(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.     

A supramolecular zigzag chain of organometallic dipoles mediated by PF6− anions

The title compound, (η⁵‐cyclo­penta­dienyl)(4‐nitro­benzo­nitrile‐κN)(trimethyl­phosphine‐κP)(triphenyl­phosphite‐κP)iron(II) hexa­fluoro­phosphate, [Fe(C₅H₅)(C₇H₄N₂O₂)(C₁₈H₁₅O₃P)(C₃H₉P)]PF₆, has been characterized by spectroscopic and X‐ray diffraction in order to evaluate the tuning of the electron density at the metal centre and the extension of the π delocalization on the mol­ecule due to the presence of phosphite and phosphine co‐ligands. The compound crystallizes in the centrosymmetric space group P2₁/c, which destroys the possibility of exhibiting any quadratic non‐linear optical properties. The packing shows a supramolecular zigzag chain of antiparallel cations connected via the PF₆⁻ anions through C—H⋯F^δ− inter­actions, with H⋯F distances ranging from 2.39 to 2.67 Å. Each zigzag chain is composed of isomeric organometallic fragments containing either R or S mol­ecules. These chains are connected through weak inter­molecular C—H⋯C inter­actions, forming a two‐dimensional plane parallel to (101).     

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.     

Bis(3‐amino­pyridine‐κN)(4,4′‐di­methyl‐2,2′‐bipyridine‐κ2N,N′)(per­chlorato‐κO)copper(II) per­chlorate

The title compound, [Cu(ClO₄)(C₅H₆N₂)₂(C₁₂H₁₂N₂)]ClO₄, was prepared by in situ partial ligand substitution between 3‐amino­pyridine and 4,4′‐dimethyl‐2,2′‐bipyridine at room temperature. The central copper(II) ion is five‐coordinated by one bidentate 4,4′‐dimethyl‐2,2′‐bipyridine mol­ecule, two monodentate pyridine‐coordinated 3‐amino­pyridine mol­ecules and one apical O atom from the perchlorate counter‐ion. Inter­molecular N—H⋯O and C—H⋯O hydrogen‐bonding inter­actions form a hydrogen‐bond‐sustained network.     

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.     

catena‐Poly[[[tetra­aqua­zinc(II)]‐μ‐4,4′‐bipyridine] bis­(4‐hydroxy­benzene­sulfonate) trihydrate]

In the title compound, {[Zn(C₁₀H₈N₂)(H₂O)₄](C₆H₅O₄S)₂·3H₂O}_n, the Zn atom, the bipyridine ligand and one of water mol­ecules are located on twofold rotation axes. The Zn atom is coordinated by four O atoms from four water mol­ecules and two N atoms from two 4,4′‐bipyridine mol­ecules in a distorted octa­hedral geometry. The Zn²⁺ ions are linked by the 4,4′‐bipyridine mol­ecules to form a one‐dimensional straight chain propagating along the c axis. The 4‐hydroxy­benzene­sulfonate counter‐ions are bridged by the solvent water mol­ecules through hydrogen bonds to generate a two‐dimensional layer featuring large pores. In the crystal packing, the intra­layer pores form one‐dimensional channels along the c axis, in which the one‐dimensional [Zn(C₁₀H₈N₂)(H₂O)₄]²⁺ chains are encapsulated. Electrostatic inter­actions between cations and anions and extensive hydrogen bonds result in a three‐dimensional supra­molecular structure.     

(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.     

4,5‐Propyl­enedi­thio‐1,3‐di­thiole‐2‐thione and 4,5‐propyl­enedi­thio‐1,3‐di­thiol‐2‐one

4,5‐Propyl­ene­di­thio‐1,3‐di­thiole‐2‐thione, C₆H₆S₅, (I), crystallizes in the centrosymmetric space group P2₁/c. The molecular packing is characterized by pairs of S⋯S intermolecular contacts between neighbouring mol­ecules, which may account for the rather high thermal stablity of the crystal. 4,5‐Propyl­ene­di­thio‐1,3‐di­thiol‐2‐one, C₆H₆OS₄, (II), in which an O atom replaces the terminal S atom of (I), crystallizes in the non‐centrosymmetric polar space group Cc. The packing pattern of (II) indicates that the macropolarization direction is along [101]. Although the packing patterns are qualitatively significantly different, the molecular structures of (I) and (II) are similar, each exhibiting a chair conformation.     

Morpholine‐2,5‐dione

In the title compound, C₄H₅NO₃, the morpholine ring adopts a boat conformation that is distorted towards twist–boat, the boat ends being the two Csp³ atoms of the ring. The mol­ecular packing is stabilized by the establishment of strong inter­molecular NH⋯OC hydrogen bonds, which give rise to centrosymmetric dimers, and a network of weak CH₂⋯OC hydrogen bonds, where each dimer inter­acts with eight neighbouring morpholine­dione rings.     

Hydrogen bonding in meso‐4,5‐diphenyl‐3,6‐diaza­octane‐1,8‐diol: the formation of one‐dimensional linear chains of edge‐fused rings

The molecule of the title compound, C₁₈H₂₄N₂O₂, resides on a crystallographic inversion centre. The mol­ecule adopts a transoid conformation with respect to the central C—C single bond and is in the meso form. A polarimetric study of the compound did not show any optical activity, indicating that the compound is a racemic mixture entirely consistent with the centrosymmetric space group. In the mol­ecule, there is one intra­molecular N—H⋯O inter­action, resulting in the formation of a five‐membered ring. In the crystal structure, inter­molecular O—H⋯N and C—H⋯O inter­actions are also observed. These inter­actions form an R₂²(9) ring and one‐dimensional linear chains of edge‐fused rings running parallel to the [010] direction, which stabilize the crystal packing.     

