2′‐(4‐Fluoro­phenyl)‐[1,2,3]­triazolo[4′,5′:16,17]­androst‐5‐en‐3β‐ol methanol hemisolvate

The asymmetric unit of the title compound, C₂₅H₃₀FN₃O·0.5CH₃OH, contains four symmetry‐independent steroid and two methanol mol­ecules. The conformations of the independent steroid mol­ecules are very similar. Intermolecular O—H⋯O hydrogen bonds create two independent chains, each of which links two of the independent steroid mol­ecules plus one methanol mol­ecule via a co‐operative O—H⋯O—H⋯O—H pattern. Intermolecular C—H⋯O and C—H⋯F interactions are also observed.     

5‐(2‐Chloro­phenyl­diazenyl)­salicyl­aldehyde and 4‐(2‐chloro­phenyl­diazenyl)‐2‐{[tris­(hydroxy­methyl)­methyl]­amino­methyl­ene}cyclo­hexa‐3,5‐dien‐1(2H)‐one

The mol­ecule of the former title compound, C₁₃H₉ClN₂O₂, (I), is nearly planar, with an intramolecular O⋯O hydrogen bond of 2.692 (2) Å. The latter title compound, C₁₇H₁₈ClN₃O₄, (II), exists in the keto–amine tautomeric form, with a strong intramolecular hydrogen bond of 2.640 (2) Å between the O and N atoms, the H atom being bonded to the N atom. The azo­benzene moieties of both mol­ecules have trans configurations, and the dihedral angle between the planes of the two aromatic rings is 4.1 (1)° in (I) and 9.9 (1)° in (II). The N—H⋯O hydrogen‐bonded rings are almost planar and coupled with the cyclo­hexa­diene rings in (II).     

fac‐Bromo­tri­carbonyl­[2‐(2‐pyridylmethyl)‐2,3‐di­hydro‐1H‐isoindol‐1‐one]­rhenium(I) methanol solvate

The structure of the title compound, fac‐[ReBr(C₁₄H₁₂N₂O)(CO)₃]·CH₄O, consists of neutral mononuclear mol­ecular units of distorted octahedral geometry, with the three carbonyl donors in a facial orientation. The remaining coordination sites are occupied by the Br atom, the pyridine N atom and the ketone O‐atom donor of the ligand. The mol­ecules pack in stacks of antiparallel tapes, with a network of classical (O—H⋯Br) and non‐classical (C—H⋯O) hydrogen bonds between the methanol solvent mol­ecule and the complex mol­ecule.     

1‐(4‐Bromo­phenyl)‐3‐(4‐methyl­phenyl)­prop‐2‐en‐1‐one

In the mol­ecule of the title compound, C₁₆H₁₃BrO, the two benzene rings are rotated in opposite directions with respect to the central C—C=C—C part of the mol­ecule. The phenone O atom deviates from the least‐squares plane of the mol­ecule by 0.300 (3) Å. In the crystal structure, mol­ecules are paired through C—H⋯π interactions. The molecular pairs along [001] are hydrogen bonded through three translation‐related co‐operative hydrogen bonds in the `bay area', forming molecular chains, which are further hydrogen bonded through C—H⋯Br weak interactions, forming (010) molecular layers. In the third direction, there are only weak van der Waals interactions. The co‐operative hydrogen bonds in the `bay area' are discussed briefly.     

[1,3‐Bis(2‐ethoxy­phenyl)imidazolidin‐2‐yl­idene]bromo­(cyclo­octa‐1,5‐diene)­rhodium(I)

The title complex, [RhBr(C₈H₁₂)(C₁₉H₂₂N₂O₂)], has a distorted square‐planar geometry. There are two mol­ecules, A and B, in the asymmetric unit. The Rh—C bond distance between the N‐heterocyclic ligand and the metal atom is 2.039 (2) Å in mol­ecule A and 2.042 (2) Å in mol­ecule B. The angle between the carbene heterocycle and the coordination plane is 87.56 (12)° in mol­ecule A and 87.03 (11)° in mol­ecule B. It is shown that the average Rh—C(COD) (COD is cyclo­octa­diene) distance is linearly dependent on the Rh—C(imidazolidine) distance in this type of compound. This can be ascribed to the steric hindrance produced by the packing. The crystal structure contains intra­molecular C—H⋯O and inter­molecular C—H⋯Br inter­actions.     

