Hydrogen‐bonded sheets in benzylmethylammonium hydrogen maleate

In the title compound, C₈H₁₂N⁺·C₄H₃O₄⁻, there is a short and almost linear but asymmetric O—H...O hydrogen bond in the anion. The ions are linked into C₂²(6) chains by two short and nearly linear N—H...O hydrogen bonds and the chains are further weakly linked into sheets by a single C—H...O hydrogen bond.     

Hydrogen‐bond‐directed supramolecular arrays in 4,4′‐bipyridinium tetrachloroterephthalate dihydrate and bis(1,10‐phenanthrolinium) tetrachloroterephthalate tetrachloroterephthalic acid trihydrate

The title compounds, C₁₀H₁₀N₂²⁺·C₈Cl₄O₄²⁻·2H₂O, (I), and 2C₁₂H₉N₂⁺·C₈Cl₄O₄²⁻·C₈H₂Cl₄O₄·3H₂O, (II), both crystallize as charge‐transfer organic salts with the dianionic or neutral acid components lying on inversion centres. The acid and base subunits in (I) arrange alternately to generate a linear tape motif via N—H...O hydrogen bonds; these tapes are further combined into a three‐dimensional architecture through multiple O—H...O and C—H...O interactions involving solvent water molecules. In contrast, the neutral and anionic acid components in (II) are linked to form a zigzag chain by means of O—H...O hydrogen bonds between acid groups, with dangling 1,10‐phenanthrolinium units connected to these chains by carboxylate–pyridinium interactions with R₂²(7) hydrogen‐bond notation. Adjacent chains are further extended to result in a two‐dimensional corrugated layer network viaπ–π interactions. Inter‐ion Cl...O interactions are also found in both (I) and (II).     

Hydrogen‐bonding patterns in two aroylthiocarbamates and two aroylimidothiocarbonates

In O‐ethyl N‐benzoylthiocarbamate, C₁₀H₁₁NO₂S, the molecules are linked into sheets by a combination of two‐centre N—H...O and C—H...S hydrogen bonds and a three‐centre C—H...(O,S) hydrogen bond. A combination of two‐centre N—H...O and C—H...O hydrogen bonds links the molecules of O‐ethyl N‐(4‐methylbenzoyl)thiocarbamate, C₁₁H₁₃NO₂S, into chains of rings, which are linked into sheets by an aromatic π–π stacking interaction. In O,S‐diethyl N‐(4‐methylbenzoyl)imidothiocarbonate, C₁₃H₁₇NO₂S, pairs of molecules are linked into centrosymmetric dimers by pairs of symmetry‐related C—H...π(arene) hydrogen bonds, while the molecules of O,S‐diethyl N‐(4‐chlorobenzoyl)imidothiocarbonate, C₁₂H₁₄ClNO₂S, are linked by a single C—H...O hydrogen bond into simple chains, pairs of which are linked by an aromatic π–π stacking interaction to form a ladder‐type structure.     

Four 7‐aryl‐substituted pyrido[2,3‐d]pyrimidine‐2,4(1H,3H)‐diones: similar molecular structures but different crystal structures

Molecules of 1,3‐dimethyl‐7‐(4‐methylphenyl)pyrido[2,3‐d]pyrimidine‐2,4(1H,3H)‐dione, C₁₆H₁₅N₃O₂, (I), are linked by paired C—H...O hydrogen bonds to form centrosymmetric R₂²(10) dimers, which are linked into chains by a single π–π stacking interaction. A single C—H...O hydrogen bond links the molecules of 7‐(biphenyl‐4‐yl)‐1,3‐dimethylpyrido[2,3‐d]pyrimidine‐2,4(1H,3H)‐dione, C₂₁H₁₇N₃O₂, (II), into C(10) chains, which are weakly linked into sheets by a π–π stacking interaction. In 7‐(4‐fluorophenyl)‐3‐methylpyrido[2,3‐d]pyrimidine‐2,4(1H,3H)‐dione, C₁₄H₁₀FN₃O₂, (III), an N—H...O hydrogen bond links the molecules into C(6) chains, which are linked into sheets by a π–π stacking interaction. The molecules of 7‐(4‐methoxyphenyl)‐3‐methylpyrido[2,3‐d]pyrimidine‐2,4(1H,3H)‐dione, C₁₅H₁₃N₃O₃, (IV), are also linked into C(6) chains by an N—H...O hydrogen bond, but here the chains are linked into sheets by a combination of two independent C—H...π(arene) hydrogen bonds.     

