2‐Chloro‐3‐(pyrrolidin‐1‐yl)‐1,4‐naphtho­quinone

The structure of the title compound, C₁₄H₁₂ClNO₂, (I), comprises essentially planar mol­ecules which crystallize in a monoclinic lattice. C—H?O interactions exist to both naphtho­quinone O atoms and the Cl atom.     

2‐Chloro‐3‐morpholino‐1,4‐naphtho­quinone

The structure of the title compound, C₁₄H₁₂ClNO₃, (I), comprises essentially planar mol­ecules stacked parallel to the a axis. C—H?O hydrogen‐bonding interactions exist to both naphtho­quinone O atoms and the Cl atom, but not to the morpholine O atom.     

[η6‐1‐Chloro‐2‐(pyrrolidin‐1‐yl)benzene](η5‐cyclopentadienyl)iron(II) hexafluoridophosphate and (η5‐cyclopentadienyl){2‐[η6‐2‐(pyrrolidin‐1‐yl)phenyl]phenol}iron(II) hexafluoridophosphate

In the complex salt [η⁶‐1‐chloro‐2‐(pyrrolidin‐1‐yl)benzene](η⁵‐cyclopentadienyl)iron(II) hexafluoridophosphate, [Fe(C₅H₅)(C₁₀H₁₂ClN)]PF₆, (I), the complexed cyclopentadienyl and benzene rings are almost parallel, with a dihedral angle between their planes of 2.3 (3)°. In a related complex salt, (η⁵‐cyclopentadienyl){2‐[η⁶‐2‐(pyrrolidin‐1‐yl)phenyl]phenol}iron(II) hexafluoridophosphate, [Fe(C₅H₅)(C₁₆H₁₇NO)]PF₆, (II), the analogous angle is 5.4 (1)°. In both complexes, the aromatic C atom bound to the pyrrolidine N atom is located out of the plane defined by the remaining five ring C atoms. The dihedral angles between the plane of these five ring atoms and a plane defined by the N‐bound aromatic C atom and two neighboring C atoms are 9.7 (8) and 5.6 (2)° for (I) and (II), respectively.     

A spiro‐linked pyrene–naphtho­quinone

The title mol­ecule, 2′‐pyrenyl­spiro­[2,3‐di­hydro‐1H‐cyclo­penta­[b]­naphthalene‐2,5′‐1′,3′‐dioxane]‐4,9‐dione, C₃₂H₂₂O₄, contains an electron‐donating pyrene group spiro‐linked to an electron‐accepting naphtho­quinone. The mol­ecules are V‐shaped in profile and stack to form columns along b with alternating, approximately coplanar, pyrene and naphtho­quinone fragments. Intermolecular contacts within a column are consistent with some degree of π contact and possible long‐range delocalization. Individual columns form a herringbone pattern when the crystal is viewed along b .     

(Z)‐3‐(1H‐Indol‐3‐yl)‐2‐(3‐thienyl)­acrylo­nitrile and (Z)‐3‐[1‐(4‐tert‐butyl­benzyl)‐1H‐indol‐3‐yl]‐2‐(3‐thienyl)­acrylo­nitrile

(Z)‐3‐(1H‐Indol‐3‐yl)‐2‐(3‐thienyl)­acrylo­nitrile, C₁₅H₁₀N₂S, (I), and (Z)‐3‐[1‐(4‐tert‐butyl­benzyl)‐1H‐indol‐3‐yl]‐2‐(3‐thienyl)­acrylo­nitrile, C₂₆H₂₄N₂S, (II), were prepared by base‐catalyzed reactions of the corresponding indole‐3‐carbox­aldehyde with thio­phene‐3‐aceto­nitrile. ¹H/¹³C NMR spectral data and X‐ray crystal structures of compounds (I) and (II) are presented. The olefinic bond connecting the indole and thio­phene moieties has Z geometry in both cases, and the mol­ecules crystallize in space groups P2₁/c and C2/c for (I) and (II), respectively. Slight thienyl ring‐flip disorder (ca 5.6%) was observed and modeled for (I).     

