(E)‐(4‐Hydroxyphenyl)(4‐nitrophenyl)diazene, (E)‐(4‐methoxyphenyl)(4‐nitrophenyl)diazene and (E)‐[4‐(6‐bromohexyloxy)phenyl](4‐cyanophenyl)diazene

Syntheses and X‐ray structural investigations have been carried out for (E)‐(4‐hydroxy­phenyl)(4‐nitro­phenyl)­diazene, C₁₂H₉N₃O₃, (Ia), (E)‐(4‐methoxy­phenyl)(4‐nitro­phenyl)­diazene, C₁₃H₁₁N₃O₃, (IIIa), and (E)‐[4‐(6‐bromo­hexyl­oxy)­phenyl](4‐cyano­phenyl)­diazene, C₁₉H₂₀BrN₃O, (IIIc). In all of these compounds, the mol­ecules are almost planar and the azo­benzene core has a trans geometry. Compound (Ia) contains four and compound (IIIc) contains two independent mol­ecules in the asymmetric unit, both in space group P (No. 2). In compound (Ia), the independent mol­ecules are almost identical, whereas in crystal (IIIc), the two independent mol­ecules differ significantly due to different conformations of the alkyl tails. In the crystals of (Ia) and (IIIa), the mol­ecules are arranged in almost planar sheets. In the crystal of (IIIc), the mol­ecules are packed with a marked separation of the azo­benzene cores and alkyl tails, which is common for the solid crystalline precursors of mesogens.     

3‐(4‐Acetyl­phenyl)‐1‐(4‐nitro­phenyl)­triazene

The crystal structure of the title compound, C₁₄H₁₂N₄O₃, shows that the stereochemistry about the N=N double bond of the N=N—N(H) moiety is trans. The whole mol­ecule is almost planar (r.m.s. deviation = 0.0654 Å), the interplanar angle between the phenyl rings being 0.7 (1)° and the largest interplanar angle being that between the phenyl ring and the nitro group of the 4‐nitro­phenyl substituent [11.5 (2)°]. Intermolecular N—H⋯O interactions between mol­ecules related by translation give rise to chains along the [110] and [10] directions, and these chains are held together by N⋯O π–π interactions. An unequal distribution of the double‐bond character among the N atoms suggests a delocalization of π electrons over the diazo­amine group and the adjacent aryl substituents.     

Ethyl N‐[2‐(hydroxy­acetyl)­phenyl]­carbamate,ethyl N‐[2‐(hydroxy­acetyl)‐4‐iodo­phenyl]­carbamate and ethyl N‐[2‐(hydroxy­acetyl)‐4‐methyl­phenyl]­carbamate

In ethyl N‐[2‐(hydroxy­acetyl)phenyl]carbamate, C₁₁H₁₃NO₄, all of the non‐H atoms lie on a mirror plane in the space group Pnma; the mol­ecules are linked into simple chains by a single C—H⋯O hydrogen bond. The mol­ecules of ethyl N‐[2‐(hydroxy­acetyl)‐4‐iodo­phenyl]carbamate, C₁₁H₁₂INO₄, are linked into sheets by a combination of O—H⋯I and C—H⋯O hydrogen bonds and a dipolar I⋯O contact. Ethyl N‐­[2‐(hydroxy­acetyl)‐4‐methyl­phenyl]carbamate, C₁₂H₁₅NO₄, crystallizes with Z′ = 2 in the space group P; pairs of mol­ecules are weakly linked by an O—H⋯O hydrogen bond and these aggregates are linked into chains by two independent aromatic π–π stacking inter­actions.     

4‐Methyl‐N‐[2‐(p‐tolylsulfanyl)phenyl]benzene­sulfonamide

The title compound, C₂₀H₁₉NO₂S₂, is formed by a palladium–copper‐catalyzed reaction between 4‐methyl‐N‐[2‐(prop‐2‐ynyl­sul­fanyl)­phenyl]­benzene­sul­fon­amide and p‐iodo­toluene. The mol­ecules contain three essentially planar parts, namely an amino­thio­phenol moiety (A), a toluene­sulfone moiety excluding the oxo ligands (B) and a tolyl group (C), approximately orthogonal to each other; the dihedral angles A/B, A/C and B/C are 111.6 (1), 89.3 (1) and 101.4 (1)°, respectively. Intermolecular N—H?O hydrogen bonds link the mol­ecules into infinite one‐dimensional chains.     

(Z)‐2‐(3‐Methoxy­benzyl­idene)‐1‐aza­bicyclo­[2.2.2]octan‐3‐one

The crystal structure of the title compound, C₁₅H₁₇NO₂, contains two nearly identical but crystallographically independent mol­ecules, each with a double bond connecting an aza­bicyclic ring system to a 3‐methoxy­benzyl­idene moiety. The space group is triclinic P. The benzene ring is twisted by 18.44 (5) and 22.35 (4)° with respect to the plane of the double bond connected to the azabicyclic ring system for the two mol­ecules. In addition to C—H⋯π inter­actions, mol­ecules are held together in the solid state by van der Waals inter­actions.     