Tris(2,2′‐bipyridine)iron(II) bis(1,1,3,3‐tetracyano‐2‐ethoxypropenide) dihydrate: chiral hydrogen‐bonded frameworks interpenetrate in three dimensions

In the title compound, [Fe(C₁₀H₈N₂)₃](C₉H₅N₄O)₂·2H₂O, the chiral cations lie across twofold rotation axes in the space group C2/c. The anions and the water molecules are linked by two independent O—H...N hydrogen bonds to form C₂²(8) chains, and these chains are linked by the cations via C—H...N and C—H...O hydrogen bonds to form two interpenetrating three‐dimensional frameworks, each of which contains only one enantiomeric form of the chiral cation.     

Conformational isomers of the [(5‐methyl‐2‐pyridinio)aminomethylene]diphosphonate dianion and [(5‐methyl‐2‐pyridyl)aminomethylene]diphosphonate trianion in salts with 4‐aminopyridine and ammonia

The crystal structures of two salts, products of the reactions between [(5‐methyl‐2‐pyridyl)aminomethylene]bis(phosphonic acid) and 4‐aminopyridine or ammonia, namely bis(4‐aminopyridinium) hydrogen [(5‐methyl‐2‐pyridinio)aminomethylene]diphosphonate 2.4‐hydrate, 2C₅H₇N₂⁺·C₇H₁₀N₂O₆P₂²⁻·2.4H₂O, (I), and triammonium hydrogen [(5‐methyl‐2‐pyridyl)aminomethylene]diphosphonate monohydrate, 3NH₄⁺·C₇H₉N₂O₆P₂³⁻·H₂O, (II), have been determined. In (I), the Z configuration of the ring N—C and amino N—H bonds of the bisphosphonate dianion with respect to the C_ring—N_amino bond is consistent with that of the parent zwitterion. Removing the H atom from the pyridyl N atom results in the opposite E configuration of the bisphosphonate trianion in (II). Compound (I) exhibits a three‐dimensional hydrogen‐bonded network, in which 4‐aminopyridinium cations and water molecules are joined to ribbons composed of anionic dimers linked by O—H...O and N—H...O hydrogen bonds. The supramolecular motif resulting from a combination of these three interactions is a common phenomenon in crystals of all of the Z‐isomeric zwitterions of 4‐ and 5‐substituted (2‐pyridylaminomethylene)bis(phosphonic acid)s studied to date. In (II), ammonium cations and water molecules are linked to chains of trianions, resulting in the formation of double layers.     

4‐Iodo­anilinium 3‐nitro­phthalate(1–): tripartite sheets built from O—H...O and N—H...O hydrogen bonds

In the title compound, 4‐iodoanilinium 2‐carboxy‐6‐nitrobenzoate, C₆H₇IN⁺·C₈H₄NO₆⁻, the anions are linked by an O—H...O hydrogen bond [H...O = 1.78 Å, O...O = 2.614 (3) Å and O—H...O = 171°] into C(7) chains, and these chains are linked by two two‐centre N—H...O hydrogen bonds [H...O = 1.86 and 1.92 Å, N...O = 2.700 (3) and 2.786 (3) Å, and N—H...O = 153 and 158°] and one three‐centre N—H...(O)₂ hydrogen bond [H...O = 2.02 and 2.41 Å, N...O = 2.896 (3) and 2.789 (3) Å, N—H...O = 162 and 105°, and O...H...O = 92°], thus forming sheets con­taining R(6), R(8), R(13) and R(18) rings.     

Tolterodinium (+)‐(2R,3R)‐hydrogen tartrate

In the crystal structure of (R)‐N,N‐diisopropyl‐3‐(2‐hydroxy‐5‐methyl­phenyl)‐3‐phenyl­propyl­aminium (2R,3R)‐hydrogen tartrate, C₂₂H₃₂NO⁺·C₄H₅O₆⁻, the hydrogen tartrate anions are linked by O—H⋯O hydrogen bonds to form helical chains built from (9) rings. These chains are linked by the tolterodine molecules via N—H⋯O and O—H⋯O hydrogen bonds to form separate sheets parallel to the (101) plane.     

