4SR)‐2‐exo‐(5‐bromo‐2‐thienyl)‐7‐chloro‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C₁₄H₁₁BrClNOS, (I), are linked into cyclic centrosymmetric dimers by C—H...π(thienyl) hydrogen bonds. Each such dimer makes rather short Br...Br contacts with two other dimers. In (2RS,4SR)‐2‐exo‐(5‐methyl‐2‐thienyl)‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C₁₅H₁₅NOS, (II), a combination of C—H...O and C—H...π(thienyl) hydrogen bonds links the molecules into chains of rings. A more complex chain of rings is formed in (2RS,4SR)‐7‐chloro‐2‐exo‐(5‐methyl‐2‐thienyl)‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C₁₅H₁₄ClNOS, (III), built from a combination of two independent C—H...O hydrogen bonds, one C—H...π(arene) hydrogen bond and one C—H...π(thienyl) hydrogen bond.     

Five 2‐aryl‐substituted tetrahydro‐1,4‐epoxy‐1‐benzazepines: isolated molecules and hydrogen‐bonded chains and sheets

(2SR,4RS)‐2‐exo‐Phenyl‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C₁₆H₁₅NO, (I), (2SR,4RS)‐2‐exo‐(4‐chlorophenyl)‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C₁₆H₁₄ClNO, (II), and (2SR,4RS)‐2‐exo‐(3‐methylphenyl)‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C₁₇H₁₇NO, (III), all crystallize with Z′ = 2, in the space groups Cc, P2₁/n and P2₁/c, respectively. In each of (II) and (III), the conformations of the two independent molecules are significantly different. The molecules in (I) are linked by C—H...π(arene) hydrogen bonds to form two independent chains, each containing only one type of molecule. The molecules in (II) are linked into sheets by a combination of C—H...O, C—H...(N,O) and C—H...π(arene) hydrogen bonds, all of which link pairs of molecules related by inversion, while in (III), the molecules are linked into sheets by a combination of C—H...N, C—H...O and C—H...π(arene) hydrogen bonds. There are no direction‐specific intermolecular interactions of any kind in the structure of (2SR,4RS)‐7‐bromo‐2‐exo‐phenyl‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C₁₆H₁₄BrNO, (IV), but in the structure of (2SR,4RS)‐2‐exo‐(4‐bromophenyl)‐7‐chloro‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C₁₆H₁₃BrClNO, (V), a combination of one C—H...N hydrogen bond and one C—H...O hydrogen bond links the molecules into sheets of alternating centrosymmetric R²₂(14) and R⁶₆(22) rings. Comparisons are made with the structures of a number of related compounds.     

Four differently substituted 2‐aryl‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepines: hydrogen‐bonded structures in one,two and three dimensions

In (2RS,4SR)‐7‐chloro‐2‐exo‐(2‐chloro‐6‐fluorophenyl)‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C₁₆H₁₂Cl₂FNO, (I), molecules are linked into chains by a single C—H...π(arene) hydrogen bond. (2RS,4SR)‐2‐exo‐(2‐Chloro‐6‐fluorophenyl)‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C₁₆H₁₃ClFNO, (II), is isomorphous with compound (I) but not strictly isostructural with it, as the hydrogen‐bonded chains in (II) are linked into sheets by an aromatic π–π stacking interaction. The molecules of (2RS,4SR)‐7‐methyl‐2‐exo‐(4‐methylphenyl)‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C₁₈H₁₉NO, (III), are linked into sheets by a combination of C—H...N and C—H...π(arene) hydrogen bonds. (2S,4R)‐2‐exo‐(2‐Chlorophenyl)‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C₁₆H₁₄ClNO, (IV), crystallizes as a single enantiomer and the molecules are linked into a three‐dimensional framework structure by a combination of one C—H...O hydrogen bond and three C—H...π(arene) hydrogen bonds.     

