4,8‐Di­methoxy‐1‐naphthalene­methanol

The title compound, C₁₃H₁₄O₃, crystallized in the centrosymmetric space group C2/c with one mol­ecule as the asymmetric unit. Each hydroxyl O atom is involved in hydrogen bonds with two other hydroxyl O atoms. The resulting chains of interactions propagate along [001]. In these interactions, the hydroxyl H atoms are disordered and the O?O distances are 2.648 (2) and 2.698 (2) Å. Two leading intermolecular C—H?O interactions have H?O distances of 2.80 and 2.84 Å and C—H?O angles of 136 and 144°; these interactions form chain and ring patterns. Taken together with the hydrogen bonds, they result in a three‐dimensional network.     

Hydro­gen bonds and C—H⋯O interactions in 2,2′‐dimethoxybiphenyl‐5,5′‐dimethanol at 150 K

The title compound, C₁₆H₁₈O₄, crystallized in the centrosymmetric space group P2₁/c with one mol­ecule in the asymmetric unit. The two hydroxyl‐H atoms are ordered, and are involved in intermolecular hydrogen bonds with O_donor?O_acceptor distances of 2.761 (1) and 2.699 (1) Å, and O—H?O angles of 157 (2) and 168 (2)°. Seven leading intermolecular C—H?O interactions have H?O distances ranging from 2.41 to 2.76 Å and C—H?O angles ranging from 125 to 170°. The hydrogen bonds and C—H?O interactions form chain and ring patterns, resulting in a richly three‐dimensional network. The bi­phenyl twist angle is 67.2 (1)°.     

Hydro­gen bonding and C—H⋯O interactions in 3‐(3‐amino­phthal­imido)phthalic acid dihydrate

The title compound, C₁₆H₁₀N₂O₆·2H₂O, crystallized in the centrosymmetric triclinic space group P with one organic mol­ecule and two water mol­ecules as the asymmetric unit. Eight intermolecular hydrogen bonds have donor?acceptor distances in the range 2.602 (2)–3.289 (2) Å, with angles in the range 137 (2)–177 (2)°. These generate a three‐dimensional hydrogen‐bond network. There is a single intramolecular hydrogen bond. There are six significant intermolecular C—H?O interactions with H?O distances in the range 2.39–2.74 Å, and C—H?O angles in the range 131–157°.     

Crystallographic study of self‐organization in the solid state including quasi‐aromatic pseudo‐ring stacking interactions in 1‐benzoyl‐3‐(3,4‐dimethoxyphenyl)thiourea and 1‐benzoyl‐3‐(2‐hydroxypropyl)thiourea

1‐Benzoylthioureas contain both carbonyl and thiocarbonyl functional groups and are of interest for their biological activity, metal coordination ability and involvement in hydrogen‐bond formation. Two novel 1‐benzoylthiourea derivatives, namely 1‐benzoyl‐3‐(3,4‐dimethoxyphenyl)thiourea, C₁₆H₁₆N₂O₃S, (I), and 1‐benzoyl‐3‐(2‐hydroxypropyl)thiourea, C₁₁H₁₄N₂O₂S, (II), have been synthesized and characterized. Compound (I) crystallizes in the space group P , while (II) crystallizes in the space group P 2₁/c . In both structures, intramolecular N—H…O hydrogen bonding is present. The resulting six‐membered pseudo‐rings are quasi‐aromatic and, in each case, interact with phenyl rings via stacking‐type interactions. C—H…O, C—H…S and C—H…π interactions are also present. In (I), there is one molecule in the asymmetric unit. Pairs of molecules are connected via two intermolecular N—H…S hydrogen bonds, forming centrosymmetric dimers. In (II), there are two symmetry‐independent molecules that differ mainly in the relative orientations of the phenyl rings with respect to the thiourea cores. Additional strong hydrogen‐bond donor and acceptor –OH groups participate in the formation of intermolecular N—H…O and O—H…S hydrogen bonds that join molecules into chains extending in the [001] direction.     

