(R)‐4‐(4‐Aminophenyl)‐2,2,4‐trimethylchroman and (S)‐4‐(4‐aminophenyl)‐2,2,4‐trimethylthiachroman

The title compounds, C₁₈H₂₁NO and C₁₈H₂₁NS, in their enantiomerically pure forms are isostructural with the enantiomerically pure 4‐(4‐hydroxyphenyl)‐2,2,4‐trimethylchroman and 4‐(2,4‐dihydroxyphenyl)‐2,2,4‐trimethylchroman analogues and form extended linear chains via N—H...O or N—H...S hydrogen bonding along the [100] direction. The absolute configuration for both compounds was determined by anomalous dispersion methods with reference to both the Flack parameter and, for the light‐atom compound, Bayesian statistics on Bijvoet differences.     

4‐Amino‐3‐methyl‐6‐phenyl‐1,2,4‐triazin‐5(4H)‐one (metamitron) and 4‐amino‐6‐methyl‐3‐phenyl‐1,2,4‐triazin‐5(4H)‐one (isometamitron)

The title structures, both C₁₀H₁₀N₄O, are substitutional isomers. The N—N bond lengths are longer and the C=N bond lengths are shorter by ca 0.025 Å than the respective average values in the C=N—N=C group of asymmetric triazines; the assessed respective bond orders are 1.3 and 1.7. There are N—H⋯O and N—H⋯N hydrogen bonds in both structures, with 4‐­amino‐3‐methyl‐6‐phenyl‐1,2,4‐triazin‐5(4H)‐one containing a rare bifurcated N—H⋯N,N hydrogen bond. The structures differ in their mol­ecular stacking and the hydrogen‐bonding patterns.     

2,9‐Bis(3‐nitrophenyl)‐1‐azaadamantan‐4‐one

The title compound, 2,9‐bis(3‐nitro­phenyl)‐1‐aza­tri­cyclo[3.3.1.1^3,7]­decan‐4‐one, C₂₁H₁₉N₃O₅, has a tricyclic structure. The torsion angles may be used to describe the relationship of the carbonyl group to the adjacent faces, whereby it is seen that the angles on the face of the aryl­piperidinone side [122.0 (3) and ?122.0 (3)°] are greater than those on the cyclo­hexanone side [?119.8 (4) and 119.9 (4)°]. Although these differences may explain a facial selectivity during nucleophilic addition to the carbonyl group, the presence of the aryl rings is probably also important.     

catena‐Poly[copper(II)‐di‐μ‐acetylacetonato‐copper(II)‐bis(μ‐4‐hydroxy‐3‐methoxybenzaldehyde picoloylhydrazonato)] and (acetylacetonato)(4‐methoxybenzaldehyde picoloylhydrazonato)copper(II)

In the two title copper(II) complexes, [CuL(C₅H₇O₂)]_n, (I), and [CuL′(C₅H₇O₂)], (II), respectively, where HL is 4‐hydroxy‐3‐methoxybenzaldehyde picoloylhydrazone, C₁₄H₁₂N₃O₃, and HL′ is 4‐methoxybenzaldehyde picoloylhydrazone, C₁₄H₁₂N₃O₂, the Cu^II ions display a highly Jahn–Teller‐distorted octahedral and a square‐planar coordination geometry, respectively. In complex (I), two neighbouring Cu^II atoms are bridged by L⁻ and acetylacetonate, alternately, giving rise to a one‐dimensional chain of CuN₂O₄ octahedra interconnected by these two ligands along the a axis. In addition, the hydroxy H atom of the vanillin group connects to the carboxyl O atom of the adjacent chain via an O—H...O hydrogen bond, giving rise to a three‐dimensional supramolecular assembly. Complex (II) displays a discrete structure.     

2,2‐Dichloro‐1,3‐bis(trimethylsilyl)‐1,3‐diaza‐2‐silacyclopentane

In the title compound, C₈H₂₂Cl₂N₂Si₃, the central Si atom is tetrahedrally coordinated by two Cl and two N atoms in a molecule that has crystallographically imposed C₂ symmetry. Comparison is made with the isomorphous structure having titanium instead of silicon at the central position in the diazacyclopentane ring [Tinkler, Deeth, Duncalf & McCamley (1996). Chem. Commun. pp. 2623–2624].     