Bis{1‐[N‐(2‐methoxy­phenyl)imino­methyl]naphthalen‐2(1H)‐onato‐κ3O,N,O′}zinc(II) ethanol solvate

In the crystal structure of the title compound, [Zn(C₁₈H₁₄NO₂)₂]·C₂H₆O, the Zn atom displays a highly distorted octa­hedral coordination involving the O and N atoms of two mol­ecules of the Schiff base 1‐[N‐(2‐methoxy­phenyl)imino­methyl]naphthalen‐2(1H)‐one, which acts as an O,N,O′‐tridentate ligand. The ethanol mol­ecule is bound to the methoxy group of one ligand mol­ecule via a hydrogen bond.     

N‐(4‐Methoxy­benzyl­idene)‐N′‐(2‐pyridyl)­hydrazine

Molecules of the title compound (alternative name p‐methoxybenzaldehyde 2‐pyridyl­hydrazone), C₁₃H₁₃N₃O, adopt an E configuration about the azomethine C=N double bond. Molecules are almost planar, the dihedral angle between the pyridine and methoxy­phenyl rings being only 6.19 (12)°. Pairwise N—H⃛N hydrogen bonds [R(8) in graph‐set notation] link centrosymmetrically related mol­ecules into discrete pairs.     

N‐(2‐Carboxy­benzoyl)‐l‐leucine methyl ester

The title compound (with the systematic name 2‐{[(1S)‐1‐(methoxy­carbonyl)‐3‐methyl­butyl]amino­carbonyl}benzoic acid), C₁₅H₁₉NO₅, crystallizes in the monoclinic space group P2₁, with two independent mol­ecules per asymmetric unit. The most notable difference between the two mol­ecules is in the dihedral angles between the planes of the carboxyl group and the benzene ring, which are 3.5 (3) and 25.7 (1)°. This difference may account for the fact that two competing reactions are observed in aqueous solution, namely cyclization to form the imide N‐phthaloyl­leucine and hydrolysis of N‐(2‐carboxy­benzoyl)‐l ‐leucine methyl ester to phthalic acid and leucine.     

Mono­alkyl­ated 4′‐aryl‐substituted terpyridines

1‐Methyl‐2‐[4‐phenyl‐6‐(pyridinium‐2‐yl)­pyridin‐2‐yl]­pyridinium diperchlorate, C₂₂H₁₉N₃²⁺·2ClO₄⁻, (I), and 2‐[4‐(methoxy­phenyl)‐2,2′‐bipyridin‐6‐yl]‐1‐methyl­pyridinium iodide, C₂₃H₂₀N₃O⁺·I⁻, (II), both crystallize in the monoclinic space group P2₁/c. In contrast with the monocharged mol­ecule of (II), the doubly charged mol­ecule of (I) contains an additional protonated pyridine ring. One of the two perchlorate counter‐anions of (I) interacts with the cation of (I) via an N—H⋯O hydrogen bond. In (II), two mol­ecules related by a centre of symmetry are connected by weak π–π interactions, forming dimers in the crystal structure.     

2‐Meth­oxy‐4‐[(5‐oxo‐2‐phenyl‐4,5‐dihydro‐1,3‐oxazol‐4‐yl­idene)meth­yl]­phenyl 4‐methyl­benzene­sulfonate

Mol­ecules of the title compound, C₂₄H₁₉NO₆S, adopt the Z configuration and have a distorted tetra­hedral geometry around the S atom. The oxazolone, 2‐phenyl and methoxy­phenyl rings are approximately coplanar. The C atom between the methoxy­phenyl and oxazolone rings displays a distorted trigonal bonding geometry. Pairs of mol­ecules are linked into dimers through weak C—H⋯O hydrogen bonds.     

Di‐μ‐chloro‐bis­{bis­[2,5‐bis­(4‐methoxy­phenyl)‐1,3,4‐oxadiazole‐κ2C2′,N]iridium(III)] dichloro­methane disolvate

In the title compound, [Ir₂(C₁₆H₁₃N₂O₃)₄Cl₂]·2CH₂Cl₂, the two Ir atoms, 3.7075 (6) Å apart, are bridged by two Cl atoms which straddle a twofold axis of rotation through the two Ir atoms. Each Ir centre resides in a distorted octa­hedral environment completed by two chelating 2,5‐bis­(4‐methoxy­phenyl)‐1,3,4‐oxadiazole ligands, with trans‐N—N and cis‐C—C dispositions. In the stacking structure, there are two types of hydrogen bonds, involving the meth­oxy substitutent, an N atom of the oxadiazole ring and the dichloro­methane solvent mol­ecules.     