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.     

catena‐Poly[[[triaqua­cobalt(II)]‐μ‐2,6‐dioxo‐1,2,3,6‐tetra­hydro­pyrimidine‐4‐carboxyl­ato(2–)] 1.72‐hydrate]

The Co^II ion in the title complex {[Co(C₅H₂N₂O₄)(H₂O)₃]·1.72H₂O}_n, has a distorted octa­hedral coordination geometry comprised of three water ligands, one deprotonated pyrimidine N atom and an adjacent carboxyl­ate O atom of one orotate ligand. The sixth coordination site is occupied by an exocyclic O atom from a neighbouring orotate moiety, and through this inter­action a helicoidal chain is formed. The mol­ecules are linked by intra­molecular O_water—H⋯O and inter­molecular N—H⋯O and O_water—H⋯O hydrogen bonds, forming a three‐dimensional network.     

Tetra­kis(μ2‐1,8‐naphthyridine)‐1:2κ4N:N′;3:4κ4N:N′‐bis­(μ2‐salicylato)‐1:4κ2O:O′;2:3κ2O:O′‐tetrakis­(salicylic acid)‐1κO,2κO,3κO,4κO‐tetra­silver(I)(4 Ag—Ag)

The title complex, [Ag₄(C₇H₅O₃)₂(C₈H₆N₂)₄(C₇H₆O₃)₄], lies about an inversion centre and has a unique tetra­nuclear structure consisting of four Ag^I atoms bridged by four N atoms from two 1,8‐naphthyridine (napy) ligands to form an N:N′‐bridge and four O atoms from two salicylate (SA) ligands to form an O:O′‐bridge. The Ag atoms have distorted octa­hedral coordination geometry. The centrosymmetric Ag₄ ring has Ag—Ag separations of 2.772 (2) and 3.127 (2) Å, and Ag—Ag—Ag angles of 107.70 (4) and 72.30 (4)°. All SA hydroxy groups take part in intra­molecular O—H⋯O hydrogen bonding. In the crystal packing, the napy rings are oriented parallel and overlap one another. These π–π inter­actions, together with weak inter­molecular C—H⋯O contacts, stabilize the crystal structure.     

Bis(2‐amino‐3,5‐dibromo‐4,6‐dimethyl­pyridinium) hexa­bromido­stannate(IV)

In the title compound, (C₇H₉Br₂N₂)₂[SnBr₆], the cations and centrosymmetric anions are stacked in alternating layers that show no significant inter­molecular inter­actions within each stack. Extensive cation⋯[SnBr₆]²⁻ inter­actions are found, represented by short Br⋯Br inter­actions, along with different Br⋯HN (pyridine and amine) and weaker Br⋯HCH₂ hydrogen‐bonding motifs.     

Aqua­(di‐2‐pyridylamine)oxalato­copper(II) monohydrate

In the structure of the title complex, [Cu(C₂O₄)(C₁₀H₉N₃)(H₂O)]·H₂O, the Cu^II atom displays a square‐pyramidal geometry, being coordinated by two N atoms from the di‐2‐pyridylamine ligand, two O atoms from the oxalate group and one O atom of a water mol­ecule. The complex mol­ecules are linked to form a three‐dimensional supra­molecular array by hydrogen‐bonding inter­actions between coordinated/uncoordinated water mol­ecules and the uncoordinated oxalate O atoms of neighboring mol­ecules.     

A triclinic polymorph of 1,3‐thia­zolidine‐2‐thione (2‐mercaptothia­zoline)

A planar conformation of 1,3‐thia­zolidine‐2‐thione (TZDTH), C₃H₅NS₂, was crystallized for the first time. The new triclinic polymorph (P) obtained was compared in terms of its intra‐ and inter­molecular geometry with three previous reports of a monoclinic polymorph (P2₁/n). The packing is based on centrosymmetric dimers of TZDTH, linked by N—H⋯S hydrogen bonds.     

3,3a‐Dihydrocyclo­penta­[b]­chromen‐1(2H)‐ones from the reaction of salicylaldehyde and 2‐cyclo­penten‐1‐one

The two title chromene compounds, 3,3a‐dihydrocyclo­penta­[b]chromen‐1(2H)‐one, C₁₆H₁₂O₂, (I), and 2‐(2‐hydroxy­benzyl­idene)‐3,3a‐dihydrocyclo­penta­[b]chromen‐1(2H)‐one, C₁₉H₁₄O₃, (II), have been determined in the monoclinic space group P2₁/n. Compound (I) is mainly stabilized by C—H⋯π inter­actions. Compound (II) is linked into infinite one‐dimensional chains with a C(3) motif via inter­molecular O—H⋯O hydrogen bonds. The inter­molecular C—H⋯π and π–­π inter­actions also play key roles in stabilizing the crystal packing. Two intra­molecular C—H⋯O hydrogen bonds with S(5) motifs were detected in (II).     

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.     

catena‐Poly[[aqua­(2,2′‐bipyridine‐κ2N,N′)cadmium(II)]‐μ‐4‐carboxyl­atophenoxy­acetato‐κ3O:O4,O4′]

In the title compound, [Cd(C₉H₆O₅)(C₁₀H₈N₂)(H₂O)]_n, the Cd^II atom is coordinated in a distorted octa­hedral fashion by two carboxyl­ate groups (one in a monodentate and one in a bidentate fashion) from two 4‐carboxyl­ato­phenoxy­acetate anions, two N atoms from a 2,2′‐bipyridine ligand and one aqua ligand. The structure is a helix with a long pitch of 16.441 (5) Å. A three‐dimensional supra­molecular network is further constructed through π–π stacking and hydrogen‐bonding inter­actions between the helices.