Hydro­gen bonds and C—H⋯O interactions in 2‐(2‐methyl­benzyl)­malonic acid at 150 K

The title compound, C₁₁H₁₂O₄, crystallized in the centrosymmetric space group Pbca with one mol­ecule as the asymmetric unit. The two hydrogen bonds have O_D?O_A distances of 2.667 (2) and 2.628 (2) Å, and O—H?O angles of 179 (2) and 177 (2)°. Each hydrogen bond forms an R(8) cyclic dimer about a center of symmetry. The leading intermolecular C—­H?O interaction has an H?O distance of 2.66 Å and a C—H?O angle of 160°. Taken together with the hydrogen bonds, it results in a three‐dimensional network of inter­actions. The structure is compared with that of a close analog, benzyl­malonic acid.     

4‐Ethynyl‐4‐hydroxycyclohexan‐1‐one and 4‐ethynyl‐4‐hydroxy‐2,3,5,6‐tetramethylcyclohexa‐2,5‐dien‐1‐one

The title compounds, C₈H₁₀O₂, (I), and C₁₂H₁₄O₂, (II), occurred as by‐products in the controlled synthesis of a series of bis­(gem‐alkynols), prepared as part of an extensive study of synthon formation in simple gem‐alkynol derivatives. The two 4‐(gem‐alkynol)‐1‐ones crystallize in space group P2₁/c, (I) with Z′ = 1 and (II) with Z′ = 2. Both structures are dominated by O—H?O=C hydrogen bonds, which form simple chains in the cyclo­hexane derivative, (I), and centrosymmetric dimers, of both symmetry‐independent mol­ecules, in the cyclo­hexa‐2,5‐diene, (II). These strong synthons are further stabilized by C[triple‐bond]C—H?O=C, C_methylene—H?O(H) and C_methyl—H?O(H) interactions. The direct intermolecular interactions between donors and acceptors in the gem‐alkynol group, which characterize the bis­(gem‐alkynol) analogues of (I) and (II), are not present in the ketone derivatives studied here.     

Adducts of 1,1,1‐tris(4‐hydroxyphenyl)ethane with diamines: three‐dimensional hydrogen‐bonded frameworks formed with 1,6‐diaminohexane and 2,2′‐bipyridyl

The adduct 1,6‐di­amino­hexane–1,1,1‐tris(4‐hydroxy­phenyl)­ethane (1/2) is a salt {hexane‐1,6‐diyldiammonium–4‐[1,1‐bis(4‐hydroxyphenyl)ethyl]phenolate (1/2)}, C₆H₁₈N₂²⁺·2C₂₀H₁₇O₃^?, in which the cation lies across a centre of inversion in space group P. The anions are linked by two short O—H?O hydrogen bonds [H?O 1.74 and 1.76 Å, O?O 2.5702 (12) and 2.5855 (12) Å, and O—H?O 168 and 169°] into a chain containing two types of R(24) ring. Each cation is linked to four different anion chains by three N—H?O hydrogen bonds [H?O 1.76–2.06 Å, N?O 2.6749 (14)–2.9159 (14) Å and N—H?O 156–172°]. In the adduct 2,2′‐bipyridyl–1,1,1‐tris(4‐hydroxy­phenyl)­ethane (1/2), C₁₀H₈N₂·2C₂₀H₁₈O₃, the neutral di­amine lies across a centre of inversion in space group P2₁/n. The tris­(phenol) mol­ecules are linked by two O—H?O hydrogen bonds [H?O both 1.90 Å, O?O 2.7303 (14) and 2.7415 (15) Å, and O—H?O 173 and 176°] into sheets built from R(38) rings. Pairs of tris­(phenol) sheets are linked via the di­amine by means of a single O—H?N hydrogen bond [H?N 1.97 Å, O?N 2.7833 (16) Å and O—H?N 163°].     

2‐Ethyl‐6‐methylpyridin‐3‐ol and its salt bis(2‐ethyl‐3‐hydroxy‐6‐methylpyridinium) succinate

The title compounds, C₈H₁₁NO, (I), and 2C₈H₁₂NO⁺·C₄H₄O₄²⁻, (II), both crystallize in the monoclinic space group P2₁/c. In the crystal structure of (I), intermolecular O—H...N hydrogen bonds combine the molecules into polymeric chains extending along the c axis. The chains are linked by C—H...π interactions between the methylene H atoms and the pyridine rings into polymeric layers parallel to the ac plane. In the crystal structure of (II), the succinate anion lies on an inversion centre. Its carboxylate groups interact with the 2‐ethyl‐3‐hydroxy‐6‐methylpyridinium cations via intermolecular N—H...O hydrogen bonds with the pyridine ring H atoms and O—H...O hydrogen bonds with the hydroxy H atoms to form polymeric chains, which extend along the [01] direction and comprise R₄⁴(18) hydrogen‐bonded ring motifs. These chains are linked to form a three‐dimensional network through nonclassical C—H...O hydrogen bonds between the pyridine ring H atoms and the hydroxy‐group O atoms of neighbouring cations. π–π interactions between the pyridine rings and C—H...π interactions between the methylene H atoms of the succinate anion and the pyridine rings are also present in this network.     

