(P,M)‐1,2,3,9,10,11‐Hexa­methoxy‐5,7‐di­hydro­dibenz­[c,e]­oxepine and (P,M)‐1,11‐di­methyl‐5,5,7,7‐tetra­phenyl‐5,7‐di­hydro­dibenz­[c,e]­oxepine

The title compounds, C₂₀H₂₄O₇ and C₄₀H₃₂O, respectively, are racemic oxepines, the mol­ecules of which contain a chiral axis. Both mol­ecules possess crystallographic C₂ symmetry and the seven‐membered ring adopts a twisted‐boat confor­mation.     

1‐Chloro‐3,6‐di­methoxy‐2,5‐di­methyl­benzene and 1‐chloro‐3,6‐di­methoxy‐2,4‐di­methyl­benzene

The title compounds, 1‐chloro‐3,6‐di­methoxy‐2,5‐di­methyl­benzene, (IIIa), and 1‐­chloro‐3,6‐di­methoxy‐2,4‐di­methyl­benzene, (IIIb), both C₁₀H₁₃ClO₂, were obtained from 2,5‐ and 2,6‐di­methyl‐1,4‐benzo­quinone, respectively, and are intermediates in the synthesis of ammonium quinone derivatives. The isomers have different substituents around the methoxy groups and crystallize in different space groups. In both mol­ecules, the methoxy groups each have different orientations with respect to the benzene ring. In both cases, one methoxy group lies in the plane of the ring and can participate in conjugation with the aromatic system, while the second is almost perpendicular to the plane of the aromatic ring. The C—O—C bond angles around these substituents are also different: 117.5 (4) and 118.2 (3)° in (IIIa) and (IIIb), respectively, when the methoxy groups lie in the plane of the ring, and 114.7 (3) and 113.6 (3)° in (IIIa) and (IIIb), respectively, when they are out of the plane of the ring.     

Benzo­[i]­naphtho­[c,d]­bi­cyclo­[5.4.1]dodecan‐12‐one

In the title compound, penta­cyclo­[11.8.1.1^3,11.0^7,23.0^15,20]­tricosa‐3,5,7,9,11(23),15,17,19‐octaen‐22‐one, C₂₃H₂₀O, the bi­cyclo­[5.4.1]­dodecan‐12‐one moiety takes a rigid conformation in which the seven‐ and eight‐membered rings take chair and boat–boat forms, respectively. The mol­ecule has a non‐crystallographic mirror symmetry perpendicular to the benzene and naphthalene planes.     

1‐[2‐(1‐Hydroxy­cyclo­hexyl)‐2‐(4‐methoxy­phenyl)­ethyl]­di­methyl­ammon­ium chloride (venlafaxine hydro­chloride)

The crystal structure of racemic Venlafaxine hydro­chloride, C₁₇H₂₈NO₂⁺·Cl^?, consists of two types of parallel chains formed by translated Venlafaxine⁺ cations, hydrogen bonded by Cl^? anions, and characterized by the opposite chirality of their constituent mol­ecules. These chains organize in two different types of broad layers of opposite handedness, related by a glide plane.     

Synthesis and molecular structure of novel 4‐aryloctahydropyrido‐[1,2‐c]pyrimidine derivatives

A series of new 4‐aryloctahydropyrido[1,2‐c]pyrimidine‐1,3‐diones 6a,b,d‐h and j were synthesized by intramolecular cyclization of α‐aryl‐α‐(1‐ethoxycarbonyl‐2‐piperidyl)‐acetamide derivatives 5a,b,d‐h and j . The structures of compounds were determined by ¹H and ¹³C nmr spectroscopy. Nmr and X‐ray diffraction data indicate that the configuration at the C4, C4a stereocenters constitute RR and SS pair.     

