2‐Amino‐5‐methyl­pyridinium (2‐amino‐5‐methyl­pyridine)trichloro­zincate(II)

The title compound, (C₆H₉N₂)[ZnCl₃(C₆H₈N₂)], consists of one 2‐amino‐5‐methyl­pyridinium cation and one (2‐amino‐5‐methyl­pyridine)trichloro­zincate(II) anion, which are held together by N—H·Cl hydrogen bonds and π–π inter­actions. The cation and the pyridine ligand show similar geometric features, except for the N—C bond lengths. Mol­ecules of the title compound are connected by N—H·Cl hydrogen bonds to form chiral chains; these chains are associated further by C—H·Cl hydrogen bonds to form layers, which are in turn linked by π–π inter­actions.     

Tetra­aqua­(7‐hydroxy‐5‐oxidoflavone‐6‐sulfonato‐κ2O4,O5)nickel(II) dimethyl­formamide solvate monohydrate

In the title compound, [Ni(C₁₅H₈O₇S)(H₂O)₄]·C₃H₇NO·H₂O, the Ni^II cation is chelated by a 7‐hydroxy‐5‐oxidoflavone‐6‐sulfonate ligand through one oxide and one carbonyl O atom, and the sixfold coordination is completed by four aqua ligands. Individual mol­ecules are linked into hydrogen‐bonded dimers by way of five pairs of O—H⋯O hydrogen bonds. These dimers, in turn, determine a three‐dimensional supra­molecular arrangement through a variety of inter­dimeric inter­actions, such as O—H⋯O, C—H⋯O and π–π stacking.     

1‐Acetyl‐3‐ferrocenyl‐5‐methyl‐1H‐pyrazole and 1‐acetyl‐5‐ferrocenyl‐3‐(2‐pyrid­yl)‐1H‐pyrazole

Mol­ecules of 1‐acetyl‐3‐ferrocenyl‐5‐methyl‐1H‐pyrazole, [Fe(C₅H₅)(C₁₁H₁₁N₂O)], form a centrosymmetric dimer generated by a combination of one C—H⋯π(pyrazole) and one C—H⋯π(cyclo­penta­dienyl) inter­action. The dimers are linked by C—H⋯π inter­actions, involving the pyrazole rings as acceptors, into layers parallel to (10). Mol­ecules of 1‐acetyl‐5‐ferrocenyl‐3‐(2‐pyrid­yl)‐1H‐pyrazole, [Fe(C₅H₅)(C₁₅H₁₂N₃O)], are linked by C—H⋯O inter­actions into a chain running in the [010] direction. Two chains of this type passing through each unit cell are connected by O⋯π(pyridyl) inter­actions into an [010] double chain.     

(μ‐2,11‐Dithia­[3.3]paracyclo­phane‐κ2S:S′)bis­[(6‐carboxy­pyridine‐2‐carboxylato‐κ2N,O6)silver(I)]: a mixed‐ligand silver‐based dinuclear compound

In the title complex, [Ag₂(C₇H₄NO₄)₂(C₁₆H₁₆S₂)], each Ag^I atom is trigonally coordinated by one S atom of a 2,11‐dithia­[3.3]paracyclo­phane (dtpcp) ligand, and by one N and one O atom of a 6‐carboxy­pyridine‐2‐carboxylate ligand. Dtpcp acts as a bidentate ligand, bridging two inversion‐related Ag^I atoms to give a dinuclear silver(I) compound. The dinuclear moieties are inter­connected via O—H·O hydrogen bonds to form a two‐dimensional zigzag sheet. Two such sheets are inter­woven viaπ–π inter­actions between pyridine rings, affording an inter­woven bilayer network.     

Bromo­(η4‐cyclo­octa‐1,5‐diene)[1‐(2,3,4,5,6‐penta­fluoro­benz­yl)‐3‐(2,4,6‐trimethyl­benz­yl)benzimidazol‐2‐yl­idene]rhodium(I)

The title complex, [RhBr(C₈H₁₂)(C₂₄H₁₉F₅N₂)], has a distorted pseudo‐square‐planar geometry. The Rh—C bond distance between the N‐heterocyclic ligand and the metal atom is 2.022 (3) Å. The angle between the carbene heterocycle and the coordination plane is 75.60 (11)°. It is shown that the average Rh—C(cyclo­octa­diene) distance is linearly dependent on the Rh—C(imidazole) distance in this type of compound. The crystal structure contains one intra­molecular and two inter­molecular types of C—H⋯F inter­actions, as well as one type of π–π stacking inter­action.     

6‐Phenyl‐3‐(4‐pyrid­yl)‐1,2,4‐triazolo[3,4‐b][1,3,4]thia­diazole

The title compound, C₁₄H₉N₅S, has been synthesized and characterized both spectroscopically and structurally. The triazolo–thia­diazole system, the pyridine ring and the phenyl ring are all planar. The plane of the triazolo–thia­diazole system forms dihedral angles of 1.53 (13) and 7.55 (12)° with the planes of the pyridine and phenyl rings, respectively. In the mol­ecule, there are two intra­molecular inter­actions of types C—H⋯N and C—H⋯S. Inter­molecular C—H⋯N inter­actions involving a phenyl CH group and a triazole N atom lead to the formation of a one‐dimensional chain. In the crystal structure, two types of π–π inter­actions affect the packing of the mol­ecules. In addition, there are inter­molecular non‐bonded S⋯N contacts of 2.870 (2) Å, which may cause steric hindrance.     

