2-Picolinium tetrachloridoaurate(III), (C6H8N)[AuCl4] or (2-PicH)[AuCl4], 1, and 2-picolinium tetrabromidoaurate(III), (C6H8N)[AuBr4] or (2-PicH)[AuBr4], 2, both crystallize in the space group P1 with Z = 4, but are not isotypic. Bis(2-picolinium) tetrabromidoaurate(III) bromide, (C6H8N)2[AuBr4]Br or (2-PicH)2[AuBr4]Br, 3, crystallizes in the space group P1 with Z = 2. All atoms of 1–3 lie on general positions. 3-Picolinium tetrabromidoaurate(III), (C6H8N)[AuCl4] or (3-PicH)[AuBr4], 4, crystallizes in the space group P21/c with Z = 4; the two independent anions each display inversion symmetry. trans-Dibromidobis(4-picoline)gold(III) tetrabromidoaurate(III) nitromethane monosolvate, [AuBr2(C6H7N)2](AuBr4]·CH3NO2 or [(4-Pic)2AuBr2](AuBr4]·CH3NO2, 5, and 4-picolinium tetrabromidoaurate(III), (C6H8N)[AuBr4] or (4-PicH)[AuBr4], 6, both crystallize in the space group P1 with Z = 2; both involve two independent anions with inversion symmetry. 2,4-Lutidinium tetrabromidoaurate(III), (C7H10N)[AuBr4] or (2,4-LutH)[AuBr4], 7, crystallizes in the space group P212121 with Z = 4. All the gold(III) species show the expected square-planar geometry. The main interest centres on the packing patterns. In 1, hydrogen bonds, Cl...Cl contacts, axial Au...Cl contacts (‘coinage bonds’) and Cl...π contacts combine to form layers parallel to (101). In 2, similar contacts (but involving Br) link the residues to form corrugated layers parallel to the ac plane. In 3, classical hydrogen bonds, Br...Br contacts and a coinage bond, all involving the free bromide ion, combine to produce rings of composition Au2Br4, which are then linked by another Br...Br contact, to form chains of residues parallel to [011]. In 4, hydrogen bonds and a Br...Br contact generate chains of residues parallel to [101], which are in turn linked by a Br...π contact. In 5, Br...Br contacts and coinage bonds link the anions and cations to form a corrugated layer structure parallel to the ac plane, involving six-membered Au2Br4 and ten-membered Au4Br6 rings. A similar combination of contacts in 6 leads to a layer structure parallel to the ab plane, also involving a pattern of six- and ten-membered rings topologically analogous to that of 5. However, the angles in the rings of the two layers differ appreciably, and 6 also contains a short Br...π contact. In 7, a hydrogen bond combines with a coinage bond to produce a ribbon of residues parallel to the a axis. Three further, longer and perhaps borderline, Br...Br and Br...Cg contacts link the ribbons to form a three-dimensional pattern.

Trichlorido(4-methylpiperidine)gold(III), [AuCl3(C6H13N)], 1, crystallizes in Pbca with Z = 8. Tribromido(4-methylpiperidine)gold(III), [AuBr3(C6H13N)], 2, crystallizes as two polymorphs, 2a in Pnma with Z = 4 (imposed mirror symmetry) and 2b, which is isotypic to 1. The Au—N bonds trans to Cl are somewhat shorter than those trans to Br, and the Au—Cl bonds trans to N are longer than those cis to N, whereas the Au—Br bonds trans to N are slightly shorter than the cis bonds. The methyl and AuX 3 groups (X = halogen) occupy equatorial positions at the six-membered ring. The packing of all three structures involves chains of molecules with offset stacking of the AuX 3 moieties associated with short Au...X contacts; for 1 and 2b these are reinforced by N—H...X hydrogen bonds, whereas for 2a there are no classical hydrogen bonds and the chains are interconnected by Br...Br contacts.