5,6‐Di­phenyl­[1,3]­di­thiolo­[4,5‐b]di­thiine‐2‐thione

In the title compound, C₁₇H₁₀S₅, the dithiine ring adopts a boat conformation while the di­thiole ring has an envelope conformation. The phenyl groups are planar and make dihedral angles of 40.7 (2) and 59.8 (2)° with the best plane of the thiine ring. The shortest intermolecular S?S contact is 3.305 (2) Å.     

2‐[3‐Furyl­(hydroxy)­methyl]‐2,3‐di­methyl­cyclo­hexanone

In the mol­ecule of the title compound, C₁₃H₁₈O₃, there is a syn relationship between the two vicinal methyl groups. The six‐membered ring adopts a chair conformation, with one equatorial and two axial groups, and the furyl group is almost parallel to the ketone group. Intermolecular hydrogen bonds [O—H?O=C 2.814 (3) Å] form chains along [100].     

Hydrogen‐bonding and C—H⋯π interactions in 7‐hydroxy‐3‐methoxy‐4‐methyl‐5,6,7,8‐tetrahydro­pyrido­[1,2‐c]pyrimidin‐1(9H)‐one

In the title compound, C₁₀H₁₄N₂O₃, a pyrimidine ring is fused with a piperidine ring. The pyrimidine ring is planar, whereas the piperidine ring adopts a half‐chair conformation. The molecules of the title compound are connected via O—H⋯O intermolecular hydrogen bonds into infinite zigzag chains. The pyrimidine ring is involved in three C—H⋯π interactions, which link the hydrogen‐bonded chains into a three‐dimensional framework.     

Bis­[N,N‐bis(2‐hydroxy­ethyl)­di­thio­carbamato]­di­methyl­tin(IV)

The title compound, [Sn(CH₃)₂(C₅H₁₀NO₂S₂)₂], has crystallographic mirror symmetry (C—Sn—C on mirror plane) and the coordination polyhedron around the Sn atom is a tetrahedron [C—Sn—C 139.3 (2)° and S—Sn—S 82.3 (1)°] distorted towards a skew‐trapezoidal bipyramid owing to an intramolecular Sn?S contact [3.0427 (6) Å]. The mol­ecules are linked into a linear chain by intermolecular O—H?O hydrogen bonds [O?O 2.646 (3) Å].     

Bis­[4‐(di­methyl­amino)­pyridinium] hexa­chloro­stannate(IV)

In the title compound, 4‐(di­methyl­amino)­pyridine is proton­ated on the pyridine N atom. The N(CH₃)₂ moiety is twisted 4.4 (2)° from the pyridine‐ring plane. The octahedral [SnCl₆]^2? anion is hydrogen bonded via trans‐Cl atoms to pyridinium N atoms from two cations forming (C₇H₁₁N₂)₂[SnCl₆] structural units.     

Bis­[2‐(di­phenyl­phosphinoyl)­benzene] di­sulfide

The title compound, [2‐Ph₂P(O)C₆H₄S]₂ or C₃₆H₂₈O₂P₂S₂, obtained by electrochemical oxidation of 2‐(di­phenyl­phosphino)­benzene­thiol, has twofold crystallographic symmetry. Principal dimensions include S—S 2.0212 (15) Å, S—C 1.786 (3) Å and C—S—S—C 81.34 (14)°.     

2‐tert‐Butyl­oxy­methyl‐6‐cyano‐2,3‐di­hydro‐5H‐oxazolo­[3,2‐a]­pyrimidin‐5‐one

The condensation reaction of 2‐amino‐5‐tert‐butyl­oxy­methyl‐2‐oxazoline with ethyl cyano­(ethoxy­methyl­ene)­acetate led to the title cycloadduct. The structure indicates a delocalization in the pyrimidine ring.     

2‐[Benzoyl­(hydroxy­imino)­methyl­amino]­benzoic acid

The structure of the title compound, C₁₅H₁₂N₂O₄, consists of a polymeric arrangement, around inversion centres, of mol­ecules linked through O—H⋯N and O—H⋯O hydrogen bonds; there are also intramolecular hydrogen bonds. All these hydrogen‐bond interactions result in the formation of infinite chains parallel to the [010] direction. The oxime group has an E conformation.     

