The title hydrated quinoline derivative, C(11)H(9)NO(3)·2H(2)O, crystallizes as a zwitterion in which the quinoline N atom is protonated. The quinoline ring is essentially planar, with a maximum deviation of 0.017 (2) Å. An intra-molecular N-H⋯O hydrogen bond between the protonated N atom and the O atom of the carboxyl-ate group in the zwitterion forms an S(5) ring motif. In the crystal, the zwitterions are connected into inversion dimers via pairs of N-H⋯O and C-H⋯O hydrogen bonds with R(2) (2)(4) and R(1) (2)(6) motifs. The water mol-ecules are connected via O-H⋯O hydrogen bonds, forming supra-molecular chains along the c axis. Furthermore, the chains and the dimers are connected via O-H⋯O hydrogen bonds, forming ladder-like supra-molecular ribbons along the c axis.
In the title salt, C(6)H(9)N(2) (+)·C(4)H(3)O(4) (-), the dihedral angle between the pyridine ring and the plane formed by the hydrogen fumarate anion is 85.67 (6)°. Excluding the amino and methyl groups, the atoms of the cation are coplanar, with a maximum deviation of 0.005 (1) Å. In the crystal structure, the protonated N atom and the 2-amino group of the cation are hydrogen bonded to the carboxyl-ate O atoms of the anion via a pair of N-H⋯O hydrogen bonds, forming an R(2) (2)(8) ring motif. These motifs are further connected through N-H⋯O and C-H⋯O hydrogen bonds, leading to a supra-molecular chain along the c axis. These chains are further cross-linked via a pair of O-H⋯O hydrogen bonds involving centrosymmetrically related hydrogen fumarate anions, forming a two-dimensional network parallel to (101). These planes are further interconnected by O-H⋯O interactions into a three-dimensional network.
In the title salt, C(5)H(6)BrN(2) (+)·C(5)H(7)O(4) (-), the 2-amino-5-bromo-pyridinium cation is essentially planar, with a maximum deviation of 0.005 (3) Å. In the crystal structure, the proton-ated N atom and the 2-amino group of the cation are hydrogen bonded to the carboxyl-ate O atoms of the anion via a pair of N-H⋯O hydrogen bonds, forming an R(2) (2)(8) ring motif. The ion pairs are further connected via O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds, forming a two-dimensional network parallel to the bc plane. In the network, the hydrogen glutarate (4-carb-oxy-butano-ate) anions self-assemble through O-H⋯O hydrogen bonds, forming a supra-molecular chain along the c axis.
In the crystal structure of the title salt, 2C(6)H(9)N(2) (+)·C(8)H(4)O(4) (2-)·4H(2)O, the terephthalate carboxyl-ate groups inter-acts with the 2-amino-4-methyl-pyridinium cations via a pair of N-H⋯O hydrogen bonds, forming an R(2) (2)(8) ring motif. The water mol-ecules form an R(6) (6)(12) ring motif through O-H⋯O hydrogen bonds and these motifs are fused, forming a supra-molecular chain along the c axis. The R(2) (2)(8) and R(6) (6)(12) ring motifs are connected via O-H⋯O hydrogen bonds. In addition, π-π stacking inter-actions are observed between the pyridinium rings [centroid-centroid distance = 3.522 (12) Å].
In the title salt, C(5)H(6)ClN(2) (+)·C(6)H(4)NO(3) (-)·0.85H(2)O, the pyridin-ium ring is planar, with a maximum deviation of 0.010 (2) Å. In the crystal structure, the cations, anions and water mol-ecules are linked via N-H⋯O, O-H⋯O and C-H⋯O hydrogen bonds, forming a three-dimensional network.
The asymmetric unit of the title salt, C(5)H(6)BrN(2) (+)·C(7)H(5)O(6)S(-), contains two independent 2-amino-5-bromo-pyridinium cations and two independent 3-carb-oxy-4-hy-droxy-benzene-sulfonate anions. The hy-droxy and carboxyl groups of the anions are involved in intra-molecular O-H⋯O hydrogen bonds, which generate S(6) ring motifs. In the crystal structure, the ions are linked by N-H⋯O and O-H⋯O hydrogen bonds into a two-dimensional network parallel to (110). Adjacent networks are linked via C-H⋯O hydrogen bonds.