N,N′‐Diethyl‐4‐nitrobenzene‐1,3‐diamine, 2,6‐bis(ethylamino)‐3‐nitrobenzonitrile and bis(4‐ethylamino‐3‐nitrophenyl) sulfone

N,N′‐Diethyl‐4‐nitrobenzene‐1,3‐diamine, C₁₀H₁₅N₃O₂, (I), crystallizes with two independent molecules in the asymmetric unit, both of which are nearly planar. The molecules differ in the conformation of the ethylamine group trans to the nitro group. Both molecules contain intramolecular N—H...O hydrogen bonds between the adjacent amine and nitro groups and are linked into one‐dimensional chains by intermolecular N—H...O hydrogen bonds. The chains are organized in layers parallel to (101) with separations of ca 3.4 Å between adjacent sheets. The packing is quite different from what was observed in isomeric 1,3‐bis(ethylamino)‐2‐nitrobenzene. 2,6‐Bis(ethylamino)‐3‐nitrobenzonitrile, C₁₁H₁₄N₄O₂, (II), differs from (I) only in the presence of the nitrile functionality between the two ethylamine groups. Compound (II) crystallizes with one unique molecule in the asymmetric unit. In contrast with (I), one of the ethylamine groups, which is disordered over two sites with occupancies of 0.75 and 0.25, is positioned so that the methyl group is directed out of the plane of the ring by approximately 85°. This ethylamine group forms an intramolecular N—H...O hydrogen bond with the adjacent nitro group. The packing in (II) is very different from that in (I). Molecules of (II) are linked by both intermolecular amine–nitro N—H...O and amine–nitrile N—H...N hydrogen bonds into a two‐dimensional network in the (10) plane. Alternating molecules are approximately orthogonal to one another, indicating that π–π interactions are not a significant factor in the packing. Bis(4‐ethylamino‐3‐nitrophenyl) sulfone, C₁₆H₁₈N₄O₆S, (III), contains the same ortho nitro/ethylamine pairing as in (I), with the position para to the nitro group occupied by the sulfone instead of a second ethylamine group. Each 4‐ethylamino‐3‐nitrobenzene moiety is nearly planar and contains the typical intramolecular N—H...O hydrogen bond. Due to the tetrahedral geometry about the S atom, the molecules of (III) adopt an overall V shape. There are no intermolecular amine–nitro hydrogen bonds. Rather, each amine H atom has a long (H...O ca 2.8 Å) interaction with one of the sulfone O atoms. Molecules of (III) are thus linked by amine–sulfone N—H...O hydrogen bonds into zigzag double chains running along [001]. Taken together, these structures demonstrate that small changes in the functionalization of ethylamine–nitroarenes cause significant differences in the intermolecular interactions and packing.     

Hydro­gen bonds and C—H⋯O ­interactions in the enol tautomer of 4‐­(phenylsulfonyl)spiro­[cyclo­pentane‐1,9′‐[9H]­fluorene]‐2,3‐dione

The title compound, 2‐hydroxy‐1‐(phenyl­sulfonyl)­spiro­[cyclo­pentene‐4,9′‐[9H]­fluoren]‐3‐one, C₂₃H₁₆O₄S, crystallized in the centrosymmetric space group P2₁/n with one mol­ecule as the asymmetric unit. The hydroxyl‐H atom is ordered and participates in a single intramolecular hydrogen bond and in a single intermolecular hydrogen bond, in which the O_D—H distance is 0.90 (2), H?O_A is 2.34 (3), O_D?O_A is 2.987 (2) Å and O_D—H?O_A is 129 (2)°. The intermolecular hydrogen bond forms an R(12) cyclic dimer about a center of symmetry. There are six leading C—H?O interactions. Taken together, these interactions form a three‐dimensional network. Structural comparisons are made with tetrabenzodi­spiro­[4.0.4.3]­tridecatetraene.     

