N‐(4‐Bi­phenyl­yl)­urea

In the crystal structure of the title compound, C₁₃H₁₂N₂O, N—H(anti)?O hydrogen bonds produce the so‐called urea α‐network and the N—H(syn) donor forms an unconventional N—H?π hydrogen bond.     

4‐[N,N‐Bis(2‐cyano­ethyl)­amino]­pyridine

The title compound, 3,3′‐(4‐pyridyl­imino)­di­propane­nitrile, C₁₁H₁₂N₄, has a twofold axis and consists of a pyridine ring head and two cyano­ethyl tails, the three groups being linked by an N atom. The planar geometry around the amino N atom suggests conjugation with the π‐system of the pyridine ring. The mol­ecules are stacked in a layer structure via relatively weak to very weak intermolecular C—H⃛π and C—H⃛N hydrogen‐bond interactions.     

4,6‐Di­chloro‐2‐(methyl­thio)­pyrimidine

The structure of the title compound, C₃₀H₂₄Cl₁₂N₁₂S₆, (I), comprises six symmetry unique mol­ecules that vary only slightly in their N—C—S—C torsion angle. All the mol­ecules are planar to within less than 3.1°.     

2‐Amino‐6‐chloro‐4‐(1‐phenyl­ethyl­amino)­pyrimidine

The structure of the title compound, C₁₂H₁₃ClN₄, (I), comprises a racemic mixture of chiral mol­ecules associated by N—H?N hydrogen‐bonding interactions. The dihedral angle between the two rings is 77.90 (6)°.     

(2‐Amino­ethoxy)­bis(2‐thienyl)­boron

In the five‐membered ring in the title compound, (2‐amino­ethoxy)­bis(2‐thienyl)­boron, C₁₀H₁₂BNOS_2, the B atom is four‐coordinate with dimensions N—B 1.654 (3), O—B 1.479 (3), and C—B 1.606 (3) and 1.609 (3) Å. An intermolecular hydrogen bond between an amino H atom and the ethoxy O atom links the mol­ecules into infinite chains along the a axis. Only one of the two amino H atoms is involved in hydrogen bonding because there is only the one acceptor atom, the ethoxy O atom, and the molecular geometry precludes formation of a second hydrogen bond by the second amino H atom.     

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.     

(Dicyclohexyldithiophosphinato‐S,S′)[2‐(2‐pyridyl‐N)­phenyl]­mercury(II)

The crystal structure of the title compound, [Hg(C₁₁H₈N)(C₁₂H₂₂PS₂)], consists of mol­ecules in which the Hg atom is coordinated strongly to the C atom in position 2 of the phenyl group and to one of the di­thio­phosphinate S atoms, and at longer distances to the pyridine N atom and the other S atom. The C—Hg—S fragment involving the S atom more strongly bound to Hg is almost linear [C—Hg—S = 178.9 (3)°].     

Chains of fused rings in the hydrogen‐bonded structure of meso‐­6,13‐di­amino‐6,13‐di­methyl‐1,4,8,11‐tetra­aza­cyclo­tetra­decane–2,2′‐biphenol (1/2)

The title compound is a salt, [C₁₂H₃₂N₆]²⁺·2[HOC₆H₄C₆H₄O]^?. The centrosymmetric cation contains two intramolecular N—H?N hydrogen bonds with an N?N distance of 2.8290 (13) Å, and the pendent amino groups are in axial sites; the anion contains an intramolecular O—H?O hydrogen bond with an O?O distance of 2.4656 (11) Å. The ions are linked into continuous chains by means of four types of N—H?O hydrogen bonds with N?O distances ranging from 2.7238 (12) Å to 3.3091 (13) Å, associated with N—H?O angles in the range 148–160°.     

[μ‐N,N′‐Bis(2‐amino­ethyl)­oxamidato(2–)]­bis­[(4,5‐di­aza­fluoren‐9‐one)­perchloratocopper(II)] 4,5‐di­aza­fluoren‐9‐one disolvate

The title compound, [Cu₂(C₆H₁₂N₄O₂)(ClO₄)₂(C₁₁H₆N₂O)₂]·2C₁₁H₆N₂O, contains a dinuclear copper(II) complex which lies about a twofold axis at the mid‐point of the C—C bond of the ox­amide ligand that bridges the two Cu^II atoms. The Cu·Cu distance is 5.215 (2) Å and the Cu atoms have distorted octahedral coordination geometry. Intramolecular N—H·O and N—H·N hydrogen bonds and intermolecular C—H·O hydrogen bonds, together with π–π stacking interactions, dominate throughout the crystal structure.     

Poly­sulfonyl­amines. CLXXI. [Di­(methane­sulfonyl)­amido‐κN]­bis(2‐picoline‐κN)copper(I)

The title compound, [Cu(C₂H₆NO₄S₂)(C₆H₇N)₂], consists of monomeric mol­ecules in which the Cu atom displays planar but irregular coordination by three N‐atom donors; Cu—N = 2.1054 (12) (amide N), 1.9514 (12) and 1.9589 (12) Å, and N—Cu—N = 141.24 (5), 111.54 (5) and 107.20 (5)°. Intramolecular Cu⋯O contacts are observed. The packing involves (interconnected) layer formation via C—H⋯O interactions in two directions, three hydrogen bonds combining to form layers parallel to (101) and five to form layers parallel to (10).     