(S)‐5‐Benzylimidazolidine‐2,4‐dione monohydrate

The crystal structure of the title compound, C₁₀H₁₀N₂O₂·H₂O, also known as l ‐5‐benzylhydantoin monohydrate, is described in terms of two‐dimensional supramolecular arrays built up from infinite chains assembled via N—H...O and O—H...O hydrogen bonds among the organic molecules and solvent water molecules, with graph‐set R³₃(10)C(5)C²₂(6). The hydrogen‐bond network is reinforced by stacking of the layers through C—H...π interactions.     

1:1 Adducts of 2,2′‐[isopropylidenebis(p‐phenyleneoxy)]diacetic acid with dimethylammonium and 4,4′‐bipyridine

The title compounds, dimethylammonium 2‐{4‐[1‐(4‐carboxymethoxyphenyl)‐1‐methylethyl]phenoxy}acetate, C₂H₈N⁺·C₁₉H₁₉O₆⁻, (I), and 2,2′‐[isopropylidenebis(p‐phenyleneoxy)]diacetic acid–4,4′‐bipyridine (1/1), C₁₉H₂₀O₆·C₁₀H₈N₂, (II), are 1:1 adducts of 2,2′‐[isopropylidenebis(p‐phenyleneoxy)]diacetic acid (H₂L) with dimethylammonium or 4,4′‐bipyridine. The component ions in (I) are linked by N—H...O, O—H...O and C—H...O hydrogen bonds into continuous two‐dimensional layers parallel to the (001) plane. Adjacent layers are stacked via C—H...O hydrogen bonds into a three‐dimensional network with an –ABAB– alternation of the two‐dimensional layers. In (II), two H₂L molecules, one bipy molecule and two half bipy molecules are linked by O—H...N hydrogen bonds into one‐dimensional chains and rectanglar‐shaped rings. They are assembled viaπ–π stacking interactions and C—H...O hydrogen bonds into an intriguing zero‐dimensional plus one‐dimensional poly(pseudo)rotaxane motif.     

Three‐dimensional networks in bis(imidazolium) 2,2′‐dithiodibenzoate and 4‐methylimidazolium 2‐[(2‐carboxyphenyl)disulfanyl]benzoate

Cocrystallization of imidazole or 4‐methylimidazole with 2,2′‐dithiodibenzoic acid from methanol solution yields the title 2:1 and 1:1 organic salts, 2C₃H₅N₂⁺·C₁₄H₁₀O₄S₂²⁻, (I), and C₄H₇N₂⁺·C₁₄H₁₀O₄S₂⁻, (II), respectively. Compound (I) crystallizes in the monoclinic C2/c space group with the mid‐point of the S—S bond lying on a twofold axis. The component ions in (I) are linked by intermolecular N—H...O hydrogen bonds to form a two‐dimensional network, which is further linked by C—H...O hydrogen bonds into a three‐dimensional network. In contrast, by means of N—H...O, N—H...S and O—H...O hydrogen bonds, the component ions in (II) are linked into a tape and adjacent tapes are further linked by π–π, C—H...O and C—H...π interactions, resulting in a three‐dimensional network.     

(6‐Oxido‐2‐oxo‐1,2‐dihydropyrimidine‐5‐carboxylato‐κ2O5,O6)bis[2‐(2‐pyridyl)‐1H‐benzimidazole‐κ2N2,N3]manganese(II) monohydrate