N1‐(4‐tert‐Butyl­phenyl)‐N2‐hydroxy‐α‐oxo‐α‐phenyl­acet­amidine and N2‐hydroxy‐N1‐(4‐nitro­phenyl)‐α‐oxo‐α‐phenyl­acet­amidine hemihydrate

In the title compounds, C₁₈H₂₀N₂O₂, (I), and C₁₄H₁₁N₃O₄·0.5H₂O, (II), respectively, the oxime groups have an E configuration. In (I), the mol­ecules exist as polymers bound by intermolecular C—H⋯O and O—H⋯N hydrogen bonds around inversion centres. In (II), intermolecular OW—H⋯N, OW—H⋯O and O—H⋯OW interactions stabilize the molecular packing.     

2‐Iodo‐N‐(3‐nitrobenzyl)aniline and 3‐iodo‐N‐(3‐nitrobenzyl)aniline exhibit entirely different patterns of supramolecular aggregation

In 2‐iodo‐N‐(3‐nitro­benzyl)­aniline, C₁₃H₁₁IN₂O₂, the mol­ecules are linked into a three‐dimensional structure by a combination of C—H?O hydrogen bonds, iodo–nitro interactions and aromatic π–π‐stacking interactions, but N—H?O and C—H?π(arene) hydrogen bonds are absent. In the isomeric 3‐iodo‐N‐(3‐nitro­benzyl)­aniline, a two‐dimensional array is generated by a combination of N—H?O, C—H?O and C—H?π(arene) hydrogen bonds, but iodo–nitro interactions and aromatic π–π‐stacking interactions are both absent.     

The ternary complex 4‐(2‐pyridyl)pyridinium–3,5‐di­nitro­benzoate–3,5‐di­nitro­benzoic acid (1/1/1)

In the title ternary complex, C₁₀H₉N₂⁺·C₇H₃N₂O₆^?·C₇H₄N₂O₆, the pyridinium cation adopts the role of the donor in an intermolecular N—H?O hydrogen‐bonding interaction with the carboxyl­ate group of the 3,5‐di­nitro­benzoate anion. The mol­ecules of the ternary complex form molecular ribbons perpendicular to the b direction, which are stabilized by one N—H?O, one O—H?O and five C—H?O intermolecular hydrogen bonds. The ribbons are further interconnected by three intermolecular C—H?O hydrogen bonds into a three‐dimensional network.     

Similarities and differences in the structures of 5‐bromo‐6‐hydroxy‐7,8‐dimethylchroman‐2‐one and 6‐hydroxy‐7,8‐dimethyl‐5‐nitrochroman‐2‐one

The title compounds, C₁₁H₁₁BrO₃, (I), and C₁₁H₁₁NO₅, (II), respectively, are derivatives of 6‐hydroxy‐5,7,8‐trimethylchroman‐2‐one substituted at the 5‐position by a Br atom in (I) and by a nitro group in (II). The pyranone rings in both molecules adopt half‐chair conformations, and intramolecular O—H...Br [in (I)] and O—H...O_nitro [in (II)] hydrogen bonds affect the dispositions of the hydroxy groups. Classical intermolecular O—H...O hydrogen bonds are found in both molecules but play quite dissimilar roles in the crystal structures. In (I), O—H...O hydrogen bonds form zigzag C(9) chains of molecules along the a axis. Because of the tetragonal symmetry, similar chains also form along b. In (II), however, similar contacts involving an O atom of the nitro group form inversion dimers and generate R₂²(12) rings. These also result in a close intermolecular O...O contact of 2.686 (4) Å. For (I), four additional C—H...O hydrogen bonds combine with π–π stacking interactions between the benzene rings to build an extensive three‐dimensional network with molecules stacked along the c axis. The packing in (II) is much simpler and centres on the inversion dimers formed through O—H...O contacts. These dimers are stacked through additional C—H...O hydrogen bonds, and further weak C—H...O interactions generate a three‐dimensional network of dimer stacks.     