Four bis(1‐chloro‐2,2,4,4‐tetramethyl‐3‐oxocyclobutan‐1‐yl)oligosulfanes

The four oligosulfanes, bis(1‐chloro‐2,2,4,4‐tetra­methyl‐3‐oxo­cyclo­butan‐1‐yl)­disulfane, C₁₆H₂₄Cl₂O₂S₂, (III), 1,3‐bis(1‐chloro‐2,2,4,4‐tetra­methyl‐3‐oxo­cyclo­butan‐1‐yl)­trisulfane, C₁₆H₂₄Cl₂O₂S₃, (V), 1,4‐bis(1‐chloro‐2,2,4,4‐tetra­methyl‐3‐oxo­cyclo­butan‐1‐yl)­tetrasulfane, C₁₆H₂₄Cl₂O₂S₄, (VII), and 1,6‐bis(1‐chloro‐2,2,4,4‐tetra­methyl‐3‐oxo­cyclo­butan‐1‐yl)­hexasul­fane, C₁₆H₂₄Cl₂O₂S₆, (VIII), all have similar geometric parameters, with the C—C bond lengths involving the chloro‐substituted cyclo­butanyl C atom being elongated to about 1.59 Å. There are two mol­ecules in the asymmetric units of the tri‐ and tetrasulfanes, and the mol­ecules in the latter compound have local C₂ symmetry. The mol­ecule of the hexasulfane has crystallographic C₂ symmetry. Most of the cyclo­butanyl rings are not perfectly planar and have slight but varying degrees of distortion towards a flattened tetrahedron. The polysulfane chain in each structure has a helical conformation, with each additional S atom in the chain adding approximately one quarter of a turn to the helix.     

Four (E,Z,E)‐1‐(4‐alkoxy­phen­yl)‐6‐(4‐nitro­phen­yl)hexa‐1,3,5‐trienes

The crystal structures of the four E,Z,E isomers of 1‐(4‐alk­oxy­phen­yl)‐6‐(4‐nitro­phen­yl)hexa‐1,3,5‐triene, namely (E,Z,E)‐1‐(4‐methoxy­phen­yl)‐6‐(4‐nitro­phen­yl)hexa‐1,3,5‐triene, C₁₉H₁₇NO₃, (E,Z,E)‐1‐(4‐ethoxy­phen­yl)‐6‐(4‐nitro­phen­yl)hexa‐1,3,5‐triene, C₂₀H₁₉NO₃, (E,Z,E)‐1‐(4‐nitro­phen­yl)‐6‐(4‐n‐propoxyphen­yl)hexa‐1,3,5‐triene, C₂₁H₂₁NO₃, and (E,Z,E)‐1‐(4‐n‐butoxy­phen­yl)‐6‐(4‐nitro­phen­yl)hexa‐1,3,5‐triene, C₂₂H₂₃NO₃, have been determined. Inter­molecular N⋯O dipole inter­actions between the nitro groups are observed for the meth­oxy derivative, while for the eth­oxy derivative, two adjacent mol­ecules are linked at both ends through N⋯O dipole–dipole inter­actions between the N atom of the nitro group and the O atom of the eth­oxy group to form a supra­molecular ring‐like structure. In the crystal structures of the n‐prop­oxy and n‐but­oxy derivatives, the shortest inter­molecular distances are those between the two O atoms of the alk­oxy groups. Thus, the nearest two mol­ecules form an S‐shaped supra­molecular dimer in these crystal structures.     

1‐(4‐Chloro­phenyl­sulfanyl)‐2‐nitro‐4‐(tri­fluoro­methyl)­benzene and 1‐(4‐chloro­phenyl­sulfanyl)‐4‐nitro‐2‐(tri­fluoro­methyl)­benzene

Two chemical isomers of 3‐nitro­benzotrifluoride, namely 1‐(4‐chloro­phenyl­sulfanyl)‐2‐nitro‐4‐(tri­fluoro­methyl)­benzene, C₁₃H₇ClF₃NO₂S, (I), and 1‐(4‐chloro­phenyl­sulfanyl)‐4‐nitro‐2‐(tri­fluoro­methyl)­benzene, C₁₃H₇ClF₃NO₂S, (II), have been prepared and their crystal structures determined with the specific purpose of forming a cocrystal of the two. The two compounds display a similar conformation, with dihedral angles between the benzene rings of 83.1 (1) and 76.2 (1)°, respectively, but (I) packs in P while (II) packs in P2₁/c, with C—H⋯O interactions. No cocrystal could be formed, and it is suggested that the C—H⋯O associations in (II) prevent intermolecular mixing and promote phase separation.     