Three closely related thienyl‐substituted 1,4‐epoxynaphtho[1,2‐b]azepines: hydrogen‐bonded assembly in one,two and three dimensions

(2R,4S)‐2‐(3‐Methylthiophen‐2‐yl)‐2,3,4,5‐tetrahydro‐1,4‐epoxynaphtho[1,2‐b]azepine, C₁₉H₁₇NOS, (I), crystallizes with a single enantiomer in each crystal, whereas its geometrical isomer (2RS,4SR)‐2‐(5‐methylthiophen‐2‐yl)‐2,3,4,5‐tetrahydro‐1,4‐epoxy‐naphtho[1,2‐b]azepine, (II), and (2RS,4SR)‐2‐(5‐bromothiophen‐2‐yl)‐2,3,4,5‐tetrahydro‐1,4‐epoxynaphtho[1,2‐b]azepine, C₁₈H₁₄BrNOS, (III), both crystallize as racemic mixtures. A combination of one C—H...O hydrogen bond and two C—H...π(arene) hydrogen bonds links the molecules of (I) into a three‐dimensional framework; the molecules of (II) are linked into a C(4)C(4)[R₂²(7)] chain of rings by a combination of C—H...N and C—H...O hydrogen bonds; and in (III), where Z′ = 2, a combination of four C—H...π(arene) hydrogen bonds and two C—H...π(thienyl) hydrogen bonds links the molecules into complex sheets. Comparisons are made with the assembly patterns in some aryl‐substituted 1,4‐epoxynaphtho[1,2‐b]azepines.     

Three tetrahydro‐1,4‐epoxy‐1‐benzazepines carrying pendent heterocyclic substituents: supramolecular structures in zero,one or two dimensions

(2SR,4RS)‐7‐Fluoro‐2‐exo‐(2‐furyl)‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C₁₄H₁₂FNO₂, (I), crystallizes with Z′ = 2 in the space group P2₁/c. A combination of three C—H...O hydrogen bonds and one C—H...N hydrogen bond links the molecules into a complex chain of rings, and pairs of such chains are linked into a tube‐like structure by two C—H...π(arene) hydrogen bonds. There are no hydrogen bonds in the structure of racemic (2SR,4RS)‐2‐exo‐(5‐bromo‐2‐thienyl)‐7‐fluoro‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C₁₄H₁₁BrFNOS, (II), while the molecules of (2S,4R)‐2‐exo‐(5‐bromo‐2‐thienyl)‐7‐trifluoromethoxy‐2,3,4,5‐tetrahydro‐1H‐1,4‐epoxy‐1‐benzazepine, C₁₅H₁₄BrF₃NO₂S, (III), are linked into sheets by a combination of two C—H...O hydrogen bonds and one C—H...π(arene) hydrogen bond. The significance of this study lies in its observation of the wide variation in the patterns of supramolecular aggregation, consequent upon modest changes in the peripheral substituents.     

Three closely‐related cyclohexanols (C35H27X2N3O3; X = F,Cl or Br): similar molecular structures but different crystal structures

Three highly‐substituted cyclohexanol derivatives have been prepared from 2‐acetylpyridine and 4‐halogenobenzaldehydes under mild conditions. (1RS,2SR,3SR,4RS,5RS)‐3,5‐Bis(4‐fluorophenyl)‐2,4‐bis(pyridine‐2‐carbonyl)‐1‐(pyridin‐2‐yl)cyclohexanol, C₃₅H₂₇F₂N₃O₃, (I), (1RS,2SR,3SR,4RS,5RS)‐3,5‐bis(4‐chlorophenyl)‐2,4‐bis(pyridine‐2‐carbonyl)‐1‐(pyridin‐2‐yl)cyclohexanol acetone 0.951‐solvate, C₃₅H₂₇Cl₂N₃O₃·0.951C₃H₆O, (II), and (1RS,2SR,3SR,4RS,5RS)‐3,5‐bis(4‐bromophenyl)‐2,4‐bis(pyridine‐2‐carbonyl)‐1‐(pyridin‐2‐yl)cyclohexanol, C₃₅H₂₇Br₂N₃O₃, (III), all crystallize in different space groups, viz. Pbca, Fdd2 and P, respectively. In compound (II), the acetone molecule is disordered over two sets of atomic sites having occupancies of 0.690 (13) and 0.261 (13). Each of the cyclohexanol molecules contains an intramolecular O—H...N hydrogen bond and their overall molecular conformations are fairly similar. The molecules of (I) are linked by two independent C—H...O hydrogen bonds to form a C(5)C(10)[R₂²(15)] chain of rings, and those of (III) are linked by a combination of C—H...O and C—H...N hydrogen bonds, forming a chain of alternating R₂²(16) and R₂²(18) rings. The cyclohexanol molecules in (II) are linked by a single C—H...N hydrogen bond to form simple C(4) chains and these chains are linked by a π–π stacking interaction to form sheets, to which the disordered acetone molecules are weakly linked via a number of C—H...O contacts.     

