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1.
Crystal Structure of [BeCl2(15‐Crown‐5)] Single crystals of [BeCl2(15‐crown‐5)] ( 1 ) were obtained from dichloromethane solutions of BeCl2 in the presence of the equivalent amount of 15‐crown‐5 and characterized by IR spectroscopy and X‐ray diffraction. Space group P21/c, Z = 4, lattice dimensions at 100 K: a = 1036.2(1), b = 1071.1(1), c = 1360.1(1) pm, β = 109.86(1)°, R1 = 0.0225. The structure determination shows no disorder, all hydrogen positions were refined isotropically. The results are in contrast to the previously reported crystal structure determination in the space group P21nb. The beryllium atom of 1 forms a BeO2C2 five‐membered heterocycle with terminal chlorine atoms to give a distorted tetrahedral coordination with distances Be–O 166.5(2), 169.9(2) pm, and Be–Cl 195.8(2), 197.8(2) pm. The structural results are in good agreement with DFT calculations on B3LYP/6‐311+G** level.  相似文献   

2.
The seven‐membered beryllium‐containing heterocycle beryllepin, C6H6Be, has been examined computationally at the B3LYP/6‐311++G** density functional level of theory. Beryllepin is best described as a planar singlet heterocyclic conjugated triene with marginal aromatic character containing a C–Be–C moiety forced to be nonlinear (∠C‐Be‐C = 146.25°) by the cyclic constraints of the seven‐membered ring. The molecule can be considered to be derived from a benzene‐like system in which a neutral beryllium atom has been inserted between two adjacent carbon atoms. The 11 other possible “beryllium‐inserted benzenes,” C6H6Ben, n = 2–6, have also been investigated. Only two of these heterocyclic systems, the eight‐membered 1,4‐diberyllocin and the nine‐membered 1,4,7‐triberyllonin, were found to be stable, singlet‐ground‐state systems, albeit with little aromatic character. Of the remaining nine beryllium‐inserted benzenes, with the exception of the 11‐membered ring containing five beryllium atoms and the 12‐membered ring containing six beryllium atoms, which were calculated to exist as a ground state pentet and septet, respectively, all were calculated to be ground state triplet systems.  相似文献   

3.
In the first title salt, [Cu(C12H8N2)2(C5H10N2Se)](ClO4)2, the CuII centre occupies a distorted trigonal–bipyramidal environment defined by four N donors from two 1,10‐phenanthroline (phen) ligands and by the Se donor of a 1,3‐dimethylimidazolidine‐2‐selone ligand, with the equatorial plane defined by the Se and by two N donors from different phen ligands and the axial sites occupied by the two remaining N donors, one from each phen ligand. The Cu—N distances span the range 1.980 (10)–2.114 (11) Å and the Cu—Se distance is 2.491 (3) Å. Intermolecular π–π contacts between imidazolidine rings and the central rings of phen ligands generate chains of cations. In the second salt, [Cu(C10H8N2)2(C3H6N2S)](ClO4)2, the CuII centre occupies a similar distorted trigonal–bipyramidal environment comprising four N donors from two 2,2′‐bipyridyl (bipy) ligands and an S donor from an imidazolidine‐2‐thione ligand. The equatorial plane is defined by the S donor and two N donors from different bipy ligands. The Cu—N distances span the range 1.984 (6)–2.069 (7) Å and the Cu—S distance is 2.366 (3) Å. Intermolecular π–π contacts between imidazolidine and pyridyl rings form chains of cations. A major difference between the two structures is due to the presence in the second complex of two N—H...O hydrogen bonds linking the imidazolidine N—H hydrogen‐bond donors to perchlorate O‐atom acceptors.  相似文献   

4.
Tetra(N,N′‐tetramethylurea)‐beryllium‐triiodide, [Be(TMU)4](I3)2 ( 1 ) was prepared from beryllium powder and iodine in N,N′‐tetramethylurea to give orange crystals, which were characterized by X‐ray diffraction and IR spectroscopy. Compound 1 crystallizes monoclinically in the space group C2/c with four formula units per unit cell. Lattice dimensions at 100(2) K: a = 1906.6(1), b = 1185.7(1), c = 1895.0(1) pm, β = 113.60(1) °, R1 = 0.0291. The structure of 1 consists of distorted tetrahedral cations [Be(TMU)4]2+ with Be–O bond lengths of 162.5(5) and 160.8(5) pm and triiodide ions without site symmetry.  相似文献   