Tetra­kis(1‐eth­yl‐1H‐1,2,4‐triazole‐κN4)bis­(nitrato‐κO)copper(II) and bis­(nitrato‐κO)tetra­kis­(1‐prop­yl‐1H‐1,2,4‐triazole‐κN4)copper(II)

The copper(II) environments for tetra­kis­(1‐eth­yl‐1,2,4‐triaz­ole)­dinitratocopper(II), [Cu(NO₃)₂(C₄H₇N₃)₄], and tetrakis­(1‐prop­yl‐1,2,4‐triazole)dinitratocopper(II), [Cu(NO₃)₂(C₅H₉N₃)₄], are distorted square bipyramidal. Both structures are centrosymmetric, with the copper(II) ions located at inversion centers coordinated by four N atoms of four triazole mol­ecules and by two O atoms of two nitrate ions in an elongated octa­hedral geometry. This elongation is a result of the Jahn–Teller effect. The largest distortion is that of the N—Cu—O angles, which differ from 90° by 5.68 (10)° in the eth­yl and 5.59 (8)° in the prop­yl derivative.     

2‐(1,3‐Dithian‐2‐yl)benzaldehyde and N‐{2‐[2‐(1,3‐dioxan‐2‐yl)phenoxy]­ethyl}phthalimide

The crystal structures of two elaborated‐porphyrin precursors have been determined. In the crystalline state, 2‐(1,3‐di­thian‐2‐yl)­benz­aldehyde, C₁₁H₁₂OS₂, has its di­thiane ring in a slightly distorted chair conformation. The mol­ecules pack in anti‐parallel chains. N‐{2‐[2‐(1,3‐Dioxan‐2‐yl)­phenoxy]­ethyl}­phthal­imide, C₂₀H₁₉NO₅, is in a folded conformation. The dihedral angle between the phthal­imide and phenyl planes is 80.07 (3)°. In the crystalline states, mol­ecules stack on top of one another.     

1,3‐Bis(4‐methyl­phen­yl)triazene, 1‐(4‐chloro­phen­yl)‐3‐(4‐fluoro­phen­yl)triazene and 1‐(4‐fluoro­phen­yl)‐3‐(4‐methyl­phen­yl)triazene

The title 4,4′‐disubstituted diphen­yl‐1,3‐triazines, C₁₄H₁₅N₃, (I), C₁₂H₉ClFN₃, (II), and C₁₃H₁₂FN₃, (III), each contain a triazene group (–N=N—NH–) having an extended conformation. The dihedral angles between the two benzene rings in (I), (II) and (III) are 4.3, 3.4 and 6.5°, respectively. The mol­ecules are almost entirely planar, with maximum deviations from the mean planes of 0.1087 (2), −0.1072 (7) and 0.1401 (3) Å, respectively. In each compound, the molecules are linked by N—H⋯N hydrogen bonds to form chains and pack similarly in the crystal structures.     

Isomeric 3‐ and 4‐chloro‐N‐[1‐(1H‐pyrrol‐2‐yl)ethylidene]aniline

The title isomers, namely 3‐chloro‐N‐[1‐(1H‐pyrrol‐2‐yl)ethylidene]aniline, (I), and 4‐chloro‐N‐[1‐(1H‐pyrrol‐2‐yl)ethylidene]aniline, (II), both C₁₂H₁₁ClN₂, differ in the position of the chlorine substitution. Both compounds have the basic iminopyrrole structure, which shows a planar backbone with similar features. The dihedral angle formed by the planes of the pyrrole and benzene rings is 75.65 (7)° for (I) and 86.56 (8)° for (II). The H atom bound to the pyrrole N atom is positionally disordered and partial protonation occurs at the imino N atom in (I), while this phenomenon is absent from the structure of (II). Packing interactions for both compounds include intermolecular N—H...N hydrogen bonds and C—H...π interactions, forming centrosymmetric dimers for both (I) and (II).     

