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In the crystal structure of Na2SeO3·5H2O [disodium selenate(IV) pentahydrate], two Se, two selenite O atoms and one water O atom are located on a mirror plane, and one water O atom is located on a twofold rotation axis. The coordination of one Na+ cation is distorted trigonal bipyramidal, formed by three equatorial H2O ligands and two axial selenite O atoms. The other Na+ cation has an octahedral coordination by six water molecules. The two independent SeO3 groups form almost undistorted trigonal pyramids, with Se—O bond lengths in the range 1.6856 (7)–1.7202 (10) Å and O—Se—O angles in the range 101.98 (3)–103.11 (5)°, and both are μ2-O:O-bonded to a pair of Na+ cations. Hydrogen bonds involving all water molecules and selenite O atoms consolidate the crystal packing. Although anhydrous Na2SeO3 and Na2TeO3 are isotypic, the title compound is surprisingly not isotypic with Na2TeO3·5H2O. In the tellurite hydrate, all Na+ cations have an octahedral coordination and the TeO3 groups are bonded to Na+ only via one of their three O atoms. more...

The crystal structure of tamarugite [sodium aluminium bis(sulfate) hexahydrate] was redetermined from a single crystal from Mina Alcaparossa, near Cerritos Bayos, southwest of Calama, Chile. In contrast to the previous work [Robinson & Fang (1969). Am. Mineral. 54, 19–30], all non-H atoms were refined with anisotropic displacement parameters and H-atoms were located by difference Fourier methods and refined from X-ray diffraction data. The structure is built up from nearly regular [Al(H2O)6]3+ octahedra and infinite double-stranded chains [Na(SO4)2]3− that extend parallel to [001]. The Na+ cation has a strongly distorted octahedral coordination by sulfate O atoms [Na—O = 2.2709 (11) – 2.5117 (12) Å], of which five are furnished by the chain-building sulfate group S2O4 and one by the non-bridging sulfate group S1O4. The [Na(SO4)2]3− chain features an unusual centrosymmetric group formed by two NaO6 octahedra and two S2O4 tetrahedra sharing five adjacent edges, one between two NaO6 octahedra and two each between the resulting double octahedron and two S2O4 tetrahedra. These groups are then linked into a double-stranded chain via corner-sharing between NaO6 octahedra and S2O4 tetrahedra. The S1O4 group, attached to Na in the terminal position, completes the chains. The [Al(H2O)6]3+ octahedron (〈Al—O〉 = 1.885 (11) Å) donates 12 comparatively strong hydrogen bonds (O...O = 2.6665 (14) – 2.7971 (15) Å) to the sulfate O atoms of three neighbouring [Na(SO4)2]3− chains, helping to connect them in three dimensions, but with a prevalence parallel to (010), the cleavage plane of the mineral. Compared with the previous work on tamarugite, the bond precision of Al—O bond lengths as an example improved from 0.024 to 0.001 Å. more...

In the title compound, [Ir(C15H22BN6)(C8H7O)Cl]·CHCl3, the Ir atom is formally trivalent and is coordinated in a slightly distorted octahedral geometry by three facial N atoms, one C atom, one O atom and one Cl atom. The Ir=Ccarbene bond is strong and short and exerts a notable effect on the trans-Ir—N bond, which is about 0.10 Å longer than the two other Ir—N bonds. The chloroform solvent molecule is anchored via a weak C—H...Cl hydrogen bond to the Cl atom of the Ir complex molecule. In the crystal, the constituents adopt a layer-like arrangement parallel to (010) and are held together by weak intermolecular C—H...Cl hydrogen bonds, as well as weak Cl...Cl [3.498 (2) Å] and Cl...π [3.360 (4) Å] interactions. A weak intramolecular C—H...O hydrogen bond is also observed. more...