4‐(2‐Fluorophenyl)‐6‐(1H‐indol‐1‐yl)‐3‐methyl‐1‐phenyl‐1H‐pyrazolo[3,4‐b]pyridine‐5‐carbonitrile: a chain of rings built from N—H...N,C—H...N and C—H...π(arene) hydrogen bonds

In the title compound, C₂₈H₁₈FN₅, molecules are linked by a combination of N—H...N, C—H...N and C—H...π(arene) hydrogen bonds into complex double chains. The chains enclose cavities, four per unit cell, each of volume ca 102 ų and apparently containing disordered solvent.     

Octyl 1‐(5‐tert‐butyl‐1H‐pyrazol‐3‐yl)‐2‐(4‐chlorophenyl)‐1H‐benzimidazole‐5‐carboxylate: complex sheets built from N—H...N,C—H...N and C—H...O hydrogen bonds

In the title compound, C₂₉H₃₅ClN₄O₂, the bond lengths provide evidence for aromatic delocalization in the pyrazole ring but bond fixation in the fused imidazole ring, and the octyl chain is folded, rather than adopting an all‐trans chain‐extended conformation. A combination of N—H...N, C—H...N and C—H...O hydrogen bonds links the molecules into sheets, in which the hydrogen bonds occupy the central layer with the tert‐butyl and octyl groups arranged on either side, such that the closest contacts between adjacent sheets involve only the octyl groups. Comparisons are made with the supramolecular assembly in some simpler analogues.     

7‐Amino‐5‐methyl‐2‐phenyl‐6‐(phenyldiazenyl)pyrazolo[1,5‐a]pyrimidine crystallizes with Z′ = 2: pseudosymmetry and the formation of complex sheets built from N—H...N and C—H...π(arene) hydrogen bonds

The title compound, C₁₉H₁₆N₆, crystallizes with Z′ = 2 in the space group P2₁/n. The two molecules in the selected asymmetric unit are approximate mirror images of one another; most corresponding pairs of atoms are related by an approximate half‐cell translation along [100]. Each molecule contains an intramolecular N—H...N hydrogen bond and the molecules are linked into complex sheets by a combination of two intermolecular N—H...N and four C—H...π(arene) hydrogen bonds. Comparisons are made with some other 7‐aminopyrazolo[1,5‐a]pyrimidines.     

Cocrystals of 6‐propyl‐2‐thiouracil: N—H...O versus N—H...S hydrogen bonds

In order to investigate the relative stability of N—H...O and N—H...S hydrogen bonds, we cocrystallized the antithyroid drug 6‐propyl‐2‐thiouracil with two complementary heterocycles. In the cocrystal pyrimidin‐2‐amine–6‐propyl‐2‐thiouracil (1/2), C₄H₅N₃·2C₇H₁₀N₂OS, (I), the `base pair' is connected by one N—H...S and one N—H...N hydrogen bond. Homodimers of 6‐propyl‐2‐thiouracil linked by two N—H...S hydrogen bonds are observed in the cocrystal N‐(6‐acetamidopyridin‐2‐yl)acetamide–6‐propyl‐2‐thiouracil (1/2), C₉H₁₁N₃O₂·2C₇H₁₀N₂OS, (II). The crystal structure of 6‐propyl‐2‐thiouracil itself, C₇H₁₀N₂OS, (III), is stabilized by pairwise N—H...O and N—H...S hydrogen bonds. In all three structures, N—H...S hydrogen bonds occur only within R₂²(8) patterns, whereas N—H...O hydrogen bonds tend to connect the homo‐ and heterodimers into extended networks. In agreement with related structures, the hydrogen‐bonding capability of C=O and C=S groups seems to be comparable.     

