The 1:1 adduct of hexa­methyl­ene­tetramine (HMT) with racemic trans‐1,2‐cyclo­hexane­di­carboxylic acid (CDA)

Hexa­methyl­ene­tetramine and rac‐trans‐1,2‐cyclo­hexane­di­carboxylic acid crystallize in a 1:1 ratio as a neutral molecular adduct, C₆H₁₂N₄·C₈H₁₂O₄. Two di­carboxylic acid mol­ecules and two tetr­amine mol­ecules form a hydrogen‐bonded ring, in the shape of a rhombus, which lies on a crystallographic twofold axis bisecting the two diacid mol­ecules. The O—H⋯N hydrogen bonds have lengths 2.6808 (19) and 2.6518 (19) Å, and, in each ring, both acid mol­ecules have the same handedness.     

Dimorphism in 3′‐amino­cyclo­hexane­spiro‐5′‐hydantoin

The title compound [systematic name: 1′‐amino­cyclo­hexane­spiro‐4′‐imidazole‐2′,5′(3′H,4′H)‐dione], C₈H₁₃N₃O₂, has been synthesized and was found to crystallize in two different structures, both monoclinic and both with the same P2₁/c space group. In the first structure, there are two mol­ecules in the asymmetric unit, one of which uses all of its hydrogen‐bond donors and acceptors and forms undulating layers, while the other forms chains propagating perpendicular to the layers. In the second structure, there is only one independent mol­ecule and the packing is based on a chain structure mediated by hydrogen bonding between the hydantoin moieties and further grouped into hydro­philic layers separated by layers of the hydro­phobic cyclo­hex­yl groups.     

2,2′‐(1,2‐Ethanediyldithio)bis(1,3‐benzothiazole)

In the title compound, C₁₆H₁₂N₂S₄, which is the result of the S‐alkyl­ation reaction of 2‐mercapto­benzo­thia­zole with ethyl­ene dibromide, the planes of the two benzo­thia­zole moieties form a dihedral angle of 3.84 (14)°. The bridging chain moiety, –SCH₂CH₂S–, adopts an antiperiplanar conformation. There are intermolecular S⃛S non‐bonded contacts of 3.6471 (9) Å, which stabilize the crystal packing.     

catena‐Poly­[[trans‐bis­(ethane‐1,2‐di­amine‐κ2N,N′)copper(II)]‐μ‐di­thion­ato‐κ2O:O′] and trans‐di­aqua­bis­(propane‐1,3‐di­amine‐κ2N,N′)copper(II) di­thionate

In title an­hydro­us catena‐poly­[[trans‐bis­(ethane‐1,2‐di­amine‐κ²N,N′)copper(II)]‐μ‐di­thionato‐κ²O:O′], [Cu(S₂O₆)(C₂H₈N₂)₂]_n or [{H₂N(CH₂)₂NH₂}₂Cu(O·O₂SSO₂·O)]_∞, successive Cu atoms are bridged by a single doubly charged di­thionate group, forming a one‐dimensional polymer with inversion centres at the metal atoms and the mid‐point of the S—S bond [Cu—O = 2.5744 (15) Å]. In title (hydrated) trans‐di­aqua­bis­(propane‐1,3‐di­amine‐κ²N,N′)copper(II) di­thionate, [Cu(C₃H₁₀N₂)₂(H₂O)₂](S₂O₆) or [{H₂N(CH₂)₃NH₂}₂Cu(OH₂)₂](S₂O₆), both ions have imposed 2/m symmetry. The `axial' anion components are displaced by a pair of water ligands [Cu—O = 2.439 (3) Å], the shorter Cu—O distance being compensated by the lengthened Cu—N distance [2.0443 (18), cf. 2.0100 (13) and 2.0122 (16) Å].     

1,3‐Propane­di­ammonium tetra­thio­tungstate and N,N,N′,N′‐tetra­methyl­ethyl­enedi­ammonium tetra­thio­tungstate

The title complexes, (C₃H₁₂N₂)[WS₄] and (C₆H₁₈N₂)[WS₄], contain tetrahedral [WS₄]²⁻ dianions, which accept a complex series of hydrogen bonds from the organic dications. The strength and number of these hydrogen bonds affect the W—S distances.     