4,4′‐Bis(2,2,2‐trifluoroethoxymethyl)‐2,2′‐bipyridine

As part of a homologous series of novel polyfluorinated bipyridyl (bpy) ligands, the title compound, C₁₆H₁₄F₆N₂O₂, contains the smallest fluorinated group, viz. CF₃. The molecule resides on a crystallographic inversion centre at the mid‐point of the pyridine C_ipso—C_ipso bond. Therefore, the bpy skeleton lies in an anti conformation to avoid repulsion between the two pyridyl N atoms. Weak intramolecular C—H...N and C—H...O interactions are observed, similar to those in related polyfluorinated bpy–metal complexes. A π–π interaction is observed between the bpy rings of adjacent molecules and this is probably a primary driving force in crystallization. Weak intermolecular C—H...N hydrogen bonding is present between one of the CF₃CH₂– methylene H atoms and a pyridyl N atom related by translation along the [010] direction, in addition to weak benzyl‐type C—H...F interactions to atoms of the terminal CF₃ group. It is of note that the O—CH₂CF₃ bond is almost perpendicular to the bpy plane.     

catena‐Poly[[[bis(μ‐4,5‐dihydrothiazole‐2‐thiolato)‐tetrahedro‐tetracopper(I)]‐di‐μ‐4,5‐dihydrothiazole‐2‐thiolato] dihydrate]

The title compound, {[Cu₄(C₃H₄NS₂)₄]·2H₂O}_n, was produced by diffusing a solution of 2‐mercapto­thia­zoline in tetra­hydro­furan into a solution of CuCl in CH₃CN at room temperature. The structure is characterized by self‐assembled one‐dimensional chains that are condensed from butterfly‐like [Cu(C₃H₄NS₂)]₄ tetrameric units via double S‐bridging at opposite ends. The Cu—Cu distances within the Cu₄ butterfly cluster are in the range 2.7103 (10)–2.9764 (10) Å, while the shortest Cu?Cu intercluster distance is 3.468 (1) Å, much longer than the sum of the van der Waals radii.     

[μ3‐cis‐N‐(2‐Aminoethyl)‐N′‐(2‐carboxylatophenyl)oxamidato(3−)]bis(2,2′‐diamino‐4,4′‐bi‐1,3‐thiazole)tetracopper(II) bis(2,4,6‐trinitrophenolate)

The title complex, [Cu₄(C₁₁H₁₀N₃O₄)₂(C₆H₆N₄S₂)₂](C₆H₂N₃O₇)₂, consists of a circular tetracopper(II) cation with an embedded inversion centre and two uncoordinated picrate (2,4,6‐trinitrophenolate) anions. The Cu^II cations at the inner sites of N‐(2‐aminoethyl)‐N′‐(2‐carboxylatophenyl)oxamidate(3−) (oxbe) have square‐planar environments and those at the outer sites are in square‐pyramidal geometries. The separations of pairs of Cu^II cations bridged by cis‐oxamide and carboxylate groups are 5.2217 (5) and 5.2871 (5) Å, respectively. The tetracopper(II) cations and picrate anions are connected by N—H...O hydrogen bonds into a two‐dimensional network parallel to the (010) plane, and these two‐dimensional networks are assembled by two types of π–π stacking interactions into a three‐dimensional supramolecular structure.     

catena‐Poly[tetra­kis(3‐phenyl­propyl­ammonium) [iodo­plumbate(II)‐tri‐μ‐iodo‐plumbate(II)‐tri‐μ‐iodo‐iodo­plumbate(II)‐di‐μ‐iodo]]

The title compound, {(C₉H₁₄N)₄[Pb₃I₁₀]}_n, crystallizes as an organic–inorganic hybrid. As such, the structure consists of a two‐dimensional inorganic layer of [Pb₃I₁₀]_n⁴ⁿ⁻ ions extending along [100]. The asymmetric unit contains two independent Pb atoms, viz. one in a general position and the other on an inversion centre. Each Pb atom is octa­hedrally coordinated by six iodide ions and exhibits both face‐ and corner‐sharing with adjacent atoms in the inorganic layer. These anionic layers alternate with 3‐phenyl­propyl­ammonium cations, which hydrogen bond to the iodides. Simple face‐to‐edge σ–π stacking inter­actions are observed between the aromatic rings that stabilize the overall three‐dimensional structure. This net structure has only been observed five times previously.     