In the title compound, [Mn(C₅H₂N₂O₄)(C₁₂H₉N₃)₂]·H₂O, the Mn^II centre is surrounded by three bidentate chelating ligands, namely, one 6‐oxido‐2‐oxo‐1,2‐dihydropyrimidine‐5‐carboxylate (or uracil‐5‐carboxylate, Huca²⁻) ligand [Mn—O = 2.136 (2) and 2.156 (3) Å] and two 2‐(2‐pyridyl)‐1H‐benzimidazole (Hpybim) ligands [Mn—N = 2.213 (3)–2.331 (3) Å], and it displays a severely distorted octahedral geometry, with cis angles ranging from 73.05 (10) to 105.77 (10)°. Intermolecular N—H...O hydrogen bonds both between the Hpybim and the Huca²⁻ ligands and between the Huca²⁻ ligands link the molecules into infinite chains. The lattice water molecule acts as a hydrogen‐bond donor to form double O...H—O—H...O hydrogen bonds with the Huca²⁻ O atoms, crosslinking the chains to afford an infinite two‐dimensional sheet; a third hydrogen bond (N—H...O) formed by the water molecule as a hydrogen‐bond acceptor and a Hpybim N atom further links these sheets to yield a three‐dimensional supramolecular framework. Possible partial π–π stacking interactions involving the Hpybim rings are also observed in the crystal structure.     

Supramolecular aggregation in three 4‐aryl‐6‐(1H‐indol‐3‐yl)‐3‐methyl‐1‐phenyl‐1H‐pyrazolo[3,4‐b]pyridine‐5‐carbonitriles

Both 6‐(1H‐indol‐3‐yl)‐3‐methyl‐4‐(4‐methylphenyl)‐1‐phenyl‐1H‐pyrazolo[3,4‐b]pyridine‐5‐carbonitrile and 6‐(1H‐indol‐3‐yl)‐3‐methyl‐4‐(4‐methoxyphenyl)‐1‐phenyl‐1H‐pyrazolo[3,4‐b]pyridine‐5‐carbonitrile crystallize from dimethylformamide solutions as stoichiometric 1:1 solvates, viz. C₂₉H₂₁N₅·C₃H₇NO, (I), and C₂₉H₂₁N₅O·C₃H₇NO, (II), respectively; however, 6‐(1H‐indol‐3‐yl)‐3‐methyl‐1‐phenyl‐4‐(3,4,5‐trimethoxyphenyl)‐1H‐pyrazolo[3,4‐b]pyridine‐5‐carbonitrile, C₃₁H₂₅N₅O₃, (III), crystallizes in the unsolvated form. The heterocyclic components of (I) are linked by C—H...π(arene) hydrogen bonds to form cyclic centrosymmetric dimers, from which the solvent molecules are pendent, linked by N—H...O hydrogen bonds. In (II), the heterocyclic components are linked by a combination of C—H...N and C—H...π(arene) hydrogen bonds into chains containing two types of centrosymmetric ring, and the pendent solvent molecules are linked to these chains by N—H...O hydrogen bonds. Molecules of (III) are linked into simple C(12) chains by an N—H...O hydrogen bond, and these chains are weakly linked into pairs by an aromatic π–π stacking interaction.     

The 1:1 inclusion compounds zolmitriptan–benzene and zolmitriptan–phenol

In the benzene and phenol solvates of (S)‐4‐{3‐[2‐(dimethylamino)ethyl]‐1H‐indol‐5‐ylmethyl}oxazolidin‐2‐one, viz. C₁₆H₂₁N₃O₂·C₆H₆, (I), and C₁₆H₂₁N₃O₂·C₆H₅OH, (II), the host molecule has three linked residues, namely a planar indole ring system, an ethylamine side chain and an oxazolidinone system. It has comparable features to that of sumatriptan, although the side‐chain orientations of (I) and (II) differ from those of sumatriptan. Both (I) and (II) have host–guest‐type structures. The host molecule in (I) and (II) has an L‐shaped form, with the oxazolidinone ring occupying the base and the remainder of the molecule forming the upright section. In (I), each benzene guest molecule is surrounded by four host molecules, and these molecules are linked by a combination of N—H...N, N—H...O and C—H...O hydrogen bonds into chains of edge‐fused R₄⁴(33) rings. In (II), two independent molecules are present in the asymmetric unit, with similar conformations. The heterocyclic components are connected through N—H...N, N—H...O and C—H...O interactions to form chains of edge‐fused R₆⁴(38) rings, from which the phenol guest molecules are pendent, linked by O—H...O hydrogen bonds. The structures are further stabilized by extensive C—H...π interactions.     

