Synthesis and X-ray structure analysis of 2-acetylamino-benzoic acid

The title compound crystallizes in the orthorhombic space group Fdd2 with unit cell parameters a = 10.848(1) Å, b = 30.264(1) Å and c = 10.577(1) Å, V = 3472.47(2) ų, and Z = 4. The final reliability index is 0.030 for 700 observed reflections. Nitrogen of the amide group and carbon atom of the acid group deviate significantly below and above the plane of the phenyl ring. The crystal cohesion is accentuated by N—HO and O—HO hydrogen bonds.     

Crystal structure of the piperazine-1,4-diium (DL-)hydrogen malate (1:2)

The crystalline salt of piperazine-1,4-diium (DL-)hydrogen malate (1:2), (C₄H₁₂N₂)²⁺ (C₄H₅O₅)₂^–, has been prepared and characterized by X-ray crystallography. The title salt crystallizes in monoclinic space group P2₁/n with a = 7.073(1), b = 14.180(2), c = 7.526(1) Å, = 94.66(1), V = 752.33(18) ų and Z = 2. Results indicate that the title salt exists as a racemic compound but a conglomerate. In the structure, axial and equatorial hydrogen atoms of piperiaine-1,4-diium are all involved in different bifurcated hydrogen bonds. The integral structure, formed by the hard hydrogen bonds of N–HsO and O–HsO, is stabilized further by soft hydrogen bond of C–HsO.     

The crystal structure of 5-amino-2-nitrobenzoic acid

The crystal structure of 5-amino-2-nitrobenzoic acid (5A2NB) was determined by the X-ray diffraction method. The 5-amino-2-nitrobenzoic acid crystallizes in the monoclinic P2₁/c space group with a = 3.898(2) Å, b = 13.531(3) Å, c = 14.301(3) Å, and = 90.83(3)°. The adjacent molecules form a cyclic dimmer by intermolecular hydrogen bonds of type O—HsO with their carboxyl groups. In the crystal structure NH₂ group forms a three-center hydrogen bond with oxygen atoms of NO₂ group. The IR spectrum and thermal properties of acid are discussed.     

Crystal structures of two substituted key intermediates of phenothiazine derivatives

The key intermediates, in the synthesis of phenothiazines, 5-hydroxy-5-methyl 3(phenyl) 2,4-N-dimethylcarbamoyl cyclohexanone, C₁₇H₂₂O₄N₂ (I), and 5-hydroxy-5-methyl 3(2-methylphenyl) 2,4-N-dimethylcarbamoyl cyclohexanone, C₁₈H₂₄O₄N₂ (II), contain essentially substituted cyclohexanone rings in chair conformation with approximately perpendicular oriented phenyl rings. The carbamoyl groups are aligned in opposite directions to facilitate the formation of intramolecular C–HO interaction and O–HO hydrogen bonding. The molecules are linked in helical fashion by an N–HO type intermolecular hydrogen bonding framework. Crystal data: [I], orthorhombic, space group Pbca, a = 9.278(1), b = 19.094(2), c = 19.802(2) Å, V = 3508.0(6) ų, Z = 8 and d = 1.206 Mg m^–3, R = 0.074 (wR = 0.137) for 208 parameters and 1190 observed reflections with I 2 (I); [II], monoclinic, space group P2₁/n, a = 10.523(1), b = 9.005(1), c = 19.771(2) Å, = 94.96(6)°, V = 1866.5(3) ų, Z = 4 and d = 1.183 Mg m^–3, R = 0.062 (wR = 0.131) for 217 parameters and 2276 observed reflections with I 2 (I).     