4,5‐Bis(furoylsulfanyl)‐1,3‐dithiole‐2‐thione

The title compound, C₁₃H₆O₄S₅, possesses crystallographically imposed mirror symmetry, with the atoms of the C=S group lying on the mirror plane. It is an example of the general formula [RCO]₂(dmit), where R is a furan ring and dmit is 2‐thioxo‐1,3‐dithiole‐4,5‐dithiol­ate. The components exhibit some polarization of their mol­ecular–electronic structure. The dmit and furan moieties exhibit a high degree of conjugation, as the introduction of C=O connecting the conjugated furan (donor) and dmit (acceptor) rings forms a good conjugated system with high delocalization. A polar three‐dimensional framework is built from a combination of inter­molecular contacts, namely S⋯S inter­actions and C—H⋯O hydrogen bonding. The structural characteristics lead to good second‐order non‐linear optical properties.     

(Z)‐5‐[4‐(Dimethylamino)benzylidene]‐2‐(piperidin‐1‐yl)‐1,3‐thiazolidin‐4(5H)‐one

The molecules of the title compound, C₁₇H₂₁N₃OS, are characterized by a wide C—C—C angle at the methine C atom linking the aryl and thiazolidine rings, associated with a short repulsive intramolecular S...H contact between atoms in these two rings. A single piperidine–arene C—H...π hydrogen bond links pairs of molecules into centrosymmetric dimers.     

Total Synthesis of (-)-Kaerophyllin,(-)-Hinokinin and (±)-Isohinokinin

Kaerophyllin (1) ,hinokinin (2 )andtheiranalogue isohinokinin (3)belongtothedibenzylbutyrolactone lig nans .Kaerophyllin (1)wasisolatedfromtherootofspot tedcowparsley (ChaerophyllummaculatumWilld .) 1andhinokinin (2 )wasisolatedfromtheheartwoodofLiboce drusformosanaFlorin .2 AccordingtoMacRaeandTow ers ,3afivememberedlactoneringandamethylenedioxylgroupwereimportantstructuralcharacteristicswhichcon tributetotheactivityoflignansasantitumoragents .More over ,anunsaturateddoublebondbetweenC3—…     

Annulenoide Tetrathiafulvalene:, 5,16‐Bis(1,3‐benzodithiol‐2‐yliden)‐5,16‐dihydrotetraepoxy‐ und 5,16‐Bis(1,3‐benzodithiol‐2‐yliden)‐5,16‐dihydrotetraepithio[22]annulene(2.1.2.1)

Annulenoid Tetrathiafulvalenes: 5,16‐Bis(1,3‐benzodithiol‐2‐ylidene)‐5,16‐dihydrotetraepoxy‐ and 5,16‐Bis(1,3‐benzodithiol‐2‐ylidene)‐5,16‐dihydrotetraepithio[22]annulenes(2.1.2.1) The title compounds are among the first tetrathiafulvalenes with annulene spacers, here with tetraepoxy‐[22]annulene(2.1.2.1) (see 3a ), tetraepithio[22]annulene(2.1.2.1) (see 3b ), and diepithiodiepoxy[22]annulene(2.1.2.1) (see 23 ) units. The annulenoid tetrathiafulvalenes 3a and 3b are prepared by cyclizing McMurry coupling of the 5,5′‐(1,3‐benzodithiol‐2‐ylidenemethylene)bis[furan‐ or thiophene‐2‐carbaldehydes] ( 8a or 8b , resp.) or by Wittig reaction of (1,3‐benzodithiol‐2‐yl)tributylphosphonium tetrafluoroborate ( 13b ) with tetraepoxy[22]annulene(2.1.2.1)‐1,12‐dione 20 (formation of 3a ) or diepithiodiepoxy[22]annulene(2.1.2.1)‐1,12‐dione 22 (formation of 23 ). The annulenoide tetrathiafulvalene 3a is obtained as a mixture of the isomers (E,E)‐ and (Z,Z)‐ 3a . At 130°, (Z,Z)‐ 3a rearranges quantitatively into the (E,E)‐isomer. Isomer (E,E)‐ 3a is a dynamic molecule, where the (E)‐ethene‐1,2‐diyl bridges rotate around the adjacent σ‐bonds. The tetraepithioannulene derivative 3b as well as 23 only exist in the (Z,Z)‐configuration. The oxidation of (E,E/Z,Z)‐ 3a with Br₂ yields the annulene‐bridged tetrathiafulvalene dication (E,E)‐ 3a _Ox, while with 4,5‐dichloro‐3,6‐dioxocyclohexa‐1,4‐diene‐1,2‐dicarbonitrile (DDQ) obviously only the radical cation 3a _Sem is formed, which belongs to the class of cyanine‐like violenes. The annulenoide tetrathiafulvalenes 3b and 23 , which exist only in the (Z,Z)‐configuration, obviously for steric reasons, cannot be oxidized by DDQ. Electrochemical studies are in agreement with these results.     