1‐Carboxymethyl‐3‐methyl‐1H‐imidazol‐3‐ium chloride 2‐(3‐methyl‐1H‐imidazol‐3‐ium‐1‐yl)acetate monohydrate: a crystal stabilized by imidazolium zwitterions

The title compound, C₆H₉N₂O₂⁺·Cl⁻·C₆H₈N₂O₂·H₂O, contains one 2‐(3‐methyl‐1H‐imidazol‐3‐ium‐1‐yl)acetate inner salt molecule, one 1‐carboxymethyl‐3‐methyl‐1H‐imidazol‐3‐ium cation, one chloride ion and one water molecule. In the extended structure, chloride anions and water molecules are linked via O—H...Cl hydrogen bonds, forming an infinite one‐dimensional chain. The chloride anions are also linked by two weak C—H...Cl interactions to neighbouring methylene groups and imidazole rings. Two imidazolium moieties form a homoconjugated cation through a strong and asymmetric O—H...O hydrogen bond of 2.472 (2) Å. The IR spectrum shows a continuous D‐type absorption in the region below 1300 cm⁻¹ and is different to that of 1‐carboxymethyl‐3‐methylimidazolium chloride [Xuan, Wang & Xue (2012). Spectrochim. Acta Part A, 96 , 436–443].     

Three N2‐benzoyl­oxybenz­amidines: sheet structures built from hard and soft hydrogen bonds and aromatic π–π stacking interactions

Molecules of the title compounds N²‐(benzoyl­oxy)­benz­ami­dine, C₁₄H₁₂N₂O₂, (I), N²‐(2‐hydroxy­benzoyl­oxy)­benz­ami­dine, C₁₄H₁₂N₂O₃, (II), and N²‐benzoyloxy‐2‐hydroxybenzamidine, C₁₄H₁₂N₂O₃, (III), all have extended chain conformations, with the aryl groups remote from one another. In (I), the mol­ecules are linked into chains by a single N—H⋯N hydrogen bond [H⋯N = 2.15 Å, N⋯N = 3.029 (2) Å and N—H⋯N = 153°] and these chains are linked into sheets by means of aromatic π–π stacking interactions. There is one intramolecular O—H⋯O hydrogen bond in (II), and a combination of one three‐centre N—H⋯(N,O) hydrogen bond [H⋯N = 2.46 Å, H⋯O = 2.31 Å, N⋯N = 3.190 (2) Å, N⋯O = 3.146 (2) Å, N—H⋯N = 138° and N—H⋯O = 154°] and one two‐centre C—H⋯O hydrogen bond [H⋯O = 2.46 Å, C⋯O = 3.405 (2) Å and C—H⋯O = 173°] links the mol­ecules into sheets. In (III), an intramolecular O—H⋯N hydrogen bond and two N—H⋯O hydrogen bonds [H⋯O = 2.26 and 2.10 Å, N⋯O = 2.975 (2) and 2.954 (2) Å, and N—H⋯O = 138 and 163°] link the molecules into sheets.     

Unusual hydrate stabilization in the two‐dimensional layered structure of quinacrinium bis(2‐carboxy‐4,5‐dichlorobenzoate) tetrahydrate,a proton‐transfer compound of the drug quinacrine

The crystal structure of the hydrated proton‐transfer compound of the drug quinacrine [rac‐N′‐(6‐chloro‐2‐methoxyacridin‐9‐yl)‐N,N‐diethylpentane‐1,4‐diamine] with 4,5‐dichlorophthalic acid, C₂₃H₃₂ClN₃O²⁺·2C₈H₃Cl₂O₄⁻·4H₂O, has been determined at 200 K. The four labile water molecules of solvation in the structure form discrete ...O—H...O—H... hydrogen‐bonded chains parallel to the quinacrine side chain, the two N—H groups of which act as hydrogen‐bond donors for two of the water acceptor molecules. The other water molecules, as well as the acridinium H atom, also form hydrogen bonds with the two anion species and extend the structure into two‐dimensional sheets. Between these sheets there are also weak cation–anion and anion–anion π–π aromatic ring interactions. This structure represents the third example of a simple quinacrine derivative for which structural data are available but differs from the other two in that it is unstable in the X‐ray beam due to efflorescence, probably associated with the destruction of the unusual four‐membered water chain structures.     