5.
Single crystals of [Be33‐O)3(MeCN)6{Be(MeCN)3}3](I)6·4CH3CN ( 1 ·4CH3CN) were obtained in low yield by the reaction of beryllium powder with iodine in acetonitrile suspension, which probably result from traces of beryllium oxide containing the applied beryllium metal. The compound 1 ·4CH3CN forms moisture sensitive, colourless crystal needles, which were characterized by IR spectroscopy and X‐ray diffraction (Space group Pnma, Z = 4, lattice dimensions at 100(2) K: a = 2317.4(1), b = 2491.4(1), c = 1190.6(1) pm, R1 = 0.0315). The hexaiodide complex cation 1 6+consists of a cyclo‐Be3O3 core with slightly distorted chair conformation, stabilized by coordination of two acetonitrile ligands at each of the beryllium atoms and by a {Be(CH3CN)3}2+ cation at each of the oxygen atoms. This unique coordination behaviour results in coplanar OBe3 units with short Be–O distances of 155.0 pm and 153.6 pm on average of bond lengths within the cyclo‐Be3O3 unit and of the peripheric BeO bonds, respectively. Exposure of compound 1 ·4CH3CN to moist air leads to small orange crystal plates of [Be(H2O)4]I2·2CH3CN ( 3 ·2CH3CN). According to the crystal structure determination (Space group C2/c, Z = 4, lattice dimensions at 100(2) K: a = 1220.7(1), b = 735.0(1), c = 1608.5(1) pm, β = 97.97(1)°, R1 = 0.0394), all hydrogen atoms of the dication [Be(H2O)4]2+ are involved to form O–H ··· N and O–H ··· I hydrogen bonds with the acetonitrile molecules and the iodide ions, respectively. Quantum chemical calculations (B3LYP/6‐311+G**) at the model [Be33‐O)3(HCN)6{Be(HCN)3}3]6+ show that chair and boat conformation are stable and that the distorted chair conformation is stabilized by packing effects.  相似文献   

6.
The asymmetric unit of the title two‐dimensional coordination polymer, [Co2(C16H6O8)(C14H14N4)2]n, contains one Co2+ ion, half of a biphenyl‐3,3′,4,4′‐tetracarboxylate (bptc) anion lying about an inversion centre and one 1,4‐bis(imidazol‐1‐ylmethyl)benzene (bix) ligand. The CoII atom is coordinated by three carboxylate O atoms from two different bptc ligands and two N atoms from two bix ligands constructing a distorted square pyramid. Each Co2+ ion is interlinked by two bptc anions, while each bptc anion coordinates to four Co atoms as a hexadentate ligand so that four CoII atoms and four bptc anions afford a larger 38‐membered ring. These inorganic rings are further extended into a two‐dimensional undulated network in the (10) plane. Two CoII atoms in adjacent 38‐membered rings are joined together by pairs of bix ligands forming a 26‐membered [Co2(bix)2] ring that is penetrated by a bptc anion; these components share a common inversion centre.  相似文献   

7.
Single crystals of a new rubdidium beryllium borate, RbBe4(BO3)3, have been obtained by spontaneous nucleation from a high‐temperature melt. This new ortho­rhom­bic (Pnma) structure type contains [Be2BO4] rings, made of two BeO4 tetra­hedra and one BO3 triangle, which constitute the basic structural units. The m plane runs through the B and one of the O atoms and intersects the ring. These rings form chains in the a direction, which are connected in the b and c directions to form zeolite‐type cages in which the Rb+ cations are located, at sites of m symmetry.  相似文献   

8.
The title compound, [Sr(C7H5O4)2(C12H8N2)2(H2O)2]·2C12H8N2·4H2O, consists of an SrII complex, uncoordinated phenanthroline (phen) molecules and solvent water molecules. The SrII ion is located on a twofold axis and is coordinated by two phen ligands, two dihydroxybenzoate anions and two water molecules in a distorted tetragonal antiprismatic geometry. Partially overlapped arrangements exist between parallel coordinated and parallel uncoordinated phen rings; the face‐to‐face separations between the former (coordinated) and the latter (uncoordinated) rings are 3.436 (13) and 3.550 (14) Å, respectively. This difference suggests the effect of metal coordination on π–π stacking between phen rings.  相似文献   