The E and Z isomers of 3‐(benzoxazol‐2‐yl)­prop‐2‐enoic acid

The carboxyl­ic acid group and the double bond are coplanar in (E)‐3‐(benzoxazol‐2‐yl)­prop‐2‐enoic acid, C₁₀H₇NO₃, whereas in isomeric (Z)‐3‐(benzoxazol‐2‐yl)­prop‐2‐enoic acid, also C₁₀H₇NO₃, they are almost orthogonal. In both isomers, a strong O—H⋯N hydrogen bond, with the carboxyl­ic acid group as a donor and the pyridine‐like N atom as an acceptor, and weak C—H⋯O interactions contribute to the observed supramolecular structures, which are completed by π–π stacking interactions between oxazole and benzenoid rings.     

Racemic and chiral 1‐[N‐(chloro­acetyl)carbamoylamino]‐2,3‐dihydro‐1H‐inden‐2‐yl chloroacetate

In the racemic crystals of (1S,2R)‐ or (1R,2S)‐1‐[N‐(chloro­acetyl)­carbamoyl­amino]‐2,3‐di­hydro‐1H‐inden‐2‐yl chloro­acetate, C₁₄H₁₄Cl₂N₂O₄, (I), the enantiomeric mol­ecules form a dimeric structure via the N—H?O cyclic hydrogen bond of the carbamoyl moieties. In the chiral crystals of (—)‐(1S,2R)‐1‐[N‐(chloro­acetyl)­carbamoyl­amino]‐2,3‐di­hydro‐1H‐inden‐2‐yl chloro­acetate, C₁₄H₁₄Cl₂N₂O₄, (II), the N—­H?O intermolecular hydrogen bond forms a zigzag chain around the twofold screw axis. The melting points and calculated densities of (I) and (II) are 446 and 396 K, and 1.481 and 1.445 Mg m^?3, respectively.     

1,4‐Bis(triisopropyl­silyl)buta‐1,3‐diyne and 1,4‐bis­(biphenyl‐4‐yl)buta‐1,3‐diyne

We report the single crystal structures of 1,4‐bis­(triisopropyl­silyl)buta‐1,3‐diyne, C₂₂H₄₂Si₂, and 1,4‐bis­(biphenyl‐4‐yl)buta‐1,3‐diyne, C₂₈H₁₈, the packing in both of which illustrates the versatility of weak C—H⋯π supra­molecular inter­actions in dictating the overall solid‐state structures.     

Two hydrates of 2,6‐bis­(1H‐benzimidazol‐2‐yl)­pyridine

The structures of the mono‐ and sesquihydrates of 2,6‐bis(1H‐benz­imi­da­zol‐2‐yl)­pyridine (bbip) are reported. Phase (I), C₁₉H₁₃N₅·H₂O, has one water and one bbip mol­ecule in the asymmetric unit, while phase (II), C₁₉H₁₃N₅·1.5H₂O, has three water mol­ecules and two bbip mol­ecules in the asymmetric unit. The compounds exhibit very similar molecular geom­etries but different packing organizations, which result from intricate hydrogen‐bonding schemes.     

[2‐(Imidazol‐4‐yl)ethylamine]{[2‐(imidazol‐4‐yl)ethyl][(1‐methylimidazol‐2‐yl)methyl]amine}copper(II) diperchlorate

In the title mononuclear complex, [Cu(C₅H₉N₃)(C₁₀H₁₅N₅)](ClO₄)₂, the Cu^II centre is surrounded by two N‐donor ligands, which impose a square‐pyramidal environment on the metal. The new tridentate ligand [2‐(imidazol‐4‐yl)­ethyl]­[(1‐methyl­imidazol‐2‐yl)­methyl]­amine (HISMIMA) lies in the basal plane, while the hist­amine ligand occupies the apical and one of the basal positions around the Cu^II ion.     