Dibenzyl 2,2′‐(ethane‐1,2‐diyl­idene)dihydrazinecarbodithioate bis(di­methyl­formamide) solvate

The title compound, C₁₈H₁₈N₄S₄·2C₃H₇NO, crystallizes with the dibenzyl dihydrazinecarbodithioate mol­ecule residing on a crystallographic inversion centre. The mol­ecule adopts a trans conformation with respect to the central C—C single bond. The dihedral angle between the phenyl group and the thio­thio­semicarbazone unit is 74.1 (1)°.     

Hydro­gen‐bonded molecular ladders in trans‐1,2‐bis(2‐nitro­anilino)­cyclo­hexane

Crystals of the title compound, C₁₈H₂₀N₄O₄, contain equal numbers of (R,R) and (S,S) mol­ecules, but these are not precise enantiomorphs, neither are they related by crystallographic symmetry; in addition, each mol­ecule exhibits approximate, but not exact, twofold rotational symmetry. There are intramolecular N—H?O hydrogen bonds [N?O 2.609 (4)–2.638 (5) Å; N—H?O 125–132°] and the mol­ecules are linked into molecular ladders by C—H?O hydrogen bonds [C?O 3.306 (6)–3.386 (6) Å; C—H?O 146–160°].     

Intramolecular hydrogen‐bond‐directed coordination: trans‐bis(N‐benzoyl‐N′‐propyl­thio­urea‐κS)di­iodo­platinum(II) and trans‐bis(N‐benzoyl‐N′‐propyl­thio­urea‐κS)di­bromo­platinum(II)

In the title compounds, trans‐[PtI₂(C₁₁H₁₄N₂OS)₂], (I), and trans‐[PtBr₂(C₁₁H₁₄N₂OS)₂], (II), respectively, intramolecular N—H⋯O (propyl­amine side) hydrogen bonds in the potentially bidentate thio­urea ligands lock the carbonyl O atoms into six‐membered rings, determining the S‐mono­dentate mode of coordination of these ligands. Intramolecular N—H⋯X (X is I or Br) interactions (benzoyl­amine side) lead to slight distortions of the Pt^II coordination spheres from ideal square‐planar geometry. The Pt^II ion is located on an inversion centre in both structures.     

Bis(μ‐succinato‐O,O′:O′′,O′′′)bis[bis(2‐amino‐1,3‐benzothiazole‐N3)copper(II)]

In the title dimeric complex, [Cu₂(C₄H₄O₄)₂(C₇H₆N₂S)₄], which possesses a centre of symmetry, the Cu atoms are enclosed in a 14‐membered ring. They adopt a distorted square‐bipyramidal (4+2) coordination. The four closest donor atoms are two N atoms of 2‐amino­benzo­thiazole ligands and two O atoms of the succinate carboxylate groups. They form a square‐planar cis arrangement, with an average Cu—N distance of 2.003 (3) Å and Cu—O distances of 1.949 (3) and 1.965 (3) Å. Two longer Cu—O bonds of 2.709 (3) and 2.613 (3) Å involving the remaining O atoms of the carboxylate groups complete the sixfold coordination of the Cu atoms. The H atoms of each amino group of the 2‐amino­benzo­thiazole molecules form intra‐ and inter­molecular N—H?O hydrogen bonds. A nearly perpendicular inter­molecular C—H?Cg interaction (Cg is the centroid of the imidazole ring) is observed. The intramolecular Cu?Cu distance is 6.384 (2) Å.     

trans‐Di­aqua(C‐meso‐5,12‐di­methyl‐1,4,8,11‐tetra­aza­cyclo­tetra­decane‐N,N′,N′′,N′′′)copper(II) dichloride dihydrate

The crystal structure of the title complex, [Cu(C₁₂H₂₈N₄)(H₂O)₂]Cl₂·2H₂O, has been determined. The Cu^II atom is octahedrally coordinated by the four N atoms of the tetradentate macrocyclic ligand in equatorial positions and by the O atoms of two water mol­ecules in axial positions. The crystal structure is stabilized by a three‐dimensional network of hydrogen bonds.     

Bis(tetra‐n‐butylammonium) bis(μ‐1,2‐dicyanoethene‐1,2‐dithiolato‐κ3S,S′:S′)bis[(1,2‐dicyanoethene‐1,2‐dithiolato‐κ2S,S′)cobalt(III)]

In the title compound, (C₁₆H₃₆N)₂[Co(C₄N₂S₂)₂]₂, pairs of [Co(C₄N₂S₂)₂]^? anions combine to form discrete crystallographically centrosymmetric dimers, which stack along the c axis, surrounded by the counter‐cations. The metal atom in the anion has a five‐coordinate distorted square‐pyramidal geometry.     