9.
The title compound, [Ni(BMTT)2], where BMTT is 1,3‐bis(2‐methyl­tetrazol‐5‐yl)­triazenide (C4H6N11), presents a molecular complex with tridentate ligands. The tridentate mode of the ligand is realised through the central N atom of the triazene group and two N atoms of the two tetrazole rings. The [Ni(BMTT)2] mol­ecule is the meridional isomer, with crystallographic symmetry in space group P42/n. The nickel centre has a distorted octahedral environment, with two axial Ni—N bonds of 2.041 (2) Å and four equatorial Ni—N bonds of 2.0739 (14) Å. The mol­ecules are linked together by van der Waals interactions only.  相似文献   

10.
In the structure of the first bis‐adduct of 2,5‐bis­[3‐(tert‐butyl­aminoxyl)­phenyl]‐1,1‐dimethyl‐3,4‐diphenyl­silole with bis­(hexa­fluoro­acetyl­acetonato)­manganese(II), [Mn(C5HF6O2)2(C38H42N2O2Si)2], the Mn atom lies on a crystallographic inversion centre and is bound to two chelating hexafluoro­acetylacetonate ligands and two monodentate nitroxide groups in a distorted octa­hedral configuration. The silole ligands present a propeller‐like arrangement of the benzene rings around the Si‐containing five‐membered ring. The dihedral angles between the complexed nitroxides and the benzene rings to which they are bound are smaller than those found in the free ligand.  相似文献   

11.
Molecules of 2‐amino‐4,6‐di­methoxy­pyrimidine, C6H9N3O2, (I), are linked by two N—H?N hydrogen bonds [H?N 2.23 and 2.50 Å, N?N 3.106 (2) and 3.261 (2) Å, and N—H?N 171 and 145°] into a chain of fused rings, where alternate rings are generated by centres of inversion and twofold rotation axes. Adjacent chains are linked by aromatic π–π‐stacking interactions to form a three‐dimensional framework. In 2‐­benzylamino‐4,6‐bis(benzyloxy)pyrimidine, C25H23N3O2, (II), the mol­ecules are linked into centrosymmetric R(8) dimers by paired N—H?N hydrogen bonds [H?N 2.13 Å, N?N 2.997 (2) Å and N—H?N 170°]. Molecules of 2‐amino‐4,6‐bis(N‐pyrrolidino)­pyrimidine, C12H19N5, (III), are linked by two N—H?N hydrogen bonds [H?N 2.34 and 2.38 Å, N?N 3.186 (2) and 3.254 (2) Å, and N—H?N 163 and 170°] into a chain of fused rings similar to that in (I).  相似文献   

12.
Bis(tetraphenylphosphonium) hexachloridodiberyllate, (Ph4P)2[Be2Cl6], reacts with excess trimethylsilyl‐iso‐thiocyanate to give a mixture of colourless single crystals of (Ph4P)2[Be(NCS)4] ( 1 ) and (Ph4P)4[{Be2(NCS)4(μ‐NCS)2}{Be2(NCS)6(μ‐H2N2C2S2)}] ( 2 ), which can be separated by selection. Both complexes were characterized by X‐ray diffraction. Compound 1 can be prepared without by‐products by treatment of (Ph4P)2[BeCl4] with excess Me3SiNCS in dichloromethane solution. 1 : Space group I41/a, Z = 4, lattice dimensions at 100(2) K: a = b = 1091.2(1), c = 3937.1(3) pm, R1 = 0.0474. The [Be(NCS)4]2– ion of 1 forms tetragonally distorted tetrahedral anions with Be–N distances of 168.4(2) pm and weak intermolecular S ··· S contacts along [100] and [010]. 2 ·4CH2Cl2: Space group P , Z = 1, lattice dimensions at 100(2) K: a = 919.5(1), b = 1248.3(1), c = 2707.0(2) pm, α = 101.61(1) °, β = 95.08(1) °, γ = 94.52(1) °, R1 = 0.103. Compound 2 contains two different anionic complexes in the ratio 1:1. In {Be2(NCS)4(μ‐NCS)2}2–, the beryllium atoms are connected by (NCS) bridging groups forming centrosymmetric eight‐membered Be2(NCS)2 rings with distances Be–N of 168(1) pm and Be–S of 235.2(9) pm. The second anion {Be2(NCS)6(μ‐H2N2C2S2)}2– consists of two {Be(NCS)3} units, which are linked by the nitrogen atoms of the unique dimeric cyclo‐addition product of HNCS with Be–N distances of 179(1) pm.  相似文献   