In bis(4-methylpiperidine-κN)gold(I) chloride, [Au(C6H13N)2]Cl (1), the methyl groups are, as expected, equatorial at the piperidine ring, but the Au atom is axial; this is the case for all five structures reported here, as is the expected linear coordination at the Au atom. Hydrogen bonding of the form N—H...Cl−...H—N leads to inversion-symmetric dimers, which are further connected by C—H...Au contacts. Bis(4-methylpiperidine-κN)gold(I) dichloridoaurate(I), [Au(C6H13N)2][AuCl2] (2), also forms inversion-symmetric dimers; these involve aurophilic interactions and three-centre hydrogen bonds of the form NH(...Cl)2. Bis(4-methylpiperidine-κN)gold(I) dibromidoaurate(I), [Au(C6H13N)2][AuBr2] (3), is isotypic to 2. The 1:1 adduct chlorido(4-methylpiperidine-κN)gold(I) bis(4-methylpiperidine-κN)gold(I) chloride, [Au(C6H13N)2]Cl·[AuCl(C6H13N)] (4), crystallizes as its dichloromethane solvate. The asymmetric unit contains two formula units, in each of which the chloride anion accepts a hydrogen bond from the cation and from the neutral molecule, and the two Au atoms are linked via an aurophilic interaction. A further hydrogen bond leads to inversion-symmetric dimers. The asymmetric unit of bis(2-methylpiperidine-κN)gold(I) chloride, [Au(C6H13N)2]Cl (5), contains two `half' cations, in which the Au atoms lie on twofold axes, and a chloride ion on a general position. Within each cation, the relative configurations at the atoms N and C2 (which bears the methyl substituent) are R,S. The twofold-symmetric dimer involves two N—H...Cl−...H—N units and an aurophilic contact between the two Au atoms.

All three structures involve chains of mol­ecules linked by Au⋯halogen contacts; these are accompanied by hydrogen bonds or halogen⋯halogen contacts.

Tri-chlorido-(4-methyl-piperidine)-gold(III), [AuCl3(C6H13N)], 1, crystallizes in Pbca with Z = 8. Tri-bromido-(4-methyl-piperidine)-gold(III), [AuBr3(C6H13N)], 2, crystallizes as two polymorphs, 2a in Pnma with Z = 4 (imposed mirror symmetry) and 2b, which is isotypic to 1. The Au-N bonds trans to Cl are somewhat shorter than those trans to Br, and the Au-Cl bonds trans to N are longer than those cis to N, whereas the Au-Br bonds trans to N are slightly shorter than the cis bonds. The methyl and AuX 3 groups (X = halogen) occupy equatorial positions at the six-membered ring. The packing of all three structures involves chains of mol-ecules with offset stacking of the AuX 3 moieties associated with short Au⋯X contacts; for 1 and 2b these are reinforced by N-H⋯X hydrogen bonds, whereas for 2a there are no classical hydrogen bonds and the chains are inter-connected by Br⋯Br contacts.

Bis(2-methylpyridine)gold(I) dibromidoaurate(I), [Au(C6H7N)2][AuBr2], (1), crystallizes in space group C2/c with Z = 4. Both gold atoms lie on twofold axes and are connected by an aurophilic contact. A second aurophilic contact leads to infinite chains of alternating cations and anions parallel to the b axis, and the residues are further connected by a short H...Au contact and a borderline Br...Br contact. Bis(3-methylpyridine)gold(I) dibromidoaurate(I), [Au(C6H7N)2][AuBr2], (2), crystallizes in space group C2/m with Z = 2. Both gold atoms lie on special positions with symmetry 2/m and are connected by an aurophilic contact; all other atoms except for one methyl hydrogen lie in mirror planes. The extended structure is closely analogous to that of 1, although the structures are formally not isotypic. Bis(3,5-dimethylpyridine)gold(I) dichloridoaurate(I), [Au(C7H9N)2][AuCl2], (3) crystallizes in space group P\overline{1} with Z = 2. The cation lies on a general position, and there are two independent anions in which the gold atoms lie on inversion centres. The cation and one anion associate via three short H...Cl contacts to form a ribbon structure parallel to the b axis; aurophilic contacts link adjacent ribbons. Bis(3,5-dimethylpyridine)gold(I) dibromidoaurate(I), [Au(C7H9N)2][AuBr2], (4) is isotypic to 3. Attempts to make similar compounds involving 2-bromopyridine led instead to 2-bromopyridinium dibromidoaurate(I)–2-bromopyridine (1/1), (C5H5BrN)[AuBr2]·C5H4BrN, (5), which crystallizes in space group P\overline{1} with Z = 2; all atoms lie on general positions. The 2-bromopyridinium cation is linked to the 2-bromopyridine molecule by an N—H...N hydrogen bond. Two formula units aggregate to form inversion-symmetric dimers involving Br...Br, Au...Br and H...Br contacts.