Synthesis and crystal structure of Bi(mpo)3 (Hmpo = 2-mercaptopyridine N-oxide)

The synthesis as well as crystal and molecular structure of [Bi(C₅H₄NOS)₃] are reported. The complex crystallizes in the monoclinic system, space group P2₁/n with lattice parameters a = 9.6521(3) Å, b = 10.0659(4) Å, c = 18.4484(7) Å, = 102.13(6)°, and D _calc = 2.227 Mg · m^–3 for Z = 4. It is clear from the packing diagram that the title compound is a dimer via the secondary coordination. Surrounding Bi atom, three five-membered ring planes (Bi,O,N,C,S) make a dihedral angle of 55.91, 54.72, and 26.13° respectively. The whole crystal presents a three-dimensional network structure as each molecule produces four weak C–H O hydrogen bonds and a weak C–H S hydrogen bond.     

Rotational disorder in 1,5-dihydroxy xanthone

The crystal structure of 1,5-dihydroxy xanthone obtained from Callophyllum trapezifolium has been determined (C₁₃H₈O₄), Mr = 228.21, a = 5.547(5), b = 5.186(5), c = 16.487(5) Å, = 91.40(1), Z = 2 and V = 474.1(6) ų. The xanthone molecule is planar and exhibits rotational disorder in the crystal. The packing of the molecules in the crystal lattice is due to inter- and intramolecular O–H O hydrogen bonds forming infinite chains.     

Crystal structure of di(N-benzyl piperidinium) pentachloroantimonate(III) dihydrate

The salt di(N-benzyl piperidinium) pentachloroantimonate(III) dihydrate crystallizes in the orthorhombic system with space group Cmc2₁, the unit cell dimensions are: a = 29.383(1), b = 10.509(2), c = 9.941(1) Å, with Z = 8. The structure shows a layer arrangement perpendicular to the a axis: planes of SbCl₆ octahedra alternate with planes of [C₁₂H₁₇N]⁺ cations. The SbCl₆ octahedra are connected through a O(W)–HCl hydrogen bonds and a chlorine bridge, so that infinite unidimensional chains of composition [SbCl₅(H₂O)₂]^2n– _n are formed in the structure along the c direction. These chains are connected to [C₁₂H₁₇N]⁺ entities by N–HCl and N–HO(W) hydrogen bonds, forming a three-dimensional network. It was found that lengths of Sb–Cl bonds may differ from each other. The differences shown as a distortion of the SbCl₆ octahedra were attributed to the Sb(III) lone electron pair stereoactivity.     

Synthesis and crystal structure of a new two-dimensional chromium(III) network through hydrogen bonds

A new chromium(III) complex, [Cr(ox)(bdmpza)(H₂O)], (ox = oxalate dianion and bdmpza = bis(3,5-dimethylpyrazol-1-yl)acetate, respectively), has been synthesized and characterized by X-ray crystallography. This compound crystallizes in the monoclinic space group P2₁/c, with a = 7.008(3) Å, b = 14.229(5) Å, c = 16.497(7) Å, = 101.588(7)°, V = 1611.5(11) ų, Z = 4. The chromium atom has a distorted octahedral environment with different coordination atoms. Bis(3,5-dimethylpyrazol-1-yl)acetate anion is a tridentate ligand, and the oxalate group acts as a chelating bidentate ligand. This compound also forms an infinite two-dimensional network through O–H O hydrogen bonds. The lengths of the hydrogen bonds are 2.765(5) and 2.733(5) Å, respectively.     

2-[(trifluoroacetyl)amino]benzoquinone and the hydrochloride and perchlorate salts of 2-aminohydroquinone

Hydrogen bonding parameters for the title materials are reported. 2-[(trifluoroacetyl)amino]benzoquinone crystallizes in the monoclinic space group P2 ₁/c, with a = 18.195(4), b = 5.110(1), c = 9.635(2), = 104.22(3)°, V = 868.4(3) ų, and Z = 4. This compound exhibits two weak intramolecular hydrogen bonds. The first is between a hydrogen atom of the quinone ring and the carbonyl oxygen of the trifluoroacetamide group; it has a distance of 2.24 Å and a C—HsO angle of 122°. The second is between the hydrogen atom of the trifluoroacetamide group and a quinone carbonyl group; it has a distance of 2.26 Å and a N—HsO angle of 107°. 2-Aminohydroquinone hydrochloride crystallizes in the orthorhombic space group Pca2₁, with a = 16.220(3), b = 5.211(1), c = 8.719(2), V = 737.0(2) ų, and Z = 4. 2-Aminohydroquinone perchlorate crystallizes in the orthorhombic space group P2₁2₁2₁, with a = 7.110(1), b = 7.139(1), c = 18.043(4), V = 915.8(3) ų, and Z = 4. All active hydrogens of the two salts exhibit intermolecular hydrogen bonds that serve to organize a three-dimensional framework for each case.     