1‐(2‐Aminophenyl)‐3‐(4‐pyridyl)prop‐2‐en‐1‐one: a three‐dimensional framework structure built from N—H...N,C—H...O and C—H...π(arene) hydrogen bonds

The intramolecular dimensions of the title compound, C₁₄H₁₂N₂O, provide evidence for a polarized electronic structure. The molecule, which is almost completely planar, contains an intramolecular N—H...O hydrogen bond, and the molecules are linked by a combination of N—H...N, C—H...O and C—H...π(arene) hydrogen bonds to form a three‐dimensional framework structure.     

Naphthalene‐1,6‐diol: a three‐dimensional framework built from O—H...O,O—H...π and C—H...O hydrogen bonds

The asymmetric unit of the title compound, C₁₀H₈O₂, contains two practically planar symmetry‐independent molecules linked by one O—H...O hydrogen bond. Molecules are further linked into a three‐dimensional network, which is built from R₆⁶(36), R₆⁶(18), R₆⁶(30) and R₄⁴(26) rings formed by the combined effect of three O—H...O and one C—H...O hydrogen bond. This network is additionally stabilized by an O—H...π interaction.     

5‐Amino‐1‐benzoyl‐3‐methylpyrazole: complex sheets built from N—H...N,C—H...O and C—H...π(arene) hydrogen bonds

Molecules of the title compound [systematic name: (5‐amino‐3‐methylpyrazol‐1‐yl)(phenyl)methanone], C₁₁H₁₁N₃O, contain an intramolecular hydrogen bond. The molecules are linked into sheets by a combination of N—H...N, C—H...O and C—H...π(arene) hydrogen bonds. Comparisons are made with the hydrogen‐bonded structures of some related compounds.     

One‐dimensional C—H...N hydrogen‐bonded polymers in flexible tetrapyridyl systems

In N,N,N′,N′‐tetrakis(2‐pyridylmethyl)propane‐1,3‐diamine, C₂₇H₃₀N₆, (I), and N,N,N′,N′‐tetrakis(2‐pyridylmethyl)butane‐1,4‐diamine, C₂₈H₃₂N₆, (II), the twofold rotational symmetry of (I) favours the formation of a one‐dimensional hydrogen‐bonded polymer with two columns of C—H...N hydrogen bonds, while the inversion symmetry of (II) allows the formation of a one‐dimensional hydrogen‐bonded polymer stabilized by four columns of C—H...N hydrogen bonds. The possible role played by the chain length of the linking alkanediamine in determining the type of supramolecular architecture in this series of compounds is discussed.     

N—H...O and O—H...O hydrogen‐bonded supramolecular networks in 4‐chloroanilinium, 2‐hydroxyanilinium and 3‐hydroxyanilinium hydrogen phthalates

The title salts, 4‐chloroanilinium hydrogen phthalate (PCAHP), C₆H₇ClN⁺·C₈H₅O₄⁻, 2‐hydroxyanilinium hydrogen phthalate (2HAHP), C₆H₈NO⁺·C₈H₅O₄⁻, and 3‐hydroxyanilinium hydrogen phthalate (3HAHP), C₆H₈NO⁺·C₈H₅O₄⁻, all crystallize in the space group P2₁/c. The asymmetric unit of 2HAHP contains two independent ion pairs. The hydrogen phthalate ions of 2HAHP and 3HAHP show a short intramolecular O—H...O hydrogen bond, with O...O distances ranging from 2.3832 (15) to 2.3860 (14) Å. N—H...O and O—H...O hydrogen bonds, together with short C—H...O contacts in PCAHP and 3HAHP, generate extended hydrogen‐bond networks. PCAHP forms a two‐dimensional supramolecular sheet extending in the (100) plane, whereas 2HAHP has a supramolecular chain running parallel to the [100] direction and 3HAHP has a two‐dimensional network extending parallel to the (001) plane.     