Di­cyano{[(1S)‐(1‐phenyl­ethyl)­aziridin‐2‐yl]­methano­lato‐κ2N,O}boron

In the title compound, C₁₃H₁₄BN₃O, the aziridine ring is an almost equilateral triangle, the C—C distance being slightly shorter than the C—N distances, probably because of the dative B—N bond. The five‐membered ring, composed of two C atoms and N, B and O atoms, is fused with the aziridine ring to form a six‐membered ring with a chair conformation.     

3,6‐Bis­(4‐hydroxy­benzyl)­piperazine‐2,5‐dione

In the title compound, C₁₈H₁₆N₂O₄, the piperidine ring adopts a chair conformation, lying on an inversion centre. The 4‐hydroxy­benzyl groups are in quasi‐axial positions. A two‐dimensional network is formed through N—H?O and O—H?O intermolecular hydrogen bonds and C—H?O interactions.     

N‐(4‐Methoxy­benzyl­idene)‐N′‐(2‐pyridyl)­hydrazine

Molecules of the title compound (alternative name p‐methoxybenzaldehyde 2‐pyridyl­hydrazone), C₁₃H₁₃N₃O, adopt an E configuration about the azomethine C=N double bond. Molecules are almost planar, the dihedral angle between the pyridine and methoxy­phenyl rings being only 6.19 (12)°. Pairwise N—H⃛N hydrogen bonds [R(8) in graph‐set notation] link centrosymmetrically related mol­ecules into discrete pairs.     

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.     

1,3‐Bis(4‐nitro­phenyl)­triazene

The structure of the title compound, C₁₂H₉N₅O₄, reveals an almost planar mol­ecule (r.m.s. deviation = 0.061 Å), in which the interplanar angle between the phenyl rings is 5.7 (1)° and the largest interplanar angle is that between the phenyl ring and the nitro group of one of the 4‐nitro­phenyl substituents [8.8 (3)°]. The observed mol­ecular conformation suggests a delocalization of π‐electrons extended over the diazo­amine group and the terminal aryl substituents. Intermolecular N—H⃛O interactions between the twofold screw‐related mol­ecules give rise to helical chains along the [010] direction. Intermolecular C—H⃛O interactions then generate sheets of mol­ecules in the (10) plane, and these sheets are held together by N⃛C and O⃛O π–π interactions.     

Ethyl (2‐pyridyl­methyl)­phospho­nate

Molecules of the title compound, C₈H₁₂NO₃P, exist as zwitterions. The positive charge formally located on the N atom is spread over the pyridyl ring. A partial delocalization of negative charge within the O—P—O system is observed. The conformational features and hydrogen‐bonding network of the title compound are compared with the structure of (2‐pyridyl­methyl)­phosphonic acid.     

An unexpected chelate conformation in trans‐[(R)‐N,N′‐bis(α‐phenyl­salicyl­idene)­propane‐1,2‐diaminato(2–)]­bis(1‐methyl‐1H‐imidazole‐κN3)­cobalt(III) perchlorate

The title compound, [Co(C₂₉H₂₄N₂O₂)(C₄H₆N₂)₂]ClO₄, contains an optically active tetradentate Schiff base ligand in an equatorial plane and two 1‐methyl­imidazole ligands at apical positions. The central N—C—C—N chelate ring of the Schiff base ligand has an envelope structure with a λ conformation, which is different from the solution structure predicted from circular dichroism and ¹H NMR spectra.     

Bis[bis­(2‐pyridylcarbon­yl)­aminato]­iron(III) perchlorate acetonitrile disolvate

The title compound, [Fe(C₁₂H₈N₃O₂)₂]ClO₄·2C₂H₃N, contains Fe^III in a distorted octa­hedral coordination environment, with the Fe—N(pyridine) bonds significantly longer than the Fe—N(amine) bonds. The crystal packing involves a bifurcated C—H⋯(O,O) contact that is also found in all other [M(C₁₂H₈N₃O₂)₂] complexes reported previously.     

5‐Chloro‐N‐(2‐hydroxy‐5‐methyl­phenyl)­salicyl­ald­imine

The title compound, N‐(5‐chloro‐2‐oxido­benzyl­idene)‐2‐hydroxy‐5‐methyl­anilinium, C₁₄H₁₂ClNO₂, is a tridentate Schiff base with almost planar molecules. Each mol­ecule contains a strong intramolecular N—H?O hydrogen bond [2.576 (2) Å]. There is also an intermolecular O—H?O hydrogen bond [2.695 (2) Å] linking neighbouring mol­ecules into infinite chains along the [101] direction.     

3‐(4‐Acetyl­phenyl)‐1‐(4‐nitro­phenyl)­triazene

The crystal structure of the title compound, C₁₄H₁₂N₄O₃, shows that the stereochemistry about the N=N double bond of the N=N—N(H) moiety is trans. The whole mol­ecule is almost planar (r.m.s. deviation = 0.0654 Å), the interplanar angle between the phenyl rings being 0.7 (1)° and the largest interplanar angle being that between the phenyl ring and the nitro group of the 4‐nitro­phenyl substituent [11.5 (2)°]. Intermolecular N—H⋯O interactions between mol­ecules related by translation give rise to chains along the [110] and [10] directions, and these chains are held together by N⋯O π–π interactions. An unequal distribution of the double‐bond character among the N atoms suggests a delocalization of π electrons over the diazo­amine group and the adjacent aryl substituents.