Crystal and molecular structure of [Cu2(3,5-dihydroxybenzoate)4 (acetonitrile)2] ⋅ 8H2O

The crystal and molecular structure of the title compound, [Cu₂(3,5-dihydroxybenzoate)₄ (acetonitrile)₂] 8H₂O 1, is reported. Crystal data for 1: tetragonal, space group I 4/m, a = 11.720(2) Å, c = 15.304(3) Å, V = 2102.4(6), and D _c = 1.53 g/cm³, for Z = 2. The metal and organic components crystallize to form a Cu paddle-wheel complex, of idealized D_4h symmetry, that assembles in the solid-state, along with eight equivalents of water, to form a 3D hydrogen-bonded network held together by O–H O hydrogens bonds. The metal complexes pack to form a 2D layered structure.     

Crystal structure and characterization of 1,2-N,N-disallicydene-phenylamineato nickel(II) complex

A new complex has been synthesized and characterized by elemental analysis, IR, TGA, and single-crystal X-ray analysis. The crystal is orthorhombic and the space group is chiral (P2₁2₁2₁) with a = 6.620(3) Å, b = 17.300(4) Å,, c = 5.450(1) Å,, = 90°, = 90°, = 90°, z = 4. In the crystal lattice, the molecules create a two-dimensional network structure through hydrogen bonds. The C–HO intermolecular hydrogen bonds connect the title complex to form a supermolecular structure.     

Structural characterization of Elisabatin B and Elisabatin C

X-ray structures of Elisabatin B (1) and Elisabatin C (2) have been determined. Crystal data for 1: Triclinic, P (No. 2), a = 7.528(2) Å, b = 9.404(2) Å, c = 11.414(2) Å, = 75.363(3)°, = 86.668(4)°, = 89.683(4)°, and Z = 2. Crystal data for 2: Monoclinic, P2₁/c (No. 14), a = 8.242(2) Å, b = 14.870(2) Å, c = 13.060(2) Å, = 101.458(3)°, and Z = 4. Both compounds are highly unsaturated leading to extended aromatic conjugation. They show different intermolecular O–HO hydrogen bonds, via which 1 forms dimers, and 2 zig-zag polymeric chains.     

Hydrogen-bond networks in the mono- and diprotonated cyclic diamine [9]aneN2S

The hydrogen-bond networks in the mono- and diprotonated cyclic diamine, 1-thia-4,7-diazacyclononane, [9]aneN₂S, have been examined. Crystals of the monoprotonated, form [9]aneN₂S HCl, contain a ribbon-like network of alternating strong and weak intermolecular N H Cl hydrogen bonds and weak intramolecular N H N hydrogen bonds. Crystal data for [9]aneN₂S HCl: monoclinic, a = 6.6640(6) Å, b = 10.3493(9) Å, c = 6.9807(6) Å, = 108.847(1)°, V = 455.63(7) ų, space group P2₁, Z = 2. In the di-protonated form, [9]aneN₂S 2HBr, the ribbon-like network comprises strong intermolecular and weak intramolecular N H Br hydrogen bonds. Crystal data for [9]aneN₂S 2HBr: orthorhombic, a = 12.5918(13) Å, b = 8.0753(9) Å, c = 10.6856(11) Å, V = 1086.5(2) ų, space group Pnma, Z = 4. The chloride anions of [9]aneN₂S HCl align in interlocking columns in the a- and c-direction whereas the bromide anions in [9]aneN₂S 2HBr occupy channels in the b-direction.     