(Z)‐6‐{[1,3‐Dihydroxy‐2‐(hydroxy­methyl)propan‐2‐ylamino]methyl­ene}‐2‐methoxy‐4‐[(E)‐o‐tolyl­diazenyl]­cyclo­hexa‐2,4‐dienone

The title compound, C₁₉H₂₃N₃O₅, adopts the keto–amine tautomeric form with the hydr­oxy H atom located on the N atom, where it is involved in a strong intra­molecular N—H⋯O hydrogen bond. The compound exhibits trans geometry with respect to the azo N=N double bond, with a dihedral angle between the two benzene rings of 38.03 (6)°. The packing of the mol­ecules in the crystal structure is determined by O—H⋯O and C—H⋯O hydrogen bonds. A comparison with closely related compounds is given.     

2,6‐Di­methyl‐4‐(phenyl­diazenyl)­phenol

The crystal structure of the title compound, C₁₄H₁₄N₂O, determined at 293 K, shows that the mol­ecule is approximately planar in the solid state and that the aromatic rings have a trans configuration with respect to the azo double bond, as found for other diazene derivatives. The packing can be described as a polymeric arrangement of mol­ecules linked through O—H⋯N and C—H⋯O hydrogen bonds and close contacts. These intermolecular interactions result in the formation of infinite chains parallel to the b axis.     

1‐Methyl‐1‐phenyl‐3‐[1‐hydroxy­imino‐2‐(succinimido)­ethyl]­cyclo­butane

In the title compound, C₁₇H₂₀N₂O₃, the cyclo­butane ring is puckered, with a dihedral angle of 19.11 (15)°. The 1‐phenyl and 3‐[1‐hydroxy­imino‐2‐(succinimido)­ethyl] groups are in cis positions. The mol­ecules are linked by O—H⋯O and C—H⋯π(benzene) interactions, forming a two‐dimensional network.     

Two new polymorphs of di­phenyl(4‐pyridyl)­methyl methacryl­ate

The title compound (D4PyMA), C₂₂H₁₉NO₂, exhibits polymorphism after crystallization by slow evaporation from a binary mixture of chloro­form and hexane. Long needle‐like crystals have an orthorhombic structure (space group Fdd2), with one mol­ecule in the asymmetric unit, while small tablet‐like crystals exhibit a monoclinic crystal structure (space group P2₁/n), in which two independent but chemically identical mol­ecules comprise the asymmetric unit. The bond lengths and angles are normal, while the torsion angles around the –C—O– bond linking the di­phenyl(4‐pyridyl)methyl and methacryl­ate groups show the flexibility of the mol­ecule by way of packing effects. The two polymorphs both contain weak C—H⋯π and C—H⋯O/N contacts but have different conformations.     

Bis(μ‐1,10‐phenanthrolin‐2‐olato‐κ3N,N′:O)­dicopper(I)(Cu—Cu) monohydrate

The crystal structure of the title compound, [Cu₂(C₁₂H₇­N₂O)₂]·H₂O, shows that this dinuclear complex has shorter Cu—N, Cu—O and Cu—Cu distances within the coordination sphere than similar reported complexes. The complex mol­ecule is located on a centre of symmetry and the water mol­ecule is on a twofold axis of the space group C2/c. The discrete complex mol­ecules are extended into a two‐dimensional supramolecular array viaπ–π stacking interactions, intermolecular Cu⋯Cu interactions and C—H⋯O hydrogen bonds.     

2‐Anilinomethyl­ene‐3‐oxobutane­nitrile: an X‐ray and density functional theory study

Mol­ecules of the title compound, C₁₁H₁₀N₂O, are effectively planar. In the crystal structure, they are stabilized primarily by electrostatic inter­actions, as the dipole moment of the mol­ecule is 4.56 D. In addition, the mol­ecules are linked by weak C—H⋯N and C—H⋯O hydrogen bonds. An analysis of bonding conditions in the mol­ecule was carried out using natural bond orbital (NBO) formalism.     

(−)‐3,7‐Dioxo‐5β‐cholanic acid: dual hydrogen‐bonding modes in a diketonic bile‐acid derivative

The asymmetric unit of the title compound, C₂₄H₃₆O₄, contains three mol­ecules, all differing in their side‐chain conformations and all linked by hydrogen bonding confined entirely within a three‐mol­ecule block. One connection is of the acid‐to‐ketone type [O⋯O = 2.7055 (19) Å and O—H⋯O = 180°] and the other involves carboxyl pairing [O⋯O = 2.6485 (18) and 2.6598 (18) Å, and O—H⋯O = 168 and 174°]. Numerous inter­molecular C—H⋯O close contacts connect neighbouring mol­ecules.     