Two (Z)‐N‐aryl‐3‐benzylideneisoindolin‐1‐ones

Two isoindolin‐1‐one derivatives, (Z)‐3‐benzyl­idene‐N‐phenyl­isoindolin‐1‐one, C₂₁H₁₅NO, (II), and (Z)‐3‐benzyl­idene‐N‐(4‐methoxy­phenyl)­isoindolin‐1‐one, C₂₂H₁₇NO₂, (III), were synthesized by the palladium‐catalysed heteroannulation. The mol­ecules of both compounds have a Z configuration. The interplanar angles between the five‐ and six‐membered rings of the isoindolinone moiety in (II) and (III) are 1.66 (11) and 2.26 (7)°, respectively. The phenyl rings at the N‐position in (II) and (III) are twisted out of the C₄N ring plane by 62.77 (11) and 67.10 (7)°, respectively. The substitutions at the N and C‐3 positions of the isoindolinone system have little influence on the molecular dimensions of the resulting compounds.     

4‐Chloro­aceto­phenone [1‐(4‐methoxyphenyl)­ethyl­idene]­hydra­zone

The crystal structure of the title mixed azine, C₁₇H₁₇ClN₂O, contains four independent mol­ecules, A–D, and mol­ecule B is disordered. All four mol­ecules have an N—N gauche conformation, with C—N—N—C torsion angles of 136.5 (4), 137.0 (4), ?134.7 (4) and ?134.7 (4)°, respectively. The phenyl rings are also somewhat twisted with respect to the plane defined by C_ipso and the imine bond. On average, the combined effect of these twists results in an angle of 64.7° between the best planes of the two phenyl rings. Arene–arene double T‐contacts are the dominant intermolecular inter­action. The methoxy‐substituted phenyl ring of one azine mol­ecule interacts to form a T‐contact with the methoxy‐substituted phenyl ring of an adjacent mol­ecule and, similarly, two chloro‐substituted phenyl rings of neighboring mol­ecules interact to form another T‐contact. The only exception is for mol­ecule B, for which the disorder leads to the formation of T‐­contacts between methoxy‐ and chloro‐substituted phenyl rings. The prevailing structural motif of T‐contact formation between like‐substituted arene rings results in a highly dipole‐parallel‐aligned crystal structure.     

Adducts of 1,1,1‐tris(4‐hydroxy­phenyl)­ethane with 1,2‐bis(4‐pyridyl)­ethane and 1,2‐bis(4‐pyridyl)­ethene: continuously interwoven structures in three dimensions

In the adduct 1,2‐bis(4‐pyridyl)­ethane–1,1,1‐tris(4‐hydroxy­phenyl)­ethane (1/2), C₁₂H₁₂N₂·2C₂₀H₁₈O₃, the bipyridyl component lies across an inversion centre in P. The tris‐phenol mol­ecules [systematic name: 4,4′,4′′‐(ethane‐1,1,1‐triyl)­triphenol] are linked by O—H?O hydrogen bonds to form sheets built from R(38) rings, and symmetry‐related pairs of sheets are linked by the bipyridyl mol­ecules via O—H?N hydrogen bonds to form open bilayers. Each bilayer is interwoven with two adjacent bilayers, forming a continuous three‐dimensional structure. In the adduct 1,2‐bis(4‐pyridyl)­ethene–1,1,1‐tris(4‐hydroxy­phenyl)­ethane–methanol (1/1/1), C₁₂H₁₀N₂·C₂₀H₁₈O₃·CH₄O, the mol­ecules are linked by O—H?O and O—H?N hydrogen bonds into three interwoven three‐dimensional frameworks, generated by single spiral chains along [010] and [001] and a triple‐helical spiral along [100].     

Hydro­gen‐bonded assemblages in 2,6‐bis­(hydroxy­methyl)‐4‐R‐phenol,with R = methyl,methoxy, phenoxy and 1‐(4‐methoxy­phenyl)‐1‐methyl­ethyl

Four derivatives of 2,6‐bis­(hydroxy­methyl)­phenol, with various para substituents, have been investigated; these are 2,6‐bis­(hydroxy­methyl)‐4‐methyl­phenol, C₉H₁₂O₃, (I), 2,6‐bis­(hydroxy­methyl)‐4‐methoxy­phenol, C₉H₁₂O₄, (II), 2,6‐bis­(hydroxy­methyl)‐4‐phenoxy­phenol, C₁₄H₁₄O₄, (III), and 2,6‐bis­(hydroxy­methyl)‐4‐[1‐(4‐methoxy­phenyl)‐1‐methyl­ethyl]­phenol, C₁₈H₂₂O₄, (IV). All four structures display hydrogen‐bonding networks resulting in sheets, with possible weak inter‐sheet π–π interactions in one case. In all the structures but one, the mol­ecules form centrosymmetric dimeric subunits held together by two hydrogen bonds between the hydroxy­methyl groups and, in two cases, by probable π–π interactions.     