The molecular structure of the title compound, C20H18N2O5S·C3H7NO, represents an essentially planar 5-benzylidene-thiazolidine moiety (r.m.s. deviation from planarity without ring substituents = 0.095 Å) to which the 4-aminobenzoic acid fragment is inclined at 76.23 (1)°. In the crystal, the benzoic acid molecules are arranged in layers parallel to [001] which are built up from inversion dimers held together by head-to-tail phenol–carboxy O—H...O hydrogen bonds and head-to-tail π–π stacking interactions between the 5-benzylidene-thiazolidine moieties (ring centroid distance = 3.579 Å). These layers are separated by the dimethylformamide solvent molecules which are firmly anchored via a short O—H...O hydrogen bond [O...O = 2.5529 (10) Å] donated by the –COOH group. more...

The crystal structure of the title compound, C15H14N4, contains chains of coplanar tetrazole rings with the chain direction along b. These are formed through weak hydrogen bonds, donated by the tetrazole H atoms and by one of the H atoms of the methylene group, and accepted by two neighbouring N atoms of the adjacent tetrazole ring. The chains are connected to each other in a staircase-like manner via weak hydrogen bonds, donated from the second H atom of the methylene group and accepted by the N atom next to the C atom in the tetrazole ring. The resulting layers are parallel to the bc plane. more...

The title compound, C11H20N2PS+·BF4−, is a salt of 2-(diisopropylthiophosphorylamino)pyridine, a chelating bidentate ligand that furnishes an S atom as a soft donor and a pyridine N atom as a hard atom for transition-metal complexation. The title salt crystallizes with two formula units in the asymmetric unit. The two independent cations are protonated at the pyridine N atoms and have the S atoms syn-oriented to them so as to form bent intramolecular N—H...S hydrogen bonds, one of which one is bifurcated by involving also an N—H...F interaction. The phosphorylamino NH groups form near linear hydrogen bonds to proximal tetrafluoroborate anions. Five weak C—H...F and three weak C—H...S interactions link the constituents into a three-dimensional framework. As a result of the crystal packing, the two cations differ notably in conformation, as can be seen from the S—P—N—C torsion angles of −18.7 (1)° in the first and −35.1 (1)° in the second cation. more...

The title compound, C34H52N2O7·CH4O, is the methanol solvate of a difunctionalized derivative of the therapeutic agent 18β-glycyrrhetinic acid, a pentacyclic triterpene. The five six-membered rings of the glycyrrhetinic acid moiety show normal geometries, with four rings in chair conformations and the unsaturated ring in a half-chair conformation. This moiety is substituted by a nitrate ester group and an O-ethylglycine group. In the crystal, the nonsolvent molecules are packed parallel to (010) in a herringbone fashion with the nitrato, ethylglycine and methanol-O atom being proximate. The methanol solvent molecule is anchored via a donated O—H...Oacyl and an accepted N—H...O hydrogen bond, giving rise to infinite zigzag chains of hydrogen bonds parallel to [100]. Two weak intermolecular C—H...O interactions to the methanol and to an acyl oxygen establish links along [100] and [010], respectively. more...

In the title compound, [Fe(CH3CN)3(C29H27N5OP2)](BF4)2·2CH3CN, the FeII ion is octahedrally coordinated by a meridionally chelating tridentate pincer-type PNP ligand derived from 2,6-diamino-4-ethoxy-1,3,5-triazine and by three acetonitrile molecules. The four Fe—N bond lengths range from 1.9142 (12) to 1.9579 (11) Å, while the Fe—P bonds are 2.2452 (4) and 2.2506 (4) Å [P—Fe—P = 165.523 (14)°], consistent with FeII in a low-spin state. Unlike related Fe PNP complexes based on 2,6-diaminopyridine, the BF4 anions are not hydrogen bonded to the two NH groups of the pincer ligand but show instead anion–π interactions with the triazine ring and acetonitrile molecules in addition to ten C—H...F interactions. Most remarkable among these is an anion–π(triazine) interaction with a short distance of 2.788 (2) Å between one F and the centroid of the π-acidic triazine ring. The corresponding shortest distance between this F atom and a triazine carbon atom is 2.750 (2) Å. The two NH groups of the pincer ligand donate N—H...N hydrogen bonds to the triazine N atom of a neighbouring complex and to an uncoordinated acetonitrile molecule. This last molecule is in a side-on head-to-tail association with the second uncoordinated acetonitrile at C...N distances of 3.467 (2) and 3.569 (2) Å. In contrast to several related compounds with diaminopyridine- instead of diaminotriazine-based PNP ligands, the title crystal structure is remarkably well ordered. This suggests that the diaminotriazine moiety exerts notable crystal structure stabilizing effects. more...