13.
In the title compound, [Cd(C12H8F2N3)2(C5H5N)2], the Cd atom lies on a crystallographic twofold axis in space group Iba2. The coordination geometry about the CdII ion corresponds to a rhombically distorted octahedron, with two deprotonated 1,3‐bis(2‐fluoro­phenyl)­triazenide ions, viz. FC6H4NNNC6H4F, acting as bidentate ligands (four‐electron donors). Two neutral pyridine (py) mol­ecules complete the coordination sphere in positions cis with respect to one another. The triazenide ligand is not planar (r.m.s. deviation = 0.204 Å), the dihedral angle between the phenyl rings of the terminal 2‐fluoro­phenyl substituents being 24.6 (1)°. The triazenide and pyridine Cd—N distances are 2.3757 (18)/2.3800 (19) and 2.3461 (19) Å, respectively. Intermolecular C—H⋯F interactions generate sheets of mol­ecules in the (010) plane.  相似文献   

14.
In the title compound, [Co(C2H6NS)(C2H8N2)2](NO3)2, the CoIII atom has a slightly distorted octahedral geometry, coordinated by one 2‐amino­ethane­thiol­ate and two ethyl­enedi­amine ligands. The three five‐membered chelate rings adopt a gauche conformation with the unfavoured (lel)2(ob) form, which is ascribed to hydrogen bonds between the amine groups in the complex cation and the nitrate counter‐anions [N?O 2.900 (3)–3.378 (3) Å].  相似文献   

15.
The crystal structure of the heterobimetallic title compound, [ReRuCl(C10H16As2)2(C10H8N2)2(CO)3](PF6)2·2C3H6O, is described. Both metal centres have pseudo‐octahedral coordination geometries, with a facial arrangement of the carbonyl ligands at ReI and a trans disposition of the diarsine ligands at RuII. The dihedral angle between the pyridyl rings of the 4,4′‐bi­pyridine bridging ligand is 13.9 (6)°.  相似文献   

16.
In the title salt, (C6H8N4)[Mn(C14H8O4)2(C6H6N4)2]·6H2O, the MnII atom lies on an inversion centre and is coordinated by four N atoms from two 2,2′‐biimidazole (biim) ligands and two O atoms from two biphenyl‐2,4′‐dicarboxylate (bpdc) anions to give a slightly distorted octahedral coordination, while the cation lies about another inversion centre. Adjacent [Mn(bpdc)2(biim)2]2− anions are linked via two pairs of N—H...O hydrogen bonds, leading to an infinite chain along the [100] direction. The protonated [H2biim]2+ moiety acts as a charge‐compensating cation and space‐filling structural subunit. It bridges two [Mn(bpdc)2(biim)2]2− anions through two pairs of N—H...O hydrogen bonds, constructing two R22(9) rings, leading to a zigzag chain in the [2] direction, which gives rise to a ruffled set of [H2biim]2+[Mn(bpdc)2(biim)2]2− moieties in the [01] plane. The water molecules give rise to a chain structure in which O—H...O hydrogen bonds generate a chain of alternating four‐ and six‐membered water–oxygen R42(8) and R66(12) rings, each lying about independent inversion centres giving rise to a chain along the [100] direction. Within the water chain, the (H2O)6 water rings are hydrogen bonded to two O atoms from two [Mn(bpdc)2(biim)2]2− anions, giving rise to a three‐dimensional framework.  相似文献   

17.
Metal Salts of Benzene‐1, 2‐di(sulfonyl)amine. 8. Lamellar Layers Based upon Hydrogen Bonding and π‐Stacking: Crystal Structures of the Complexes [Mg(H2O)6]Z2 and [Be(H2O)4]Z2�2 H2O, where Z is C6H4(SO2)2N The crystal structures of the title complexes (both triclinic, space group P1¯, Z = 1 for M = Mg, Z = 2 for M = Be) have been determined by low‐temperature X‐ray diffraction. They consist of non‐coordinating ortho‐benzenedisulfonimide anions and, respectively, inversion‐symmetric octahedral [Mg(H2O)6]2+ cations or tetrahedral [Be(H2O)4]2+ cations and two non‐coordinating water molecules. In both structures, all O—H hydrogen bond donor groups are used to associate the components into two‐dimensional assemblies comprising an internal polar lamella of metal cations, (SO2)2N groups and water molecules, and hydrophobic peripheral regions consisting of vertically protruding benzo rings. Carbocycles drawn alternatingly from adjacent layers form π‐stacking arrays, whereby the aromatic rings display intercentroid distances in the range 340—370 pm. Several short C—H ⃜O contacts, which may be viewed as weak hydrogen bonds, occur within and between the layers.  相似文献   