A comparison of the crystal structures of (dabcoH2)CuCl4 and (dabcoH2)CuCl4⋅H2O

The crystal structures of the anhydrous and monohydrated (dabcoH₂)CuCl₄nH₂O salts (n = 0,1) have been determined and a comparison of their crystal structures has been reported. The anhydrous salt is monoclinic P2₁/c with a = 9.045(2) Å, b = 6.9270(10) Å, c = 18.767(4) Å and = 90.07(3)° with V = 1175.8(4) ų. The hydrated salt is also monoclinic P2₁/c with a = 9.266(2) Å, b = 9.395(2) Å, c = 14.386(3) Å and = 93.32(3)° with V = 1250.3(5) ų. The structures of the two salts are closely related. Both compounds contain isolated distorted (compressed) tetrahedral CuCl₄ ^2– anions, diprotonated dabco cations, and in the case of the hydrated salt, lattice H₂O molecules. In the anhydrous salt, each of the two N–H⁺ groups of the dabcoH₂ ²⁺ dications form bifurcated hydrogen bonds to chloride ions on adjacent CuCl₄ ^2– anions along the c axis, thus forming chains running parallel to the c axis. In the hydrated salt, a water molecule is inserted into one of the pair of bifurcated hydrogen bonds, forming instead N–H O–H CuCl₄ ^2– linkages. The chains thus formed are cross-linked by O–H Cl hydrogen bonds between the chains. Because of this additional hydrogen bonding, the CuCl₄ ^2– anions in the hydrated salt are distorted further from tetrahedral geometry.     

Synthesis and structure of [(nitrito-O,O′) bis(di-2-pyridylamine)copper(II)] nitrite

The synthesis and molecular structure of the title compound, [(nitrito-O,O) (dpa)₂Cu(II)] (NO₂), 1, is reported. Compound 1 crystallized in the orthorhombic space group Pccn with a = 11.397(5) Å, b = 12.256(6) Å, c = 14.876(8) Å, and V = 2077.9(17) ų with Z = 4. The distorted octahedral copper(II) cations are linked through a hydrogen-bonded polymer network. The polymer network is formed through the amine N–H of the cations and hydrogen bonded to the N–HO nitrite anions.     

Hydrogen bonding in labdane diterpenoids, labda-7,12(E),14-triene-17-oic acid and labda-12(Z),14,17-triene-18-oic acid

Two labdane diterpenoids, labda-7,12(E),14-triene-17-oic acid (1) and labda-12(Z),14,17-triene-18-oic acid (2), C₂₀H₃₀O₂, have been isolated from Croton oblongifolius. Both 1 and 2 crystallized in the monoclinic system, space group C2, with cell dimensions of a = 21.912(1) Å, b = 7.4002(4) Å, c = 11.5079(7) Å, = 101.999(1)^o and a = 21.308(2) Å, b = 11.9067(9) Å, c = 7.5606(6) Å, = 100.763(1)^o, respectively. Compound 1, a rare example of carboxylic group bound to a cyclohexene ring, forms an infinite intermolecular hydrogen-bonded polymer [O1 O2(–x + 1/2, y + 1/2, –z + 2) 2.697(2) Å], whereas molecules of compound 2 are linked to form an asymmetric hydrogen-bonded dimer [O1 O2(–x, y, –z) 2.657(3) Å].     

Crystal structures and vibrational spectra of racemic and chiral 4-phenyl-1,3-oxazolidine-2-thione

