In the title mol-ecule, C15H22O2, there is an intra-molecular hydrogen bond involving the hy-droxy and aldehyde groups and forming an S(6) ring. The mean plane of the non-H atoms of this ring [(H)O-C C-C=O, with a maximum deviation of 0.013 (1) Å] are essentially coplanar with the benzene ring, forming a dihedral angle of 2.29 (8)°.
In the title salt (common name l-carnitine hydro-chloride), C(7)H(16)NO(3) (+)·Cl(-), the organic cation features a carb-oxy-lic part (-CO(2)H) having unambigous single- and double-bonds [1.336 (2), 1.211 (2) Å]. There is a large N-C-C bond angle [115.9 (1)°] for the C atom connected to the bulky trimethyl-amino substituent. In the crystal, the acid H atom forms a hydrogen bond to the chloride anion, whereas the hydroxyl H atom forms a longer hydrogen bond to the anion, generating a helical chain running along [001].
In the title ammonium polyoxometallate salt, (C(6)H(16)N)(4)[H(2)V(10)O(28)], the anion features O atoms engaged in μ(6)-, μ(3)- and μ(2)-bridging of adjacent V(V) atoms, confering an octa-hedral coordination at each of the twenty unique metal atoms. Two anions are linked by μ(3)- and μ(2)-bridged OH units across a center of inversion, forming a dimer which is linked to the cations by N-H⋯O hydrogen bonds. The cation is disordered over two positions in a 0.776 (4):0.224 (4) ratio in one of the two independent ion pairs in the asymmetric unit, and 0.627 (10):0.373 (10) in the other.
The unit cell of the title compound, C(7)H(6)O(4)·H(2)O, features four independent formula units; the individual carb-oxy-lic acid mol-ecules themselves are nearly planar (r.m.s. deviations = 0.0189, 0.0334, 0.0356 and 0.0441 Å). Two independent mol-ecules each form two hydrogen bonds by acid-carbonyl O-H⋯O inter-actions and the dimers are also nearly planar (r.m.s. deviations = 0.039 and 0.049 Å). The two independent dimers are aligned at 44.5 (1)°. Other O-H⋯O inter-actions involving the hy-droxy groups and water mol-ecules give rise to a three-dimensional network.
The Sn(IV) atom in the centrosymmetric dinuclear title compound, [Sn(2)(C(4)H(9))(4)(C(7)H(3)NO(4))(2)(H(2)O)(2)], exists in a trans-C(2)SnNO(4) penta-gonal-bipyramidal geometry. There are two half-mol-ecules in the asymmetric unit that are completed by inversion symmetry. The crystal studied was a non-merohedral twin with a ratio of 47.3 (1)% for the minor twin component. Bond dimensions are similar to those found in the tetra-gonal polymorph [Huber et al. (1989 ▶). Acta Cryst. C45, 51-54]. O-H⋯O hydrogen-bonding interactions stabilize the crystal packing.
The K atom in the title complex, [K(C(10)H(6)NO(2))(C(10)H(7)NO(2))(3)], lies on a twofold rotation axis that relates one N,O-chelating quinoline-2-carb-oxy-lic acid to the other; their N and O atoms are cis to each other in the distorted octa-hedral coordination geometry. The K atom is also coordinated by another monodentate quinoline-2-carb-oxy-lic acid; the acid is disordered with respect to a monodentate quinoline-2-carboxyl-ate anion; the acid and anion are linked by an O-H⋯O hydrogen bond. An O-H⋯N hydrogen bond links adjacent mol-ecules into a linear chain structure along the a axis.
The Sn(IV) atom in the title compound, [Sn(C(4)H(9))(2)Cl(2)(C(12)H(8)N(2))], is chelated by the N-heterocycle; the n-butyl groups are trans to each other whereas the Cl atoms are cis to each other. The crystal studied was a non-merohedral twin with the minor domain being in a 15.8 (1)% proportion.
The non-H atoms of the title compound, C(5)H(3)ClN(2)O(2), almost lie in a common plane (r.m.s. deviation = 0.090 Å). In the crystal, adjacent mol-ecules feature a short Cl⋯O contact [3.068 (4) Å], forming a chain; these chains are consolidated into a layer structure by non-classical C-H⋯O inter-actions.
The non-H atoms of the title compound, C(6)H(8)N(2), lie in a common plane (r.m.s. deviation = 0.034 Å). In the crystal, adjacent mol-ecules are linked by inter-molecular N-H⋯N hydrogen bonds into a zigzag chain running along the c axis.
The aromatic ring of the title compound, C(6)H(3)ClN(2)O(5), is almost planar (r.m.s. deviation = 0.007 Å); one nitro substituent is nearly coplanar with the ring [dihedral angle = 3(1)°], whereas the other is twisted [dihedral angle = 36 (1)°]. The phenol OH group is intra-molecularly hydrogen bonded to the nitro group that is coplanar with the ring, generating an S(6) graph-set motif.