The structures of seven gold(III) halide derivatives of general formula LAuX 3 (L = methylpyridines or dimethylpyridines, X = Cl or Br) are presented: trichlorido(2-methylpyridine)gold(III), [AuCl3(C6H7N)], 1 (as two polymorphs 1a and 1b); tribromido(2-methylpyridine)gold(III), [AuBr3(C6H7N)], 2; tribromido(3-methylpyridine)gold(III), [AuBr3(C6H7N)], 3; tribromido(2,4-dimethylpyridine)gold(III), [AuBr3(C7H9N)], 4; trichlorido(3,5-dimethylpyridine)gold(III), [AuCl3(C7H9N)], 5; tribromido(3,5-dimethylpyridine)gold(III), [AuBr3(C7H9N)], 6, and trichlorido(2,6-dimethylpyridine)gold(III), [AuCl3(C7H9N)], 7. Additionally, the structure of 8, the 1:1 adduct of 2 and 6, [AuBr3(C6H7N)]·[AuBr3(C7H9N)], is included. All the structures crystallize solvent-free, and all have Z′ = 1 except for 5 and 7, which display crystallographic twofold rotation symmetry, and 4, which has Z′ = 2. 1a and 2 are isotypic. The coordination geometry at the gold(III) atoms is, as expected, square-planar. Four of the crystals (1a, 1b, 2 and 8) were non-merohedral twins, and these structures were refined using the ‘HKLF 5’ method. The largest interplanar angles between the pyridine ring and the coordination plane are observed for those structures with a 2-methyl substituent of the pyridine ring. The Au—N bonds are consistently longer trans to Br (average 2.059 Å) than trans to Cl (average 2.036 Å). In the crystal packing, a frequent feature is the offset-stacked and approximately rectangular dimeric moiety (Au—X)2, with antiparallel Au—X bonds linked by Au...X contacts at the vacant positions axial to the coordination plane. The dimers are connected by further secondary interactions (Au...X or X...X contacts, `weak' C—H...X hydrogen bonds) to form chain, double chain (`ladder') or layer structures, and in several cases linked again in the third dimension. Only 1b and 7 contain no offset dimers; these structures instead involve C—H...Cl hydrogen bonds combined with Cl...Cl contacts (1b) or Cl...π contacts (7). The packing patterns of seven further complexes LAuX 3 involving simple pyridines (taken from the Cambridge Structural Database) are compared with those of 1–8.

In bromido(pyrrolidine-κN)gold(I) bis(pyrrolidine-κN)gold(I) bromide, [AuBr(pyr)]·[Au(pyr)2]Br (pyr = pyrrolidine, C4H9N), 2, alternating [AuBr(pyr)] molecules and [Au(pyr)2]+ cations are connected by aurophilic contacts to form infinite chains of residues parallel to the b axis. The chains are cross-linked by three N—H...Br− hydrogen bonds and an Au...Br contact to form a layer structure parallel to the ab plane. Trichlorido(piperidine-κN)gold(III), [AuCl3(pip)] (pip = piperidine, C5H11N), 3, consists of molecules with the expected square-planar coordination at the gold atom, which are connected by an N—H...Cl hydrogen bond and an Au...Cl contact to form a layer structure parallel to the ac plane. The structures of bis(piperidinium) tetrachloridoaurate(III) chloride, (pipH)2[AuCl4]Cl, 4, and bis(pyrrolidinium) tetrabromidoaurate(III) bromide, (pyrH)2[AuBr4]Br, 6, are closely related but not isotypic. Compound 6 crystallizes in space group Ibam; the Au and two Br atoms of the anion lie in the mirror plane x, y, 0, whereas the bromide ions occupy special positions 0, 0.5, 0 and 0, 0.5, 0.25, with site symmetry 2/m. The NH2 group forms a hydrogen bond to one bromide ion, and also a three-centre hydrogen bond to the other bromide atom and to a metal-bonded Br atom. The packing involves chains of hydrogen-bonded pyrrolidinium and bromide ions parallel to the c axis, combined with a layer structure of [AuBr4]− and bromide anions, parallel to the ab plane and involving Au...Br and Br...Br contacts. Compound 4, however, crystallizes pseudosymmetrically in space group Iba2; two chlorine atoms of the anion lie on the twofold axis 0.5, 0.5, z, and there are two independent cations. The packing is closely similar to that of 6, but there are no N—H...Cl hydrogen bonds to metal-bonded chlorines. The contact distances Au...Cl are appreciably longer than their Au...Br counterparts in 6, whereas the Cl...Cl contact is much shorter than Br...Br in 6. Tribromido(piperidine-κN)gold(III) crystallizes as its dichloromethane solvate, [AuBr3(pip)]·CH2Cl2, 7. It too displays a square-planar coordination at the gold atom. The packing involves hydrogen bonds N—H...Br, stacking of neighbouring AuBr3 units by Au...Br contacts, and a short Br...Br contact; these combine to form a layer structure parallel to the ac plane.