6‐(4‐Methoxy­benzyl­amino)­purin‐3‐ium chloride

The title compound, C₁₃H₁₄N₅O⁺·Cl⁻, belongs to the group of aromatic cytokinins. These compounds affect a variety of important physiological processes in plants and animals as well as in bacteria, including cell division, differentiation and senescence. The structure consists of a 6‐(4‐methoxy­benzyl­amino)­purinium cation and a Cl⁻ anion. The cation moiety exists as the N3‐protonated N7 tautomer. The cation contains nearly planar benzene and purine ring systems, with a dihedral angle of 77.46 (5)°. The crystal structure is stabilized by N_amino—H⋯N_purine hydrogen bonds connecting two adjacent mol­ecules, thus forming centrosymmetric dimers.     

A new pseudopolymorph of hexa­kis(4‐cyano­phenyl)benzene

The title compound (systematic name: benzene‐4,4′,4′′,4′′′,4′′′′,4′′′′′‐­hexayl­hexa­benzo­nitrile dichloro­methane disolvate), C₄₈H₂₄N₆·2CH₂Cl₂, crystallizes as an inclusion compound during the slow diffusion of methanol into a solution of hexa­kis(4‐cyano­phenyl)­benzene in CH₂Cl₂. The hexa­kis(4‐cyano­phenyl)benzene mol­ecule lies on an axis of twofold rotation in the space group Pbcn. Weak C—H⋯N inter­actions between hexa­kis(4‐cyano­phenyl)benzene mol­ecules define an open network with space for including guests. The resulting structure is a new pseudopolymorph of hexa­kis(4‐cyano­phenyl)benzene. The eight known pseudopolymorphs have few shared architectural features, in part because none of the inter­molecular inter­actions that are present plays a dominant role or forces neighboring mol­ecules to assume particular relative orientations.     

Supramolecular structures of 5‐[3‐(4‐methyl­phenyl)‐ and 5‐[3‐(4‐chloro­phenyl)‐2‐propenyl­idene]‐2,2‐di­methyl‐1,3‐dioxane‐4,6‐dione

2,2‐Di­methyl‐5‐[3‐(4‐methyl­phenyl)‐2‐propenyl­idene]‐1,3‐di­ox­ane‐4,6‐dione, C₁₆H₁₆O₄, crystallizes in the triclinic space group , with two mol­ecules in the asymmetric unit. These mol­ecules and a centrosymmetrically related pair, linked together by weak C—H?O hydrogen bonds, form a tetramer. 5‐[3‐(4‐Chloro­phenyl)‐2‐propenyl­idene]‐2,2‐di­methyl‐1,3‐dioxane‐4,6‐dione, C₁₅H₁₃ClO₄, also crystallizes in the triclinic space group , with one mol­ecule in the asymmetric unit. Centrosymmetrically related mol­ecules are linked together by weak C—H?O hydrogen bonds to form dimers which are further linked by yet another pair of centrosymmetrically related C—H?O hydrogen bonds to form a tube which runs parallel to the a axis.     

3′,4′‐Bis(4‐chloro­phenyl)­spiro­[chroman‐3,5′(4′H)‐isoxazol]‐4‐one

The title compound, C₂₃H₁₅Cl₂NO₃, crystallizes with two independent mol­ecules in the asymmetric unit. The chroman­one moiety consists of a benzene ring fused with a six‐membered heterocyclic ring which adopts a sofa conformation. The five‐membered spiro­isoxazoline ring is in an envelope conformation. The p‐chloro­phenyl rings bridged by the five‐membered ring are nearly perpendicular to each other. The chromanone moiety of one mol­ecule packs into the cavity formed by the p‐chloro­phenyl rings of a second mol­ecule through the formation of C—H?π interactions. The structure is stabilized by weak C—H?O, C—H?Cl and C—H?π interactions.     

1,3‐Bis(4‐nitro­phenyl)­triazene

The structure of the title compound, C₁₂H₉N₅O₄, reveals an almost planar mol­ecule (r.m.s. deviation = 0.061 Å), in which the interplanar angle between the phenyl rings is 5.7 (1)° and the largest interplanar angle is that between the phenyl ring and the nitro group of one of the 4‐nitro­phenyl substituents [8.8 (3)°]. The observed mol­ecular conformation suggests a delocalization of π‐electrons extended over the diazo­amine group and the terminal aryl substituents. Intermolecular N—H⃛O interactions between the twofold screw‐related mol­ecules give rise to helical chains along the [010] direction. Intermolecular C—H⃛O interactions then generate sheets of mol­ecules in the (10) plane, and these sheets are held together by N⃛C and O⃛O π–π interactions.