An organopalladium(II) compound including enolate oxy­gen‐ and sp3‐carbon‐bound 1,3‐di­methyl­barbiturate ligands: (1,2‐di­amino­ethane)­bis(1,3‐di­methyl­barbiturato)­palladium(II) 5.5‐hydrate

In the title compound, [Pd(C₆H₇N₂O₃)₂(C₂H₈N₂)]·5.5H₂O, the Pd atom is coordinated by two 1,3‐di­methyl­barbiturate anions through a deprotonated tetrahedral carbon and the enolate oxy­gen. The Pd—N bond length of 2.078 (2) Åtrans to the C atom is shorter than the Pt—N distance of 2.098 (3) Å in the Pt analog.     

Bis(tetraphenylphosphonium) bis[cis‐1,2‐bis(methoxycarbonyl)ethylenedithiolato‐κ2S,S′]nickelate(II) and bis(tetraphenylphosphonium) bis[cis‐1,2‐bis(methoxycarbonyl)ethylenedithiolato‐κ2S,S′]nickelate(III) iodide

The crystal structures of the title compounds, (C₂₄H₂₀P)₂[Ni(C₆H₆O₄S₂)₂], (I), and (C₂₄H₂₀P)₂[Ni(C₆H₆O₄S₂)₂]I, (II), in the diamagnetic reduced (2–) and paramagnetic oxidized (1–) states, are reported at 200 and 293 K, respectively. In both compounds, the Ni atom lies on an inversion centre and the NiS₄ coordination is thus required to be exactly planar. In the diamagnetic complex, (I), the Ni—S distances are 2.1818 (7) and 2.1805 (6) Å, while they are 2.1481 (6) and 2.1392 (5) Å in the paramagnetic complex, (II). This results from both the different complex core oxidation states and the different conformations of the methoxycarbonyl groups.     

N,N′‐Bis­(dipiperidin‐1‐yl­methyl­ene)propane‐1,3‐di­amine and N,N′‐bis(1,3‐di­methyl­per­hydro­pyrimidin‐2‐yl­idene)­propane‐1,3‐di­amine

The molecular structures of the title compounds, C₂₅H₄₆N₆ and C₁₅H₃₀N₆, respectively, show the two guanidyl moieties each connected by propyl bridges. The different substitution pattern of the guanidyl groups has no influence on the distinct localization of their C=N double bonds. Both compounds exhibit approximate twofold symmetry and the crystal packing shows no prominent hydrogen‐bonding interactions.     

(1,3‐Dimethylimidazolidine‐2‐selone‐κSe)bis(1,10‐phenanthroline‐κ2N,N′)copper(II) bis(perchlorate) and bis(2,2′‐bipyridyl‐κ2N,N′)(imidazolidine‐2‐thione‐κS)copper(II) bis(perchlorate)

In the first title salt, [Cu(C₁₂H₈N₂)₂(C₅H₁₀N₂Se)](ClO₄)₂, the Cu^II centre occupies a distorted trigonal–bipyramidal environment defined by four N donors from two 1,10‐phenanthroline (phen) ligands and by the Se donor of a 1,3‐dimethylimidazolidine‐2‐selone ligand, with the equatorial plane defined by the Se and by two N donors from different phen ligands and the axial sites occupied by the two remaining N donors, one from each phen ligand. The Cu—N distances span the range 1.980 (10)–2.114 (11) Å and the Cu—Se distance is 2.491 (3) Å. Intermolecular π–π contacts between imidazolidine rings and the central rings of phen ligands generate chains of cations. In the second salt, [Cu(C₁₀H₈N₂)₂(C₃H₆N₂S)](ClO₄)₂, the Cu^II centre occupies a similar distorted trigonal–bipyramidal environment comprising four N donors from two 2,2′‐bipyridyl (bipy) ligands and an S donor from an imidazolidine‐2‐thione ligand. The equatorial plane is defined by the S donor and two N donors from different bipy ligands. The Cu—N distances span the range 1.984 (6)–2.069 (7) Å and the Cu—S distance is 2.366 (3) Å. Intermolecular π–π contacts between imidazolidine and pyridyl rings form chains of cations. A major difference between the two structures is due to the presence in the second complex of two N—H...O hydrogen bonds linking the imidazolidine N—H hydrogen‐bond donors to perchlorate O‐atom acceptors.     