Three (E)‐2‐[(bromo­phen­yl)imino­meth­yl]‐4‐methoxy­phenols

The title compounds, (E)‐2‐[(2‐bromo­phenyl)imino­methyl]‐4‐methoxy­phenol, C₁₄H₁₂BrNO₂, (I), (E)‐2‐[(3‐bromo­phenyl)­imino­methyl]‐4‐methoxy­phenol, C₁₄H₁₂BrNO₂, (II), and (E)‐2‐[(4‐bromo­phenyl)imino­methyl]‐4‐methoxy­phenol, C₁₄H₁₂BrNO₂, (III), adopt the phenol–imine tautomeric form. In all three structures, there are strong intra­molecular O—H⋯N hydrogen bonds. Compound (I) has strong inter­molecular hydrogen bonds, while compound (III) has weak inter­molecular hydrogen bonds. In addition to these inter­molecular inter­actions, C—H⋯π inter­actions in (I) and (III), and π–π inter­actions in (I), play roles in the crystal packing. The dihedral angles between the aromatic rings are 15.34 (12), 6.1 (3) and 39.2 (14)° for (I), (II) and (III), respectively.     

1‐Benzyl‐3,3‐dichloro‐1H‐indol‐2(3H)‐one

The title compound, C₁₅H₁₁Cl₂NO, was synthesized from N‐­benzyl­isatin. The compound crystallizes as stacks of mol­ecules running down the c axis. Mol­ecules within each of these stacks inter­act with each other through π–π and C—H⋯π inter­actions, and inter­act with neighbouring stacks through C—H⋯O inter­actions.     

(2‐Meth­oxy‐3‐pyrid­yl)boronic acid

The structure of the title compound, 2‐CH₃O‐C₅H₃N–3‐B(OH)₂ or C₆H₈BNO₃, comprises two crystallographically independent mol­ecules. The molecules are linked to each other by inter­molecular O—H⋯N and C—H⋯O bonds to produce an infinite chain, while a two‐dimensional structure is formed as a result of π–π inter­actions of planar mol­ecules.     

(Z)‐1‐Ferrocenyl‐3‐(3‐hydroxy­anilino)­but‐2‐en‐1‐one and (Z)‐1‐ferrocenyl‐3‐(4‐hydroxy­anilino)­but‐2‐en‐1‐one

The title compounds, both [Fe(C₅H₅)(C₁₅H₁₄NO₂)], crystallize with Z′ = 2 in the centrosymmetric space group P. In each compound, there is an intra­molecular N—H⋯O=C hydrogen bond, and pairs of inter­molecular O—H⋯O=C hydrogen bonds link the mol­ecules into chains, parallel to [10] in the 3‐hydr­oxy compound and parallel to [10] in the 4‐hydr­oxy compound.     

β‐Lapachone

The most remarkable aspect of the crystal structure of the title compound (systematic name: 3,4‐dihydro‐2,2‐dimethyl‐2H‐naphtho[1,2‐b]pyran‐5,6‐dione), C₁₅H₁₄O₃, is that a π‐stacking inter­action is present between the two naphthalene ring systems of symmetry‐related mol­ecules. Apart from these π–π inter­actions, different mol­ecules are held together by weak C—H⋯O hydrogen‐bonding inter­actions.     

(2,9‐Dimethyl‐1,10‐phenanthroline‐κ2N,N′)(pyridine‐2,6‐dicarboxylato‐κ3O2,N,O6)copper(II) trihydrate

The copper(II) centre in the mononuclear title complex, [Cu(C₇H₃NO₄)(C₁₄H₁₂N₂)]·3H₂O, is surrounded by one bidentate 2,9‐dimethyl‐1,10‐phenanthroline (dmphen) ligand and one tridentate pyridine‐2,6‐dicarboxylate ligand, and exhibits a distorted square‐pyramidal geometry. The crystal packing involves both hydrogen‐bonding and π–π inter­actions. The solvent water mol­ecules link monomers to one another through hydrogen‐bonding inter­actions, forming ladder‐like chains in the bc plane. Face‐to‐face and slipped π–π inter­actions also occur between dmphen rings of neighboring mol­ecules and are responsible for inter­chain packing.     

Polymorphic di‐2‐pyridyl ketone 4‐nitro­phenyl­hydrazone (dpknph): the structure of β‐dpknph

A new polymorph of di‐2‐pyridyl ketone 4‐nitro­phenyl­hydrazone [alternative name: N‐(di­pyridin‐2‐ylmethyl­ene)‐N′‐(4‐nitro­phen­yl)hydrazine], C₁₇H₁₃N₅O₂, isolated from the filtrate of a sonicated acetonitrile solution of dpknph and CdCl₂, was found to crystallize in the monoclinic space group P2₁/c, in contrast to the known form which crystallizes in P2₁/n. The non‐coplanar mol­ecules pack in parallel stacks without any inter­molecular hydrogen‐bonding inter­actions. This packing pattern contrasts with the inter­locked inter­digitated packing seen in the previously known polymorph.     