The title structure, [Fe2(C5H5)2(C14H19BBrN)], contains a chiral and asymmetrically 2,2′′-disubstituted biferrocene designed as precursor for enantioselective non-C2-symmetric biferrocenyldiphosphine catalysts. The mean bond lengths in the biferrocene unit are Fe—C = 2.048 (10) Å and C—C = 1.427 (8) Å within the cyclopentadienyl rings. The B—N bond lengths of the BH3 protected amine is 1.631 (3) Å. The interplanar angle between the two connected cyclopentadienyl rings is 54.29 (8)° and the corresponding Fe—Cg—Cg—Fe torsion angle is −52.5°. The conformation of the molecule is stabilized by an intramolecular C—H...Br interaction. more...

The title compound, C33H49NO3, is the propargylamide of 18β-glycyrrhetinic acid, a pentacyclic triterpenoid of interest as a therapeutic agent. The five six-membered rings of the glycyrrhetinic acid moiety show normal geometries, with four rings in chair conformations and the unsaturated ring C in a half-chair conformation. In the crystal, the terminal N-propargylcarboxamide group has remarkable structural effects on weak hydrogen-bond-like interactions. Particularly noteworthy are an intermolecular O—H...π interaction accepted side-on by the terminal alkyne group [O...C = 3.097 (2) and 3.356 (2) Å] and a short intermolecular C—H...O interaction [C...O = 3.115 (2) Å] donated by the alkyne C—H group. An N—H...O [N...O = 3.251 (2) Å] and a Calkyl—H...O [C...O = 3.254 (2) Å] interaction complement the crystal structure. more...

The racemic title compound, [FePdCl2(C5H5)(C36H29P2)]·2(CH3)2SO, features a Pd-chelating 1,3-diphosphine, which is substituted at a P-bearing asymmetric C atom by a ferrocenyl group. The PdII atom is in a distorted quadratic coordination by two P and two Cl atoms with bond lengths of 2.2414 (3) and 2.2438 (3) Å for Pd—P, and 2.3452 (3) and 2.3565 (3) Å for Pd—Cl. The conformation of the Pd complex is controlled by an intramolecular slipped π–π stacking interaction between a phenyl and a cyclopentadienyl ring with corresponding C...C distances starting at 3.300 (2) Å and the distance between ring centroids being 3.674 (2) Å. The crystal structure is stabilized by C—H...Cl and C—H...O hydrogen bonds. The (CH3)2SO solvent molecules are arranged in layers parallel to (101) and are linked in pairs by C—H...O interactions. One (CH3)2SO molecule is orientationally disordered [occupancy ratio 0.8766 (17):0.1234 (17)] with sulfur in two positions at both sides of its C2O triangle. more...

The asymmetric unit of the title compound, [FeRuCl(C5H5)(C10H14)(C37H31P2)]PF6, contains two independent, geometrically similar RuII complexes of a chiral ferrocenyldiphosphane with piano-stool coordination through the η6-bound p-cymene ligand, two chelating phosphorus donor atoms, and an exo-oriented chloride ion. The mean bond lengths of the two Ru complexes are Ru—C = 2.276 Å, Ru—P = 2.3816 Å, and Ru—Cl = 2.3924 Å. Both chloride ligands form only intramolecular C—H...Cl interactions. Seven weak intermolecular C—H...F interactions involving mainly arene H atoms consolidate the crystal packing, which reveals an approximate c/2 pseudo-translation relating the two independent Ru complex molecules. more...