Intermolecular O—H⃛O hydrogen bonding in the three independent molecules of (2S)‐3‐(4‐hydroxyphenyl)‐2‐(1‐oxoisoindolin‐2‐yl)­propanoic acid

The title compound, C₁₇H₁₅NO₄, derived from l ‐tyrosine, crystallizes with three independent mol­ecules which differ in the conformation of the asymmetric unit: the N—C—C—C_ipso torsion angles are ?71.7 (5), ?63.6 (6) and ?52.5 (5)°, respectively. Deformations in the phenol ring hydroxy O—C—C angles of 116.5 (4)/123.9 (4), 121.7 (5)/118.1 (4) and 122.4 (5)/118.6 (5)°, respectively, result from their respective intermolecular hydrogen‐bonding environments. Intermolecular O_acid—H?O=C_indole, O_phenol—H?O—H_phenol and O_phenol—H?O=C_indole hydrogen bonds, with O?O distances in the range 2.607 (4)–2.809 (4) Å, are present in combination with C—H?O and C—H?π_arene interactions. The primary hydrogen‐bonding systems assemble with graph sets R₃³(8) and R₃²(22).     

2,2,2‐Trinitroethanol

2,2,2‐Trinitroethanol, C₂H₃N₃O₇, at 100 (2) K has Z′ = 2 in the space group P2₁/c. The structure displays intramolecular O—H...O hydrogen bonds, as well as intermolecular O—H...O and C—H...O hydrogen bonding; the O—H...O hydrogen bonds, forming R₄⁴(8) rings, and dipolar nitro–nitro interactions account for the high density of 1.839 Mg m⁻³.     

Hydro­gen bonds and C—H⃛O interactions in N‐(2‐hydroxy‐1,1‐dimethyl­ethyl)benzamide at 150 K

The title compound, C₁₁H₁₅NO₂, crystallized in the centrosymmetric space group P2₁/n with one mol­ecule in the asymmetric unit. There is a single intermolecular hydrogen bond, in which the N_donor?O_acceptor distance is 3.0374 (11) Å and the N—H?O angle is 171.0 (12)°. The single intramol­ecular hydrogen bond has an O_donor?O_acceptor distance of 2.6279 (11) Å and an O—H?O angle of 161.8 (14)°. The four leading intermolecular C—H?O interactions have H?O distances ranging from 2.52 to 2.65 (2) Å and C—H?O angles ranging from 125.2 (9) to 143°. Chains of interactions form two‐dimensional networks.     

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.     

Substituent position effect on the crystal structures of N‐phenyl‐2‐phthalimidoethanesulfonamide derivatives

In order to determine the impact of different substituents and their positions on intermolecular interactions and ultimately on the crystal packing, unsubstituted N‐phenyl‐2‐phthalimidoethanesulfonamide, C₁₆H₁₄N₂O₄S, (I), and the N‐(4‐nitrophenyl)‐, C₁₆H₁₃N₃O₆S, (II), N‐(4‐methoxyphenyl)‐, C₁₆H₁₆N₃O₆S, (III), and N‐(2‐ethylphenyl)‐, as the monohydrate, C₁₈H₁₈N₂O₄S·H₂O, (IV), derivatives have been characterized by single‐crystal X‐ray crystallography. Sulfonamides (I) and (II) have triclinic crystal systems, while (III) and (IV) are monoclinic. Although the molecules differ from each other only with respect to small substituents and their positions, they crystallized in different space groups as a result of differing intra‐ and intermolecular hydrogen‐bond interactions. The structures of (I), (II) and (III) are stabilized by intermolecular N—H…O and C—H…O hydrogen bonds, while that of (IV) is stabilized by intermolecular O—H…O and C—H…O hydrogen bonds. All four structures are of interest with respect to their biological activities and have been studied as part of a program to develop anticonvulsant drugs for the treatment of epilepsy.     

Hydrogen‐bonded networks in 1‐(4‐methoxyphenyl)‐2,2‐dimethylpropan‐1‐ol

The asymmetric unit of the title compound, C₁₂H₁₈O₂, contains two independent molecules. They differ only slightly in conformation but form completely different intermolecular hydrogen‐bonded arrays. One molecule exhibits disorder in the hydroxy group region, but this does not influence the formation of hydrogen bonds. The bulky tert‐butyl group on one side of the carbinol C atom and the benzene ring on the other side promote the formation of discrete dimeric motifs via hydrogen‐bridged hydroxy groups. Dimers are further joined by strong hydroxy–methoxy O—H...O bonds to form chains with dangling alcohol groups. Weaker intermolecular C—H...O interactions mediate the formation of a two‐dimensional network.