Dichloro­[(3,5‐dimethyl‐1H‐pyrazol‐1‐yl)methane]zinc(II) and di‐μ‐chloro‐bis­{chloro­[(3,5‐dimethyl‐1H‐pyrazol‐1‐yl)methane]cadmium(II)}

The Zn atom in dichloro­[(3,5‐dimethyl‐1H‐pyrazol‐1‐yl)­methane]zinc(II), [ZnCl₂(C₁₁H₁₆N₄)], (I), is tetra­hedrally coordinated by two N atoms from one bis­(3,5‐dimethyl­pyrazol­yl)methane ligand and two terminal Cl atoms. The mol­ecule has no crystallographic symmetry. One H atom of the CH₂ group of the bis­(3,5‐dimethyl­pyrazol­yl)methane ligand inter­acts with a Cl atom of an adjacent mol­ecule to yield inter­molecular C—H⋯Cl contacts, thereby forming a one‐dimensional zigzag chain extending along the b axis. On the other hand, in di‐μ‐chloro‐bis­{chloro­[(3,5‐dimethyl‐1H‐pyrazol‐1‐yl)methane]cadmium(II)}, [Cd₂Cl₄(C₁₁H₁₆N₄)₂], (II), each of the two crystallographically equivalent Cd atoms is penta­coordinated by two N atoms from one bis­(3,5‐dimethyl­pyrazol­yl)methane ligand, and by one terminal and two bridging Cl⁻ anions. The mol­ecule has a crystallographic centre of symmetry located at the mid‐point of the Cd⋯Cd line. One H atom of the CH₂ group of the bis­(3,5‐dimethyl­pyrazolyl)­methane ligand inter­acts with a Cl atom of an adjacent mol­ecule to produce pairwise inter­molecular C—H⋯Cl contacts, thereby affording chains of mol­ecules running along the c axis.     

New succinyl‐spaced pyrazoles: Regioselective synthesis of 1,4‐bis[5‐(trichloromethyl)‐1H‐pyrazol‐1‐yl]butane‐1,4‐diones

The facile and convenient access by a conventional procedure in ethanol as solvent to a new series of succinyl‐spaced pyrazoles including 1,4‐bis[5‐(trichloromethyl)‐5‐hydroxy‐4,5‐dihydro‐1H‐pyrazol‐1‐yl]butane‐1,4‐diones (64–82%) and the respective dehydrated derivatives as 1,4‐bis[5‐(trichloromethyl)‐1H‐pyrazol‐1‐yl]butane‐1,4‐diones in 57–82% yields, from the regioselective cyclocondensation reactions of 4‐substituted 4‐methoxy‐1,1,1‐trichloroalk‐3‐en‐2‐ones with succinic acid dihydrazide, where the 4‐substituents are Me, Ph, 4‐FC₆H₄, 4‐ClC₆H₄, 4‐NO₂C₆H₄, 2‐furyl, and 2‐thienyl, is reported. J. Heterocyclic Chem., 2011.     

Supra­molecular motifs in 1‐(2‐cyano­ethyl)thymine and 1‐(3‐cyano­propyl)­thymine

In both 1‐(2‐cyano­ethyl)thymine [systematic name: 3‐(5‐methyl‐2,4‐dioxo‐1,2,3,4‐tetra­hydro­pyrimidin‐1‐yl)propane­nitrile], C₈H₉N₃O₂, (I), and 1‐(3‐cyano­propyl)thymine [systematic name: 4‐(5‐methyl‐2,4‐dioxo‐1,2,3,4‐tetra­hydro­pyrimidin‐1‐yl)butane­nitrile], C₉H₁₁N₃O₂, (II), the core of the supra­molecular structure is formed by centrosymmetric dimers generated by N—H⋯O hydrogen bonds. Further weak hydrogen bonds of C—H⋯O and C—H⋯N types generate mol­ecular tapes and sheets that resemble those in uracil and its methyl derivatives. The steric hindrance that arises from the cyano­alkyl substituents perturbs the conformations of the tapes and sheets.