The mol-ecular structure of the title compound, C(8)H(12)N(2)O, indicates that 2-isopropyl-6-methyl-pyrimidin-4-ol (the enol-form) undergoes an enol-to-keto tautomerism during the crystallization process. The pyrimidin-4(3H)-one group is essentially planar, with a maximum deviation of 0.081 (1) Å for the O atom. In the crystal structure, symmetry-related mol-ecules are linked into centrosymmetic dimers via pairs of inter-molecular N-H⋯O hydrogen bonds, generating R(2) (2)(8) rings. These dimers are stacked along the a axis.
In the title salt, C(6)H(9)N(2) (+)·C(6)H(7)O(2) (-)·2H(2)O, the non-H atoms of the 2-amino-4-methyl-pyridinium cation are coplanar, with a maximum deviation of 0.010 (1) Å. In the crystal structure, the pyridinium N atom and the 2-amino group of the cation are hydrogen bonded to the carboxyl-ate O atoms of the anion via a pair of N-H⋯O hydrogen bonds, forming an R(2) (2)(8) ring motif. The sorbate anions and water mol-ecules are linked through O-H⋯O hydrogen bonds, forming R(10) (10)(28) and R(6) (4)(12) ring motifs. The motifs form part of a three-dimensional framework.
In the title compound, C(7)H(11)N(2)O(2)S(+)·Cl(-), the 4,6-dimeth-oxy-2-(methyl-sulfan-yl)pyrimidinium cation is essentially planar (r.m.s. deviation = 0.043 Å). In the crystal, the anions and cations are connected by inter-molecular N-H⋯Cl and C-H⋯Cl hydrogen bonds, forming a two-dimensional network parallel to (011). Adjacent networks are cross-linked via π-π inter-actions involving the pyrimidinium ring [centroid-centroid distance = 3.5501 (8) Å].
The asymmetric unit of the title compound, C(5)H(9)N(3) (2+)·2Cl(-), contains two diprotonated 2,3-diamino-pyridine cations and four chloride anions. In the crystal structure, the anions and cations are connected by inter-molecular N-H⋯Cl and C-H⋯Cl hydrogen bonds, forming a three-dimensional network. The crystal structure is further stabilized by π-π inter-actions between pyridinium rings [centroid-centroid distance = 3.695 (1) Å].
In the title salt, C(6)H(9)N(2) (+)·C(7)H(4)NO(4) (-), the nitro group of the 4-nitro-benzoate anion is twisted by 7.66 (10)° from the attached ring. In the crystal structure, the 2-amino-4-methyl-pyridinium cations and 4-nitro-benzoate anions are linked via a pair of N-H⋯O hydrogen bonds to form a ribbon-like structure along the c axis. The ribbons are crosslinked into a three-dimensional framework by C-H⋯O hydrogen bonds.
In the title compound, C(5)H(8)N(3) (+)·C(7)H(5)O(2) (-)·C(7)H(6)O(2), the carboxyl and carboxyl-ate groups are twisted away from their attached benzene rings by 10.75 (7) and 20.33 (6)°, respectively. In the crystal structure, the 2,3-diamino-pyridinium cations, benzoate anions and benzoic acid mol-ecules are linked into a two-dimensional network parallel to (001) by O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds and π-π inter-actions between the pyridinium rings [centroid-centroid distance = 3.4981 (7) Å].
In the title compound, C(5)H(5)ClN(2)·C(7)H(6)O(2), the carboxyl group of the benzoic acid mol-ecule is twisted away from the attached ring by 14.22 (7)°. In the crystal, the 2-amino-5-chloro-pyridine mol-ecules inter-act with the carboxyl groups of benzoic acid mol-ecules through N-H⋯O and O-H⋯N hydrogen bonds, forming cyclic R(2) (2)(8) hydrogen-bonded motifs, and linking the mol-ecules into chains parallel to the [001] direction. Neighbouring 2-amino-5-chloro-pyridine mol-ecules are also centrosymmetrically paired through C-H⋯Cl hydrogen bonds, forming another R(2) (2)(8) motif. The crystal structure is further stabilized by weak C-H⋯O hydrogen bonds.