(E,E)‐2,5‐Di­methoxy‐1,4‐bis­[2‐(3,4,5‐tri­methoxy­phenyl)­ethenyl]­benzene

In the title compound, C₃₀H₃₄O₈, molecular symmetry is coincident with crystallographic inversion symmetry. A three‐dimensional network is generated containing both C—H·π and C—H·n(O) interactions. A comparison of the geometry of this mol­ecule and the structure of a number of 2,4,6‐tri­methoxy‐substituted analogues is provided.     

Supramolecular structures of 2‐cyano‐3‐di­methyl­amino‐N‐(4‐methyl­phenyl)­acryl­amide and 2‐cyano‐3‐di­methyl­amino‐N‐(2‐methoxy­phenyl)­acryl­amide

In the title compounds, C₁₃H₁₅N₃O, (I), and C₁₃H₁₅N₃O₂, (II), the dihedral angles between the planes of the phenyl ring and the amide group are 4.1 (1) and 20.7 (1)°, respectively. The mol­ecules adopt a fully extended conformation, aided by intramolecular interactions. The molecular structures of (I) and (II) display different crystal packing and hydrogen‐bonding networks.     

8‐Chloro‐6‐phenyl‐4H‐[1,2,4]­triazolo­[4,3‐a][1,5]­benzodiazepin‐5(6H)‐one

The title compound, C₁₆H₁₁ClN₄O, is an anticonvulsant agent. In the crystal, a particularly short C—H?N intermolecular hydrogen bond is noted [H?N 2.22 (2) Å]. The diazepine ring has a boat conformation.     

1‐(2‐Hydroxy‐4,6‐di­methyl­phenyl)­ethanone

In the crystal of the title compound, C₁₀H₁₂O₂, there are two symmetry‐independent mol­ecules, which are essentially superimposable. Each mol­ecule exhibits an intramolecular O—H?O hydrogen bond, with O?O separations of 2.483 (4) and 2.468 (4) Å.     

1‐[(4‐Chloro­benzoyl)­methyl]‐4‐(N,N‐di­methyl­amino)­pyridinium bromide sesquihydrate and 1‐[(4‐bromo­benzoyl)­methyl]‐4‐(N,N‐di­methyl­amino)­pyridinium bromide sesquihydrate

The title compounds, C₁₅H₁₆ClN₂O⁺·Br⁻·1.5H₂O and C₁₅H₁₆BrN₂O⁺·Br⁻·1.5H₂O, are isomorphous. The benzene ring is oriented nearly normal to the pyridine ring in both compounds. The molecular packing is mainly influenced by intermolecular O—H⋯O and O—H⋯Br interactions, as well as weak intramolecular C—H⋯O interactions. The H₂OBr⁻ units form an extended water–bromide chain, with a bridging water mol­ecule on a twofold axis.     

4,6‐Bis­(methyl­sulfanyl)‐1‐(4‐phenoxy­butyl)‐1H‐pyrazolo­[3,4‐d]­pyrimidine

The molecular structure of the title compound, C₁₇H₂₀N₄OS₂, does not show any intramolecular aromatic π–π interactions, but the crystal packing reveals the presence of intermolecular C—H...O and C—H...π interactions. The C—H...O interactions generate chains of mol­ecules that are linked into sheets by C—H...π interactions about inversion centres.     

trans‐[1,3‐Bis(2,4‐di­methyl­phenyl)­imidazolidin‐2‐yl­idene]­di­chloro­(tri­phenyl­phosphine‐κP)­palladium(II)

The title complex, [PdCl₂(C₁₉H₂₂N₂)(C₁₈H₁₅P)], shows slightly distorted square‐planar coordination of the palladium(II) metal center. The Pd—C bond distance between the N‐heterocyclic ligand and the metal atom is 2.008 (3) Å. The dihedral angle between the two di­methyl­phenyl ring planes is 33.17 (13)°.