The compounds bis(morpholine-κN)gold(I) chloride, [Au(C4H9NO)2]Cl, 1, and bis(morpholine-κN)gold(I) bromide, [Au(C4H9NO)2]Br, 2, crystallize isotypically in space group C2/c with Z = 4. The gold atoms, which are axially positioned at the morpholine rings, lie on inversion centres (so that the N—Au—N coordination is exactly linear) and the halide anions on twofold axes. The residues are connected by a classical hydrogen bond N—H...halide and by a short gold...halide contact to form a layer structure parallel to the bc plane. The morpholine oxygen atom is not involved in classical hydrogen bonding.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Abstract The reaction of (tht)AuCl (tht=tetrahydrothiophene) with KSCN leads to a mixture of gold(I) thiocyanate AuSCN and [(tht)2Au]+ [Au(SCN)2]− 1. The compounds were separated and the X-ray structure of 1 confirmed as an alternating chain of anions and cations linked by aurophilic contacts. Either pure AuSCN or the mixture was used to synthesize further derivatives of AuSCN, all of which were investigated by X-ray methods. Most products were of limited stability when removed from their mother liquor. The dimethyl sulfide derivative 2 is molecular, (Me2S)AuSCN; the ammonia derivative 3 is ionic, [(NH3)2Au]+ [Au(SCN)2]−. The reaction with 2,2-bipyridyl leads (presumably by involvement of the solvent or of atmospheric moisture) to [bipy-H]+ [Au(SCN)2]− 13. All other products involve amines or azaaromatics as ligands L. The primary amine tert-butylamine forms an ionic product [L2Au]+ (SCN)− 4. The secondary amines piperidine and dibenzylamine lead to molecular structures LAuSCN (5 and 6), whereas pyridine-based azaaromatics lead to ionic products [L2Au]+ [Au(SCN)2]− with L=2-, 3- or 4-picoline (7–9), 2,4-, 3,4- or 3,5-lutidine (10–12). The 3,4-lutidine derivative 11 forms two polymorphs that tend to form mixed crystals. The dominant features of the crystal packing for 7–12 are short aurophilic interactions.

Reactions between potassium tetraiodidoaurate(III) and pyridine (py, C5H5N) or 3,4-lutidine (3,4-dimethylpyridine, 3,4-lut, C7H9N) were tested as possible sources of azaaromatic complexes of gold(III) iodide, but all identifiable products contained gold(I). The previously known structure dipyridinegold(I) diiodidoaurate(I), [Au(py)2]+·[AuI2]-, (3) [Adams et al. (1982). Z. Anorg. Allg. Chem. 485, 81-91], was redetermined at 100 K. The reactions with 3,4-lutidine gave three different types of crystal in small quantities. 3,4-Dimethylpyridine-3,4-dimethylpyridinium diiodidoaurate(I), [(3,4-lut)2H]+·[AuI2]-, (1), consists of an [AuI2]- anion on a general position and two [(3,4-lut)2H]+ cations across twofold axes. Bis(3,4-dimethylpyridine-3,4-dimethylpyridinium) diiodidoaurate(I) iodide, [(3,4-lut)2H+]2·[AuI2]-·I-, (2), crystallizes as two polymorphs, each forming pseudosymmetric inversion twins, in the space groups P21 and Pc (but resembling P21/m and P2/c), respectively. These are essentially identical layer structures differing only in their stacking patterns and thus might be regarded as polytypes.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Abstract The reaction of (tht)AuX (X=Cl or Br; tht=tetrahydrothiophene) with various primary amines L leads to products of the form [L2Au]+X−. Packing diagrams of the corresponding structures are dominated by N–H···X hydrogen bonds and (in some cases) aurophilic contacts. The cyclohexylamine derivative was already known as its dichloromethane ⅔-solvate; we have isolated the solvent-free compound and its pentane ¼-solvate, which all show different packing patterns. With acyclic secondary amines, the products are more varied; LAuX and [L2Au]+[AuX2]− were also found. These gold(I) products were generally formed in satisfactory quantities. The attempted oxidation to Au(III) derivatives with PhICl2 or Br2 proved impossible for the primary amine derivatives [although isopropylamine-trichloridogold(III) was obtained unexpectedly from the corresponding cyanide] and unsatisfactory for the secondary amine derivatives. Products LAuX3 and [L2AuX2]+[AuX4]− were identified but were formed in disappointing yields. In isolated cases protonated products (LH)+[AuCl4]−, (LH+)3[AuCl4]−(Cl−)2 or [(Et2N)2CH]+[AuBr4]− were formed, presumably by involvement of the dichloromethane solvent and/or adventitious water. Here also the yields were poor, and some products arose as mixtures. Direct reaction of amines with AuCl3 or (tht)AuX3 was also unsuccessful. All products were characterized by X-ray structure analysis.