The herbicide triflusulfuron-methyl (systematic name: methyl 2-{[4-dimethylamino-6-(2,2,2-trifluoroethoxy)-1,3,5-triazin-2-yl]carbamoylsulfamoyl}-3-methylbenzoate) and its degradation product triazine amine [systematic name: 2-amino-4-dimethylamino-6-(2,2,2-trifluoroethoxy)-1,3,5-triazine] form a triclinic 1:1 co-crystal of the title compound, C7H10F3N5O·C17H19F3N6O6S, in which its two components are connected via a pair of complementary N—H...N hydrogen bonds, similar to the monoclinic crystal structure of the parent compound triflusulfuron-methyl [Mereiter (2011). Acta Cryst. E67, o1778–o1779] in which a pair of molecules related by a twofold axis are linked by two N—H...N bonds. The triflusulfuron-methyl molecules of both crystal structures are similar in geometric parameters and conformation, which is due to stiffening by a short intramolecular N—H...N bond [N...N = 2.620 (4) Å] and an intramolecular dipole–dipole interaction between the sulfamide and the carboxyl moieties, with Os...Cc = 2.802 (5) Å and Oc...Ns = 2.846 (4) Å. Intermolecular N—H...O hydrogen bonds and slipped π–π stacking interactions between the diaminotriazine moieties [perpendicular distances of 3.25 Å within hydrogen-bonded tetramers and 3.27 Å between adjacent tetramers] link the two constituents of the co-crystal into columns parallel to the a axis. An intramolecular C—H...O hydrogen bond occurs in the triflusulfuron-methyl molecule and intermolecular C—H...O interactions between triflusulfuron-methyl molecules occur in the crystal structure. In the triflusulfuron-methyl molecule the dihedral angle between the least-squares planes of the two rings is 75.8 (1)°. In the triazine molecule, the CF3 group is partly orientationally disordered. more...

The molecule of the title compound [systematic name: methyl 2-({[4-dimethylamino-6-(2,2,2-trifluoroethoxy)-1,3,5-triazin-2-yl]carbamoyl}sulfamoyl)-3-methylbenzoate], C17H19F3N6O6S, features a nearly planar (r.m.s. deviation = 0.098 Å) dimethylaminotriazinyl-urea group with a short intramolecular N—H...N hydrogen bond to a triazine N atom. An intramolecular dipole–dipole interaction between the sulfamide and carboxylate groups, with Os...Cc = 2.800 (1) Å and Ns...Oc = 2.835 (1) Å, controls the orientation of the methylbenzoate group and the shape of the molecule. The crystal structure is stabilized by intermolecular N—H...N hydrogen bonding, C—H...X (X = N,O) interactions and arene π–π stacking. more...

The title compound, C33H46O7, is an unusual oxydation product of the therapeutic agent glycyrrhetinic acid that has, in comparison to the latter, a distinctly altered triterpene structure with one five- and four six-membered carbocycles complemented by a γ-lactone ring with a spiro-junction and a ring double bond. The junction between the five-membered ring C, a cyclopentanone ring, and the six-membered ring D, previously in question, was found to be cis, confirming earlier structure assignments based solely on chemical transformations. In the solid state, the compound exhibits five intra- and four intermolecular C—H...O interactions with H...O distances less than or equal to 2.70 Å and C—H...O greater than 100°. more...

The crystal structure of the title compound, [Cu(C11H19N2P)2]PF6, is composed of discrete [Cu(PN-iPr)2]+ cations [PN-iPr is 2-(diisopropylphosphanylamino)pyridine] and PF6− anions. The Cu(I) atom is bis-chelated by two independent PN-iPr ligands. It has a distorted tetrahedral coordination by two P atoms [Cu—P = 2.2277 (4) and 2.2257 (4) Å] and two pyridine N atoms [Cu—N = 2.0763 (11) and 2.0845 (12) Å]. Bond angles about Cu vary from 85.11 (3) (P—Cu—N) to 130.37 (2)° (P—Cu—P). In the crystal, N—H...F hydrogen bonds link the Cu complexes and the PF6− anions into continuous chains, which show a cross-bedded spatial arrangement. In addition, several weaker C—H...F interactions contribute to the coherence of the structure. more...