Regio‐ and stereospecific assembly of dispiro[indoline‐3,3′‐pyrrolizine‐1′,5′′‐thiazolidines] from simple precursors using a one‐pot procedure: synthesis,spectroscopic and structural characterization,and a proposed mechanism of formation

The synthesis and characterization of three new dispiro[indoline‐3,3′‐pyrrolizine‐1′,5′′‐thiazolidine] compounds are reported, together with the crystal structures of two of them. (3RS,1′SR,2′SR,7a′SR)‐2′‐(4‐Chlorophenyl)‐1‐hexyl‐2′′‐sulfanylidene‐5′,6′,7′,7a′‐tetrahydro‐2′H‐dispiro[indoline‐3,3′‐pyrrolizine‐1′,5′′‐thiazolidine]‐2,4′′‐dione, C₂₈H₃₀ClN₃O₂S₂, (I), (3RS,1′SR,2′SR,7a′SR)‐2′‐(4‐chlorophenyl)‐1‐benzyl‐5‐methyl‐2′′‐sulfanylidene‐5′,6′,7′,7a′‐tetrahydro‐2′H‐dispiro[indoline‐3,3′‐pyrrolizine‐1′,5′′‐thiazolidine]‐2,4′′‐dione, C₃₀H₂₆ClN₃O₂S₂, (II), and (3RS,1′SR,2′SR,7a′SR)‐2′‐(4‐chlorophenyl)‐5‐fluoro‐2′′‐sulfanylidene‐5′,6′,7′,7a′‐tetrahydro‐2′H‐dispiro[indoline‐3,3′‐pyrrolizine‐1′,5′′‐thiazolidine]‐2,4′′‐dione, C₂₂H₁₇ClFN₃O₂S₂, (III), were each isolated as a single regioisomer using a one‐pot reaction involving l ‐proline, a substituted isatin and (Z)‐5‐(4‐chlorobenzylidene)‐2‐sulfanylidenethiazolidin‐4‐one [5‐(4‐chlorobenzylidene)rhodanine]. The compositions of (I)–(III) were established by elemental analysis, complemented by high‐resolution mass spectrometry in the case of (I); their constitutions, including the definition of the regiochemistry, were established using NMR spectroscopy, and the relative configurations at the four stereogenic centres were established using single‐crystal X‐ray structure analysis. A possible reaction mechanism for the formation of (I)–(III) is proposed, based on the detailed stereochemistry. The molecules of (I) are linked into simple chains by a single N—H…N hydrogen bond, those of (II) are linked into a chain of rings by a combination of N—H…O and C—H…S=C hydrogen bonds, and those of (III) are linked into sheets by a combination of N—H…N and N—H…S=C hydrogen bonds.     

Racemic 2‐isopropyl‐3‐(2‐nitrobenzyl)‐1,3‐thiazolidin‐4‐one crystallizes in the space group P212121 with Z′ = 2: two different interpenetrating three‐dimensional frameworks formed by C—H...O hydrogen bonds

rac‐2‐Isopropyl‐3‐(2‐nitrobenzyl)‐1,3‐thiadiazolin‐4‐one, C₁₃H₁₆N₂O₃S, is a rare example of a racemate crystallizing in the space group P2₁2₁2₁, with one molecule each of S and R configurations, whose conformations are almost mirror images, within the asymmetric unit. The molecules of S configuration are linked by two C—H...O hydrogen bonds into a three‐dimensional framework, and the molecules of R configuration are linked by two further C—H...O hydrogen bonds into a different type of three‐dimensional framework; the two frameworks are linked by a fifth C—H...O hydrogen bond.     

Intermolecular C—H...π interactions in 1,5‐diphenyl‐3‐(2‐pyridyl)‐2‐pyrazoline

The title compound, C₂₀H₁₇N₃, is a derivative of 1,3,5‐triaryl‐2‐pyrazoline and can act as an N,N′‐bidentate ligand. This molecule features strong fluorescence that can be explained by an extended pyridyl–C=N—N–phenyl system. The three‐dimensional structure is formed by means of an extended network of weak C—H...π hydrogen bonds supported by π–π interactions.