(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.     

Hydrogen bonding and π–π stacking in 7‐{2‐[4‐(4‐methoxy­phen­yl)piperazin‐1‐yl]eth­oxy}‐4‐methyl‐2H‐chromen‐2‐one monohydrate

In the title compound, C₂₃H₂₆N₂O₄·H₂O, the benzopyran ring system is planar. The piperazine ring adopts an almost perfect chair conformation, and the meth­oxy group is coplanar with its parent benzene ring. Hydrogen bonds link two water mol­ecules and two piperazine mol­ecules into tetra­meric units. The adjacent benzopyran moieties within these units also inter­act viaπ–π stacking inter­actions, and a sheet is formed by the propagation of these inter­actions. The bioassay results have shown α₁‐adrenoceptor antagonistic activity through in vitro animal experiments.     

4,4′‐Butane‐1,4‐diylbis[3‐ethyl‐1H‐1,2,4‐triazol‐5(4H)‐one] and 4‐hydr­oxy‐3‐n‐prop­yl‐1H‐1,2,4‐triazol‐5(4H)‐one

The title compounds, C₁₂H₂₀N₆O₂, (I), and C₅H₉N₃O₂, (II), display the characteristic features of 1,2,4‐triazole derivatives. Compound (I) lies about an inversion centre which is at the mid‐point of the central C—C bond. Compound (II) also contains a planar 1,2,4‐triazole ring but differs from (I) in that it has a hydr­oxy group attached to the ring. Mol­ecules of (I) are held together in the crystal structure by inter­molecular N—H⋯O contacts and by weak π–π stacking inter­actions between the 1,2,4‐triazole moieties. Compound (II) contains inter­molecular O—H⋯O and N—H⋯O hydrogen bonds.     

Tris(acetyl­acetonato‐κ2O,O′)(1,10‐phenanthroline‐κ2N,N′)erbium(III)

The title compound, [Er(C₅H₇O₂)₃(C₁₂H₈N₂)], is a mixed‐ligand metal–organic precursor for chemical vapour deposition, with the Er atom being eight‐coordinate. The coordination polyhedron, described as a distorted square anti­prism, is formed by three bidentate (chelating) acetyl­acetonate residues and a phenanthroline ligand in the apical positions. Mol­ecular assembly via C—H⋯O hydrogen bonds generates a sheet structure in the ac plane. Weak co‐operative C—H⋯π inter­actions form mol­ecular dimers and contribute to the stability of the inter­sheet packing. The supra­molecular assembly contains voids which form hydro­phobic porous channels, surrounded by a cluster of dimers.     

The α‐ and β‐epoxides of 3β‐acet­oxy‐5α‐lanost‐9(11)‐en‐7‐one

The structures of 3β‐acet­oxy‐9α,11α‐ep­oxy‐5α‐lanost‐9(11)‐en‐7‐one and 3β‐acet­oxy‐9β,11β‐ep­oxy‐5α‐lanost‐9(11)‐en‐7‐one, C₃₂H₅₂O₄, differ in their respective substituted cyclo­hexa­none rings but adopt similar conformations in the other three rings. In both of the crystal structures, weak inter­molecular C—H⋯O inter­actions are present.     

Two polymorphic forms of N‐(4‐chloro­phenyl)‐5‐[(4‐chlorophenyl)aminomethyl]‐6‐methyl‐2‐phenyl­pyrimidin‐4‐amine

Two polymorphic forms of the title compound, C₂₄H₂₀Cl₂N₄, were obtained and characterized using X‐ray crystal structure analysis. Colourless crystals of polymorph (Ia) were obtained from the oily mother residue. Recrystallization of polymorph (Ia) from an acetone–methanol mixture resulted in pale‐yellow crystals of polymorph (Ib). The major feature distinguishing the two polymorphic forms is their inter­action modes, and hence their packing arrangements. In the crystal structure of polymorph (Ia), there are N—H⋯N hydrogen bonds and also aromatic π–π stacking inter­actions between mol­ecules. The mol­ecules of polymorph (Ib) are linked by N—H⋯Cl hydrogen bonds only.     

The twofold inter­penetrated three‐connected three‐dimensional (10,3)‐net in 2‐amino­ethene‐1,1,2‐tricarbonitrile

In the crystal structure of the title compound, C₅H₂N₄, each mol­ecule is linked by N—H⋯N[triple‐bond]C hydrogen bonds to four other mol­ecules, thus forming a network that can be described as a twofold inter­penetrated three‐connected three‐dimensional (10,3)‐net. The inter­penetrated nets are related by (010) translation. If only inter­molecular hydrogen bonds are taken into account, these nets can be considered as independent. However, the inter­actions between the cyano groups from different nets indicate mutual assistance of the two nets during their formation.