In the title compound, {[Cu(C9H15N13)2](ClO4)2}n, the Cu2+ cation lies on an inversion center and is coordinated by the tetrazole N4 atoms of six symmetry-equivalent tris[2-(1H-tetrazol-1-yl)ethyl]amine ligands (t3z) in the form of a Jahn–Teller-distorted octahedron with Cu—N bond distances of 2.0210 (8), 2.0259 (8) and 2.4098 (8) Å. The tertiary amine N atom is stereochemically inactive. The cationic part of the structure, viz. [Cu(t3z)2]2+, forms an infinite two-dimensional network parallel to (100), in pockets of which the perchlorate anions reside. The individual networks are partially interlocked and held together by C—H...O interactions to the perchlorate anions and C—H...N interactions to tetrazole N atoms. more...

The title compound, [Co(C14H17N5)(C6H7N)](C24H20B) or [Co{(pyrrole)2dien}(4-Mepy)]BPh4 where (pyrrole)2dien is 2,2′-[(3-azapentane-1,5-diylbis(nitrilomethylidyne)]dipyrrole and 4-Mepy is 4-methylpyridine, contains a pentadentate (pyrrole)2dien ligand furnishing an N5 set, such that two of the pyrrole N atoms and two of the dien N atoms occupy the equatorial positions while one of the imine N atoms of the (pyrrole)2dien ligand occupies the axial position. The 4-methylpyridine ligand occupies an axial position trans to one of the imine N atoms of the pentadentate ligand. In the observed conformation of the pentadentate ligand, the pyrrole rings attain asymmetrical positions owing to the structural demands. The geometry of the resulting CoN6 coordination can be described as distorted octahedral. more...

The title compound, [RuCl2(C8H6O)(C21H26N2)]·C4H10O, contains a catalytically active ruthenium carbene complex of the `second-generation Grubbs/Hoveyda' type with Ru in a square-pyramidal coordination, the apex of which is formed by the benzylidene carbene atom with Ru=C 1.827 (2) Å. The complex shows the uncommon cis, rather than the usual trans, arrangement of the two chloride ligands, with Ru—Cl bond lengths of 2.3548 (6) and 2.3600 (6) Å, and a Cl—Ru—Cl angle of 89.76 (2)°. This cis configuration is desirable for certain applications of ring-opening metathesis polymerization (ROMP) of strained cyclic olefins. The crystalline solid is a diethyl ether solvate, which is built up from a porous framework of Ru complexes held together by π–π stacking and C—H...Cl and C—H...O interactions. The disordered diethyl ether solvent molecules are contained in two independent infinite channels, which extend parallel to the c axis at x,y = 0,0 and x,y = {1over 2},{1over 2} and have solvent-accessible void volumes of 695 and 464 Å3 per unit cell. more...

The title compound, [Ru(C5H5)(C3H5N)(C18H15P)2]CF3SO3, forms yellow crystals with a distinctly hemimorphic habit. It contains a half-sandwich complex of ruthenium with a three-legged piano-stool geometry, with Ru—P = 2.3585 (4) and 2.3312 (4) Å, and Ru—N = 2.0422 (15) Å as the legs. The CF3SO3− anion is anchored in the crystal lattice by C—H...O and C—H...F hydrogen bonds, with C...F,O distances starting at 3.125 (2) Å. more...

The title compound, C16H14N8, is a new chiral ligand designed for applications in supramolecular chemistry and Fe2+ spin-crossover complexes. The crystal structure shows a herring-bone arrangement of the molecules, which are mutually linked via intermolecular C—H...N interactions mainly donated by the alkyl and tetrazole H atoms. more...