Wasserstoffbrücken in 1,1‐Bis(2‐hydroxyethyl)‐3‐benzoylthioharnstoff und seinen Nickel(II)‐ und Kupfer(II)‐Chelat‐Komplexen

Hydrogen Bonds in 1,1‐Bis(2‐hydroxyethyl)‐3‐benzoylthiourea and its Nickel(II)‐ and Copper(II)‐Chelate Complexes The ligand 1,1‐bis(2‐hydroxyethyl)‐3‐benzoylthiourea HL, ( 1 ), yields with nickel(II) and copper(II) ions neutral complexes [NiL₂], ( 2 ), and [CuL₂], ( 3 ). By X‐ray structure analysis and IR spectroscopy different intramolecular hydrogen bonds (OH…O) and (OH…N) could be identified in both equally coordinated ligands of the [NiL₂] molecule. For comparison X‐ray and IR data were also estimated for 1 and 3 .     

2,2′‐Diselenobis(4,4‐diphenylcyclohexa‐2,5‐dienone)

The title compound, C₃₆H₂₆O₂Se₂, displays crystallographic twofold symmetry. The packing involves corrugated linear ribbons mediated through C—H?O and C—H?Se inter­actions. The ribbons are connected through C—H?π inter­actions.     

4‐Phenyl‐3,5‐bis(2‐pyridyl)‐4H‐1,2,4‐triazole

In the title compound, C₁₈H₁₃N₅, the two pyridyl rings form dihedral angles of 32.7 (2) and 30.1 (2)° with the triazole ring. The most favoured orientation of the pyridyl rings is that with their N atoms on opposite sides of the triazole ring directed towards the phenyl ring. π–π‐Stacking interactions involving pyridyl rings are observed along the a axis at a perpendicular distance of 3.670 (3) Å. This arrangement is further stabilized by weak intermolecular C—H?N hydrogen bonds.     

[7,13‐Bis(2‐aminobenzyl)‐1,4,10‐trioxa‐7,13‐diazacyclopentadecane]diisothiocyanatobarium(II)

The X‐ray crystal structure of the title complex, [Ba(NCS)₂(C₂₄H₃₆N₄O₃)], indicates that the Ba^II cation is nine‐coordinate in the solid state, being fully encapsulated by the organic receptor ligand. The receptor adopts a syn arrangement, with both pendant arms oriented on the same side of the crown moiety. The distance between the two amine N atoms is 3.911 (12) Å, while the pivotal N atoms are 5.322 (10) Å apart.     

(E)‐N′‐(4‐Chlorobenzylidene)‐, (E)‐N′‐(4‐bromobenzylidene)‐ and (E)‐N′‐[4‐(diethylamino)benzylidene]‐ derivatives of 4‐hydroxybenzohydrazide

The 4‐chloro‐ [C₁₄H₁₁ClN₂O₂, (I)], 4‐bromo‐ [C₁₄H₁₀BrN₂O₂, (II)] and 4‐diethylamino‐ [C₁₈H₂₁N₃O₂, (III)] derivatives of benzylidene‐4‐hydroxybenzohydrazide, all crystallize in the same space group (P2₁/c), (I) and (II) also being isomorphous. In all three compounds, the conformation about the C=N bond is E. The molecules of (I) and (II) are relatively planar, with dihedral angles between the two benzene rings of 5.75 (12) and 9.81 (17)°, respectively. In (III), however, the same angle is 77.27 (9)°. In the crystal structures of (I) and (II), two‐dimensional slab‐like networks extending in the a and c directions are formed via N—H...O and O—H...O hydrogen bonds. The molecules stack head‐to‐tail viaπ–π interactions involving the aromatic rings [centroid–centroid distance = 3.7622 (14) Å in (I) and 3.8021 (19) Å in (II)]. In (III), undulating two‐dimensional networks extending in the b and c directions are formed via N—H...O and O—H...O hydrogen bonds. The molecules stack head‐to‐head viaπ–π interactions involving inversion‐related benzene rings [centroid–centroid distances = 3.6977 (12) and 3.8368 (11) Å].