Hydro­gen‐bonding and C—H⋯π interactions in 1,7‐bis(4‐hydroxy‐3‐methoxy­phenyl)­heptane‐3,5‐dione (tetra­hydro­curcumin)

The title compound, C₂₁H₂₄O₆, is the reduced form of curcumin, and exhibits important cosmoceutical properties. The mol­ecule is non‐planar and the benzene rings positioned at the ends of the heptane chain are orthogonally placed, with a dihedral angle of 84.09 (7)° between them. The molecular geometry and H‐atom locations reveal that the `heptane‐3,5‐dione' moiety exists in the keto–enol form, with the hydroxy H atom disordered over two adjacent sites. The packing of the mol­ecules in the lattice is directed by strong O—H⋯O intermolecular hydrogen bonds, which generate two‐dimensional sheets. These sheets are linked by C—H⋯O hydrogen bonds and weak C—H⋯π interactions to develop a three‐dimensional network.     

(2S,RS)‐6‐Phenyl‐1‐(p‐tolyl­sulfinyl)­hexa‐3(E),5(E)‐dien‐2‐ol

The mol­ecule of the title compound, C₁₉H₂₀O₂S, corresponds to a chiral sulfinyldienol with two stereogenic centres, viz. the C atom susbtituted by the hydr­oxy group and the sulfinyl S atom. The mol­ecule displays a V‐shape in the solid state. The dihedral angle defined by the least‐squares planes of the aromatic rings is 72.9 (1)°. The packing pattern exhibits the following inter­molecular hydrogen bonds: one O—H⋯O [H⋯O = 1.98 Å, O⋯O = 2.785 (4) Å and O—H⋯O = 166°] and two C—H⋯O [H⋯O = 2.58 and 2.60 Å, C⋯O = 3.527 (5) and 3.347 (5) Å, and C—H⋯O = 164 and 134°]. These define a chain along b.     

6‐(2‐Chloro­acetamido)­hexa­noic acid

Crystals of the title compound, C₈H₁₄ClNO₃, belong to the space group Cc and are characterized by an asymmetric unit containing two mol­ecules, both with a twisted conformation. The mol­ecular packing is stabilized by N—H⋯O=C hydrogen bonds between the amide groups of mol­ecules with the same conformation. In addition, hydrogen‐bonded cyclic carboxylic acid dimers are established between mol­ecules with a different conformation. The ClCH₂—CONH bond has a cis conformation in order to favour an intra­molecular Cl⋯HN electrostatic inter­action. Weak intra‐ and inter­molecular CH₂⋯O=C inter­actions are also present.     

2,2′‐Methyl­enebis(3‐hydroxy‐5,5‐di­methyl­cyclo­hex‐2‐en‐1‐one)

The title compound, C₁₇H₂₄O₄, crystallizes with two independent mol­ecules, both lying across twofold rotation axes in space group Pccn, in a unit cell whose dimensions closely mimic those of a tetragonal cell. Each mol­ecule contains paired O—H⋯O hydrogen bonds [H⋯O = 1.81 and 1.83 Å, O⋯O = 2.640 (2) and 2.642 (2) Å, and O—H⋯O = 168 and 162°].     

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.     

1,2,4,5‐Tetrakis(2‐vinyl­pyridyl)­benzene–di­chloro­methane (1/2)

The title compound, C₃₄H₂₆N₄·2CH₂Cl₂, lies about an inversion center. The solvent mol­ecules interact with the benzene mol­ecule both through C—H⃛N hydrogen bonding to span pyridine N atoms of adjacent vinyl groups, possibly stabilizing the rotational conformation observed, and through a π interaction between a dichloromethane Cl atom and a pyridyl ring C—C bond of a c‐glide‐related mol­ecule. The benzene mol­ecules form stacks along the a axis such that two of the four olefin groups are properly oriented for photoreactivity (2+2 cyclo­dimerization).     

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.     

C—H⋯π, π–π and C—H⋯Cl interactions in chloro‐substituted Schiff bases and 4‐chloro‐N‐[4‐(di­methyl­amino)­benzyl­idene]­aniline

Molecular packing analyses were carried out on 15 crystal data sets of chloro‐substituted Schiff bases, including that of the title compound, C₁₅H₁₅ClN₂. C—H⋯π and π–π interactions play a major role in the molecular self‐assembly in the crystal. The former interactions favor mol­ecules assembling into a screw, with a non‐centrosymmetric crystal structure. When the molecular dipole is small, π–π interactions favor a parallel, but not usually antiparallel, mode of packing. Weak C—H⋯X hydrogen bonds (X = Cl or Br) and X⋯X interactions seem to be a secondary driving force in packing. The title mol­ecule takes the trans form and the two benzene rings are twisted around the central linkage in opposite directions. In the crystal structure, mol­ecules interact through C—H⋯π and π–π interactions, forming a `dimer' and further forming double chains along [001]. The double chains are extended along [10] through C—H⋯Cl hydrogen bonds, forming double layers in (010). In the third direction, there are only ordinary, weaker, van der Waals interactions, which explains the crystal habit (i.e. thin plate).