In the title mol-ecular salt, C(8)H(13)N(2)O(+)·C(7)H(3)N(2)O(7) (-)·H(2)O, the pyrimidinium cation is essentially planar, with a maximum deviation of 0.009 (1) Å. The cation undergoes an enol-keto tautomerism during the crystallization. In the crystal, the ion pairs and water mol-ecules are connected via O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds, forming two-dimensional networks parallel to the bc plane. There is an intra-molecular O-H⋯O hydrogen bond in the 3,5-dinitro-salicylate anion, which generates an S(6) ring motif.
In the title salt, C(5)H(8)N(3) (+)·C(7)H(3)N(2)O(7) (-), the pyridine N atom of the 3,4-diamino-pyridine mol-ecule is protonated. The 3,5-dinitro-salicylate anion shows whole-mol-ecule disorder over two orientations with a refined occupancy ratio of 0.875 (4): 0.125 (4). In the crystal, the cations and anions are connected by inter-molecular N-H⋯O and C-H⋯O hydrogen bonds, forming a three-dimensional network.
In the title salt, C(6)H(9)N(2) (+)·C(7)H(5)O(3) (-), the carboxyl-ate mean plane of the 4-hydroxy-benzoate anion is twisted by 13.07 (4)° from the attached ring. In the crystal structure, the ions are linked into a two-dimensional network by N-H⋯O, O-H⋯O and C-H⋯O hydrogen bonds. Within this network, the N-H⋯O hydrogen bonds generate R(2) (2)(8) ring motifs. In addition, π-π inter-actions involving the pyridinium rings, with a centroid-centroid distance of 3.7599 (4) Å, are observed.
The asymmetric unit of the title compound, 3C(5)H(6)ClN(2) (+)·3C(8)H(5)O(4) (-)·C(8)H(6)O(4), contains three independent 2-amino-5-chloro-pyridinium cations, three independent hydrogen phthal-ate anions and one phthalic acid mol-ecule. In the crystal structure, there are two kinds of supra-molecular tapes. One is formed by two independent cations with two anions through N-H⋯O and C-H⋯O hydrogen bonds. Another one is formed by the other cation and anion, and the phthalic acid mol-ecule via N-H⋯O, O-H⋯O and C-H⋯O hydrogen bonds. These two tapes are connected by an O-H⋯O hydrogen bond, forming a double-tape structure.
In the title salt, C(6)H(9)N(2) (+)·C(7)H(4)ClO(2) (-), the 2-amino-4-methyl-pyridinium cation is almost planar, with a maximum deviation of 0.010 (1) Å. In the crystal, the protonated N atom and the 2-amino group of the cation are hydrogen bonded to the carboxyl-ate O atoms of the anion via a pair of N-H⋯O hydrogen bonds, forming an R(2) (2)(8) ring motif. The ion pairs are further connected via N-H⋯O and C-H⋯O hydrogen bonds, forming a two-dimensional network parallel to the bc plane.
In the title salt, C(6)H(9)N(2) (+)·C(5)H(7)O(4) (-), the 2-amino-5-methyl-pyridinium cation is essentially planar, with a maximum deviation of 0.008 (1) Å. In the crystal, the protonated N atom and the 2-amino group are hydrogen bonded to the carboxyl-ate O atoms via a pair of N-H⋯O hydrogen bonds, forming an R(2) (2)(8) ring motif. The 4-carb-oxy-butano-ate anions are linked via O-H⋯O hydrogen bonds. The crystal structure is further stabilized by weak C-H⋯O inter-actions.
In the title compound, C(5)H(6)BrN(2) (+)·C(2)F(3)O(2) (-), the F atoms of the anion are disordered over two sets of sites, with occupancies of 0.59 (2):0.41 (2). In the crystal structure, the anions and cations are linked into a two-dimensional network parallel to (100) by N-H⋯O and C-H⋯O hydrogen bonds. Within this network, the N-H⋯O hydrogen bonds generate R(2) (2)(8) ring motifs.