18.
The pyrimidine rings in ethyl (E)‐3‐[2‐amino‐4,6‐bis(dimethylamino)pyrimidin‐5‐yl]‐2‐cyanoacrylate, C14H20N6O2, (I), and 2‐[(2‐amino‐4,6‐di‐1‐piperidylpyrimidin‐5‐yl)methylene]malononitrile, C18H23N7, (II), which crystallizes with Z′ = 2 in the space group, are both nonplanar with boat conformations. The molecules of (I) are linked by a combination of N—H...N and N—H...O hydrogen bonds into chains of edge‐fused R22(8) and R44(20) rings, while the two independent molecules in (II) are linked by four N—H...N hydrogen bonds into chains of edge‐fused R22(8) and R22(20) rings. This study illustrates both the readiness with which highly‐substituted pyrimidine rings can be distorted from planarity and the significant differences between the supramolecular aggregation in two rather similar compounds.  相似文献   

19.
Preparation, Crystal Structure and IR Spectra of BeSeO3 · H2O – Hydrogen Bonds and Correlation of IR and Structure Data in the Monohydrates MSeO3 · H2O (M = Be, Ca, Mn, Co, Ni, Zn, Cd) BeSeO3 · H2O (oP32) has been obtained by treating amorphous BeSeO3 · 4 H2O precipitated from Be(HSeO3)2 solutions hydrothermally at 150 °C. The crystal structure (P212121, a = 560.59(4), b = 755.25(5), c = 781.14(5) pm, Z = 4, DX = 3.092 gcm–3, R = 0.018 for the 2034 reflections with I > 2σI of the enantiomer investigated) contains BeO3(H2O) tetrahedra built up from three selenite and one water oxygen atoms. The BeO3(H2O) tetrahedra are 3 D‐connected via Se atoms of trigonal pyramidal SeO32– ions. The Be–O distances are 161.8 to 164.4 pm. The Se–O bond lenghts (169.2–170.3 pm) and the O–Se–O bond angles (98.1–101.4°) are normal. The water molecules of crystallization form together with the SeO32– ions screw‐like hydrogen bond systems along [100]. Despite the strong synergetic effect of the Be2+ ions, the hydrogen bonds (d(OH…O) = 267.4 and 276.4 pm, respectively; νOD of matrix isolated HDO molecules: 2244 and 2405 cm–1, respectively) are normal compared to other neutral selenite hydrates. Together with the hitherto known monohydrates MIISeO3 · H2O and other beryllium salt hydrates, the hydrogen bonds of BeSeO3 · H2O are discussed with regard to their geometry and IR spectroscopy.  相似文献   

20.
In the structures of the two title calix[4]arene derivatives, C32H28N12O4, (I), and C60H68Cl2N2O6, (II), compound (I) adopts an open‐cone conformation in which there are four intramolecular O—H...O hydrogen bonds, while compound (II) adopts a distorted chalice conformation where the two pendant pyridyl rings, one of which is disordered, are almost mutually perpendicular, with an interplanar angle of 79.2 (2) or 71.4 (2)°. The dihedral angles between the virtual plane defined by the four bridging methylene C atoms and the phenol rings are 120.27 (7), 124.03 (6), 120.14 (8) and 128.25 (7)° for (I), and 95.99 (8), 135.93 (7), 97.21 (8) and 126.10 (8)° for (II). In the supramolecular structure of (I), pairs of molecules associate by self‐inclusion, where one azide group of the molecule is inserted into the cavity of the inversion‐related molecule, and the association is stabilized by weak intermolecular C—H...N hydrogen bonds and π(N3)–π(aromatic) interactions. The molecular pairs are linked into a two‐dimensional network by a combination of weak intermolecular C—H...N contacts. Each network is further connected to its neighbor to produce a three‐dimensional framework via intersheet C—H...N hydrogen bonds. In the crystal packing of (II), the molecular components are linked into an infinite chain by intermolecular C—H...O hydrogen bonds. This study demonstrates the ability of calix[4]arene derivatives to form self‐inclusion structures.  相似文献   

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