In the title salt, C(7)H(11)N(2) (+)·Br(3) (-), the essentially planar cation (r.m.s. deviation = 0.006 Å) forms an N-H⋯Br hydrogen bond to one of the Br atoms of the almost linear anion [Br-Br-Br = 179.31 (2)°]. The crystal studied was found to be a racemic twin. The whole-mol-ecule disorder of the cation and anion about a twofold rotation axis described earlier [Ng (2009). Acta Cryst. E65, o1276] is an artifact of halving one of the axes of the ortho-rhom-bic unit cell.
In the title compound, C(5)H(3)ClN(2)O(2), the nitro group is twisted by 38.5 (2)° with respect to the pyridine ring. In the crystal, adjacent mol-ecules are linked by non-classical C-H⋯N and C-H⋯O hydrogen bonds, forming a layer motif.
The asymmetric unit of the title organotin(IV) compound, [Sn(C(4)H(9))(2)(C(5)H(3)N(2)O(2))(2)(H(2)O)], contains one-and-a-half mol-ecules. The half-mol-ecule is completed by crystallographic twofold symmetry, with its Sn and water O atoms lying on the rotation axis. Both mol-ecules feature seven-coordinate Sn atoms in trans-C(2)SnN(2)O(3) penta-gonal-bipyramidal coordination environments. The carboxyl-ate anions N,O-chelate to the Sn atom. In the crystal, the carboxyl-ate O atoms not involved in coordination serve as acceptors for O-H⋯O hydrogen bonds from adjacent water mol-ecules, generating a three-dimensional network.
In the centrosymmetric title compound, C(18)H(12)N(2)S(24), the five- (r.m.s. deviation = 0.002 Å) and six-membered (r.m.s. deviation = 0.002 Å) rings are essentially coplanar [dihedral angle between rings = 1.9 (1)°].
The title compound, 2C(8)H(13)N(2) (+)·2Cl(-)·C(8)H(12)N(2)·H(2)O, is a hydrated 2:1 cocrystal of the 2-amino-4,5-dimethyl-anilinium chloride salt and the 4,5-dimethyl-benz-ene-1,2-diamine free base. An intra-molecular N-H⋯N hydrogen bond occurs in one of the organic mol-ecules. In the crystal structure, the components are linked by N-H⋯Cl, N-H⋯N, N-H⋯O and O-H⋯Cl hydrogen bonds into a layered motif.
The asymmetric unit of the title double salt, (C(5)H(6)N)(3)[FeBr(4)](2)Br, consists of three pyridinium cations, two tetra-hedral bromidoferrate(III) anions and a bromide anion. The three cations each form one N-H⋯Br hydrogen bond to the bromide anion. The crystal under investigation was a non-merohedral twin, with a portion of 22% for the minor twin component.
Compared to the previous studies [Ng (1997 ▶). Acta Cryst. C53, 56-58; Yin et al. (2005 ▶). Huaxue Shiji, 27, 295-296], the redetermined structure of the title compound, [Sn(C(7)H(7))(3)Cl], exhibits a doubled c unit-cell parameter. There are two mol-ecules in the asymmetric unit, with both Sn and both Cl atoms having 3 site symmetry. The Sn atoms have distorted SnClC(3) tetra-hedral geometries and the mol-ecules inter-act by way of short Sn⋯Cl bridges [Sn⋯Cl = 3.418 (2) and 3.475 (2) Å], thereby forming chains propagating in c.
In the title compound, C(8)H(5)ClN(2), the planar mol-ecules are arranged with their Cl atoms in close contact [Cl⋯Cl = 3.808 (1) and 3.881 (1) Å], indicating weak Cl⋯Cl inter-actions, which give rise to a supra-molecular chain.
In the crystal structure of the title salt, K(3)[Pb(CH(3)COO)(2)(NCS)](NCS)(2), the [Pb(CH(3)COO)(2)(NCS)](-) anion exists as a covalently bonded entity in which the acetate anions chelate in an anisobidentate manner. The Pb atom shows a distorted ψ-octa-hedral coordination to four acetate O atoms and one isocyanate N atom, with the stereochemically active lone pair occupying one of the six sites. When the three longer Pb⋯S inter-actions are considered, the eight-coordinate geometry is based on a dodeca-hedron. The Pb(CH(3)COO)(2)(NCS)](-) anion has mirror symmetry. The potassium cations connect the other constituents into a three-dimensional network through electrostatic K⋯N and K⋯S inter-actions.
The mol-ecule of the title compound, C(9)H(5)Cl(2)NO, is essentially planar [give maximum or r.m.s. deviation] and the hydr-oxy group acts as a hydrogen-bond donor to the N atom of a symmetry-related mol-ecule, generating a hydrogen-bonded dimer,which lies on a twofold rotation axis.