Bis(1,3‐di­phenyl­propane‐1,3‐dionato‐O,O′)(di­phenyl sulfoxide‐O)dioxouranium(VI)

In the title complex, [UO₂(dbm)₂(PhSOPh)] or [UO₂(C₁₅H₁₁O₂)(C₁₂H₁₀OS)], where dbm is 1,3‐di­phenyl­propane‐1,3‐dionate, the U atom is surrounded by seven O atoms to give a distorted pentagonal bipyramidal geometry. The U—O_uranyl and U—O_dbm distances (dbm is 1,3‐di­phenyl­propane‐1,3‐dionate) are in the ranges 1.760 (6)–1.776 (5) and 2.308 (4)–2.417 (4) Å, respectively, while the U—O_sulfoxide distance is 2.427 (4) Å.     

Bis(1,5‐di­aza­cyclo­octane‐N,N′)nickel(II) dibromide

The crystal structure of the title complex, [Ni(C₆H₁₄N₂)₂]Br₂, consists of discrete [Ni(C₆H₁₄N₂)₂]²⁺ cations and bromide counter‐anions. The Ni^II ion is at the center of symmetry and is four‐coordinated by four nitro­gen donors of the mesocyclic ligand 1,5‐di­aza­cyclo­octane (DACO) [Ni—N 1.935 (2)–1.937 (2) Å]. The coordination geometry of Ni^II can be considered as square planar and both DACO ligands take the boat–chair conformation. The bromide anions are hydrogen bonded with the nitro­gen donors of the ligands to form a macrocycle‐like ring system.     

A benzene‐rich pseudopolymorph of bis[μ‐1,3‐bis(pentafluorophenyl)propane‐1,3‐dionato]‐κ3O,O′:O′;κ3O:O,O′‐bis{aqua[1,3‐bis(pentafluorophenyl)propane‐1,3‐dionato‐κ2O,O′]nickel(II)} benzene tetrasolvate

The title complex comprises two Ni²⁺ ions, four fluorinated ligands and two water molecules in a centrosymmetric dinuclear complex. This compound was crystallized from benzene–CH₂Cl₂, and two types of crystals, viz. the title benzene tetrasolvate, [Ni₂(C₁₅HF₁₀O₂)₄(H₂O)₂]·4C₆H₆, (I), and the previously reported benzene disolvate, [Ni₂(C₁₅HF₁₀O₂)₄(H₂O)₂]·2C₆H₆, (II) [Hori et al. (2009). Bull. Chem. Soc. Jpn, 82 , 96–98], were obtained as pseudopolymorphs. In the crystal structure of (I), the four benzene solvent molecules interact closely with all the pentafluorophenyl groups of the complex through arene–perfluoroarene interactions. The molecular structures of the two compounds show essentially the same conformation, although the benzene molecules are accommodated in a columnar packing in (I), while they are isolated from each other in (II).     

3‐Acetoxy­cyclo­hex‐4‐ene‐1,2‐di­carboxyl­ic anhydride

The title compound, C₁₀H₁₀O₅, was found to exist as the endo–cis isomer with a pair of enantiomers in the asymmetric unit. The cyclo­hexene ring is folded about the methyl­ene‐to‐CH(acetoxy) vector to give a boat conformation.     

Di‐μ‐hydroxido‐bis{[bis(6‐methyl‐2‐pyridylmethyl)(2‐phenylethyl)amine‐κ3N′,N′′,N′′′]copper(II)} bis(perchlorate)

The title compund, [Cu₂(OH)₂(C₂₂H₂₅N₃)₂](ClO₄)₂, is a copper(II) dimer, with two [CuL]²⁺ units [L is bis(6‐methyl‐2‐pyridylmethyl)(2‐phenylethyl)amine] bridged by hydroxide groups to define the {[CuL](μ‐OH)₂[CuL]}²⁺ cation. Charge balance is provided by perchlorate counter‐anions. The cation has a crystallographic inversion centre halfway between the Cu^II ions, which are separated by 3.0161 (8) Å. The central core of the cation is an almost regular Cu₂O₂ parallelogram of sides 1.931 (2) and 1.935 (2) Å, with a Cu—O—Cu angle of 102.55 (11)°. The coordination geometry around each Cu^II centre can be best described as a square‐based pyramid, with three N atoms from L ligands and two hydroxide O atoms completing the coordination environment. Each cationic unit is hydrogen bonded to two perchlorate anions by means of hydroxide–perchlorate O—H...O interactions.