Abstract The first methylamine complexes of gold are reported. Both crystallize in chiral trigonal space groups. In bis(methylamine)gold(I) chloride [(CH3NH2)2Au]+ Cl−, the gold and chlorine atoms lie on twofold axes in space group P3121. The packing is largely determined by two hydrogen bonds of the form N–H···Cl, which combine to form chains of rings, the latter with graph set R 4 2 ( 12 ) . ${\rm{R}}_4^2(12).$ Aurophilic interactions are at best borderline [Au···Au 3.9014(2) Å]. Cyano(methylamine)gold(I), (CH3NH2)AuCN crystallizes in space group P31; the molecules are connected by short aurophilic contacts [Au···Au 3.1507(2) Å] to form spiral chains parallel to the c axis, and also by two hydrogen bonds of the form N–H···N≡C.

Abstract Silver cyanide can be treated with liquid amines or azaaromatics L to give crystalline complexes of various compositions, among them complexes of the simple type cyanido(amine)silver(I): L=isobutylamine and 4-picoline. Other AgCN:L ratios obtained were: 1:2 (benzylamine and 4-benzylpiperidine), 2:1 (2,4-lutidine), 2:3 (morpholine and 3,4-lutidine) and 3:4 (3,5-lutidine). The packing diagrams were analyzed in terms of Ag–Ag and Ag–CN contacts and N–H···N hydrogen bonds. The contacts often give rise to chains, which are sometimes linked to layers by hydrogen bonds.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

In the title compound, 2C5H12N+·SO42-·2C3H8N2S, the C=S groups of the two independent 1,3-di-methyl-urea mol-ecules and the sulfur atom of the anion lie on twofold axes. The packing is centred on bis-(piperidinium) sulfate ribbons parallel to the c axis; the cations are hydrogen bonded to the sulfate by N-H⋯O and C-H⋯O inter-actions. The 1,3-di-methyl-urea mol-ecules are also hydrogen bonded to sulfate O atoms, and project outwards from the ribbon parallel to the b axis.

The structure of the 2,2'-bipyridyl adduct poly[(μ2-2,2'-bipyridyl-κ3N,N':N)di-μ3-cyanido-κ6C:N:N-gold(I)potassium(I)], [AuK(CN)2(C10H8N2)]n, (1) (space group P21), has been redetermined [previous determination: Jones et al. (1980). Acta Cryst. B36, 160-162]. The bipyridyl ligands coordinate only the potassium ion, which has a coordination sphere consisting of seven N-atom donors; gold(I) remains in the form of linear dicyanidoaurate(I) ions. The extended structure consists of layers in which the AuI atoms form chains parallel to the short a axis, with Au...Au contacts of 3.7286 (1) Å, whereas the chains of potassium ions, which are also parallel to a, are bridged by bipyridyl and dicyanidoaurate residues. The analogous 1,10-phenanthroline adduct, namely poly[di-μ3-cyanido-κ6C:N:N-(μ2-1,10-phenanthroline-κ3N,N':N)gold(I)potassium(I)], [AuK(CN)2(C12H8N2)]n, (2), crystallizes as nonmerohedral twins in the space group C2/c. The packing is closely related to that of (1), but the chains are now parallel to the short b axis and the layers are parallel to (10\overline{1}). The two independent AuI atoms occupy special positions on inversion centres and twofold axes; the Au...Au contacts are 3.6771 (2) Å.