Two three‐dimensional networks in the binary molecular adducts 4‐methylimidazolium hydrogen terephthalate and bis(4‐methylimidazolium) terephthalate

Both the 1:1 and 2:1 molecular adducts of 4‐methylimidazole (4‐MeIm) and terephthalic acid (H₂TPA) are organic salts, viz. C₄H₇N₂⁺·C₈H₅O₄⁻, (I), and 2C₄H₇N₂⁺·C₈H₄O₄²⁻, (II), respectively. The component ions in (I) are linked by N—H...O and O—H...O hydrogen bonds into continuous two‐dimensional layers built from R₆⁴(32) hydrogen‐bond motifs running parallel to the (100) plane. These adjacent two‐dimensional layers are in turn linked by a combination of C—H...O, C—H...π and π–π interactions into a three‐dimensional network. In the crystal structure of (II), with the anion located on an inversion centre, only N—H...O hydrogen bonds result in two‐dimensional layers built from R₈⁸(42) hydrogen‐bond motifs running parallel to the (102) plane. Being similar to those in (I), these layers are also linked by means of C—H...O, C—H...π and π–π interactions, forming a three‐dimensional network. This study indicates that, on occasion, a change of the reactant concentration can exert a pivotal influence on the construction of supramolecular structures based on hydrogen bonds.     

Cocrystals of 6‐propyl‐2‐thiouracil: N—H...O versus N—H...S hydrogen bonds

In order to investigate the relative stability of N—H...O and N—H...S hydrogen bonds, we cocrystallized the antithyroid drug 6‐propyl‐2‐thiouracil with two complementary heterocycles. In the cocrystal pyrimidin‐2‐amine–6‐propyl‐2‐thiouracil (1/2), C₄H₅N₃·2C₇H₁₀N₂OS, (I), the `base pair' is connected by one N—H...S and one N—H...N hydrogen bond. Homodimers of 6‐propyl‐2‐thiouracil linked by two N—H...S hydrogen bonds are observed in the cocrystal N‐(6‐acetamidopyridin‐2‐yl)acetamide–6‐propyl‐2‐thiouracil (1/2), C₉H₁₁N₃O₂·2C₇H₁₀N₂OS, (II). The crystal structure of 6‐propyl‐2‐thiouracil itself, C₇H₁₀N₂OS, (III), is stabilized by pairwise N—H...O and N—H...S hydrogen bonds. In all three structures, N—H...S hydrogen bonds occur only within R₂²(8) patterns, whereas N—H...O hydrogen bonds tend to connect the homo‐ and heterodimers into extended networks. In agreement with related structures, the hydrogen‐bonding capability of C=O and C=S groups seems to be comparable.     

A two‐dimensional network in the molecular salt 2‐methylimidazolium hydrogen glutarate,and three‐dimensional networks in the salts 2‐methylimidazolium hydrogen succinate and 2‐methylimidazolium hydrogen adipate monohydrate

All three title compounds, C₄H₇N₂⁺·C₄H₅O₄⁻, (I), C₄H₇N₂⁺·C₅H₇O₄⁻, (II), and C₄H₇N₂⁺·C₆H₉O₄⁻·H₂O, (III), can be regarded as 1:1 organic salts. The dicarboxylic acids join through short acid bridges into infinite chains. Compound (I) crystallizes in the noncentrosymmetric Cmc2₁ space group and the asymmetric unit consists of a hydrogen succinate anion located on a mirror plane and a 2‐methylimidazolium cation disordered across the same mirror. The other two compounds crystallize in the triclinic P space group. The carboxylic acid H atom in (II) is disordered over both ends of the anion and sits on inversion centres between adjacent anions, forming symmetric short O...H...O bridges. Two independent anions in (III) sit across inversion centres, again with the carboxylic acid H atom disordered in short O...H...O bridges. The molecules in all three compounds are linked into two‐dimensional networks by combinations of imidazolium–carboxylate N⁺—H...O and carboxylate–carboxylate O—H...O hydrogen bonds. The two‐dimensional networks are further linked into three‐dimensional networks by C—H...O hydrogen bonds in (I) and by O_water—H...O hydrogen bonds in (III). According to the ΔpK_a rule, such 1:1 types of organic salts can be expected unambiguously. However, a 2:1 type of organic salt may be more easily obtained in (II) and (III) than in (I).