In the title compound, [Fe(H2O)6][FeBr3(CO)3]2, both Fe atoms have an octahedral coordination and the bromide carbonyl complex has a fac-stereochemistry. The [Fe(H2O)6]2+ octahedron has point symmetry overline{1} and is slightly compressed along one O—Fe—O axis. The [FeBr3(CO)3]− anion has point symmetry 1 and mean bond lengths of Fe—Br = 2.455 (5) Å and Fe—C = 1.809 (2) Å. The cation and anion complexes are mutually linked via O—H...Br hydrogen bonds with O...Br distances of 3.340 (3) to 3.388 (3) Å. more...

The title compound [systematic name: (1S,3aS,4aR,4bS,5S,6R,6aR,10aR,10bR,12aS)-5,6-bis(acetyloxy)-1-(3-furyl)-1,5,6,6a,7,10a,10b,11,12,12a-decahydro-4b,7,7,10a,12a-pentamethyloxireno[c]phenanthro[1,2-d]pyran-3,8(3aH,4bH)-dione], C30H36O9, is a limonoid-type triterpene isolated from Aglaia elaeagnoidea (A. Juss.) Benth. (Meliaceae) from Queensland, northern Australia. It contains the gedunin core of four trans-fused six-membered rings with an oxirane ring annelated to the fourth ring. A terminal 3-furyl unity and two acetoxy groups in a mutual cis-disposition supplement the molecule. A comparison between the gedunin cores of the title compound, the parent compound gedunin, and three further gedunin derivatives revealed considerable variations in their conformation stemming from the conformational lability of the first screw-boat ring and the third twist-boat ring. A sensitive measure for the third ring is one C—C—C—C torsion angle, which is 14.2 (2)° in the title compound, but varies in other cases from ca 20 to ca −40°. In the crystalline state, 6α-acetoxygedunin shows ten comparatively weak C—H...O interactions, with H...O distances in the range of 2.33–2.69 Å. more...

The title compound, [Co(C20H14N2O2)(C5H5N)2]ClO4 or [Co(salophen)(py)2]ClO4, where salophen is o-phenylenebis(nitrilomethylidyne)]diphenolate and py is pyridine, contains a six-coordinate mononuclear cobalt(III) atom. The two phenolic O atoms and the two imine N atoms are located in cis positions. There are two pyridine molecules attached to the metal atom, filling the axial sites with a mutually perpendicular disposition of the pyridine planes [86.11 (5)°]. The Co complexes are stacked in layers parallel to (100). Coherence of the structure is provided by a variety of C—H...O interactions between the complexes and the perchlorate counter anion. more...

The title compound, [Ru(C10H15)Cl(C12H10ClP)(C17H20NP)], is a half-sandwich complex of RuII with the chlorodiphenylphosphine ligand formed from the diphenylpiperidinophosphine and chlorine of the precursor complex [Ru(η5-C5Me5)(κ1P—Ph2PNC5H10)Cl2] by an unexpected reaction with NaBH4. The complex has a three-legged piano-stool geometry, with Ru—P bond lengths of 2.2598 (5) Å for the chlorophosphine and 2.3303 (5) Å for the aminophosphine. more...

The title compound, [Ru(η5-C5H5){η6-C6H2(CH3)3NH2}]PF6, contains a sandwich complex with a mesitylamine unit which is significantly non-planar at the ipso-carbon of the amino group due to repulsive electronic effects with Ru. The ipso-carbon deviates by 0.107 (3) Å from the least-squares plane of the remaining five benzene ring atoms, which show an r.m.s. deviation of 0.005 Å. N—H...F hydrogen-bonding interactions help to consolidate the crystal packing. more...

The title compound, [Cu(C23H24N2O2)] or [Cu{(BA)2pn}], where (BA)2pn is 1,1′-diphenyl-3,3′-(propane-1,3-diyldinitrilo)dibut-1-enolate, is a mononuclear copper(II) complex, located on a twofold axis. The four-coordinate CuII atom is in a tetrahedrally distorted square plane defined by the N and O atoms of the Schiff base ligand. In the tetradentate ligand, the two chelate rings are twisted relative to each other, making a dihedral angle of 36.57 (3)°. more...