The crystal structures of (rac)- and (R)-4-phenyl-1,3-oxazolidine-2-thione (4-POT) have been determined by X-ray diffraction. The structure of (rac)-4-POT is monoclinic P2₁/n with a = 11.9096(9) Å, b = 5.9523(6) Å, c = 12.3563(8) Å, = 91.054(6)°, V = 875.8(1) ų, and Z = 4. The structure of (R)-4-POT is orthorhombic P2₁2₁2₁ with a = 7.7197(6) Å, b = 21.603(2) Å, c = 5.4613(9) Å, V = 910.8(2) ų, and Z = 4. (rac)-4-POT and (R)-4-POT crystals are shown to have different hydrogen-bonding patterns. In the racemic crystals, the enantiomeric (R)- and (S)-4-POT molecules are connected to form a cyclic dimer via the N–H S hydrogen bond of the cis thioamide moiety [N Sⁱ 3.438(2) Å, N–H Sⁱ 176(2)° symmetry code: (i) 1 – x, 1 – y, 1 – z]. In the chiral (R)-4-POT crystals, the N–H S intermolecular hydrogen bond forms a zigzag chain around the twofold screw axis [N Sⁱⁱ 3.347(3) Å, N–H Sⁱⁱ 161(3)° symmetry code: (ii) 1/2 + x, 1/2 – y, 2 – z]. Observed difference of 46°C in the melting points between the (rac)-4-POT and (R)-4-POT crystals is correlated with difference in the crystal packing. Vibrational spectra of (rac)- and (R)-4-POT crystals are discussed both in the solid state and in solution.     

Structure, thermal behavior, and IR investigations of (C6H9N2)H2PO4

Chemical preparation, X-ray single-crystal, thermal behavior, and IR spectroscopy studies of a new dihydrogenmonophosphate associated to an organic cation, the 3-(ammoniummethyl)pyridine dihydrogenmonophosphate (denoted as AMPP) are described. The AMPP crystallizes in the monoclinic system with P2₁/c space group. The unit cell dimensions are a = 5.8465(2) Å, b = 19.9776(9) Å, c = 7.3103(3) Å, = 90.848(3)° with V = 853.74(4) ų and Z = 4. The structure has been solved using direct method and refined to a reliability R factor of 0.0393. The structure of AMPP includes three types of hydrogen bonds. The first one, O H O, links the H₂PO₄ groups to form infinite inorganic chains [H₂PO₄]n ^n–, parallel to the c axis. The two other types, O H N and N H O assemble inorganic chains so as to build up a three-dimensional arrangement.     

Synthesis and structural properties of a 1-D copper(I) coordination polymer

A coordination polymer catena-chloro(4-pyridinecarboxylic acid)copper(I): [Cu(C₆H₅ O₂N)Cl]_n (1) has been prepared directly by reacting Cu^IICl₂ 2H₂O and 4-cyanopyridine in the presence of disodium maleate under hydrothermal conditions at 140°C. Crystal data for 1 are as follows: monoclinic, P2₁/n, a = 16.4623(9) Å, b = 3.7795(2) Å, c = 24.7612(11) Å, = 101.534(1)°, V = 1509.5(1) ų, Z = 4, D _calc. = 1.955 g cm^–3, R1 = 0.0511, wR2 = 0.1060 for all 2666 reflections. In this 1-D stair-polymer, two [Cu–Cl–Cu]_n zigzag chains are held together by weak interchain Cu–Cl bonds. The 4-pyridinecarboxylic acid ligands derived from the 4-CNpy molecules coordinate to the approximately tetrahedral Cu(I) centers through pyridyl-N atoms. The carboxyl ends of 4-pyridinecarboxylic acid participate in interchain hydrogen-bonding interactions to form a 2-D supramolecular network.     

Synthesis and X-ray crystallography of cholest-3,5-diene-7-one-oxime

Cholest-3,5-diene-7-one-oxime (C₂₇H₄₃NO) was prepared using a usual synthetic route and its three-dimensional structure was determined by X-ray diffraction methods. The transparent platelike crystals of this compound crystallized in the monoclinic space group P2₁, with unit cell parameters a = 14.302(2) Å, b = 11.475(2) Å, c = 15.919(4) Å, = 106.04(1)°, (Cu K) = 1.5418 Å, Z = 4. The structure was solved by direct methods and refined to an R-value of 0.075 for 4640 observed reflections. Two crystallographically independent molecules were observed in the asymmetric unit cell. The ring A in both the molecules was found to exist in 1,10 half-chair conformation while ring C in chair conformation. The rings B and D in both the molecules adopted different conformations. Three intermolecular interactions of the type C–H O and C–H N were also observed.