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1.
The structure of the title compound (systematic name: 3,7‐di­bromo‐2‐hydroxy‐6‐iso­propyl­cyclo­hepta‐2,4,6‐trien‐1‐one), C10H10Br2O2, previously described by Ito, Fukazawa & Iitaka [Tetrahedron Lett. (1972), 13 , 745–749], has been redetermined. Strong inter‐ and intramolecular hydrogen bonds, with H...O distances of 2.17 (9) and 2.06 (6) Å, respectively, are observed. There are also two short Br...Br and two short Br...(ring centroid) interactions. Important dimensions include C—O(carbonyl) = 1.252 (5) Å, C—O(hydroxyl) = 1.355 (5) Å, C—Br(3‐position) = 1.904 (4) Å and C—Br(7‐­position) = 1.905 (4) Å, and an O—C—C—O ring torsion angle of −6.7 (6)°.  相似文献   

2.
The centrosymmetric binuclear manganese(II) nitrate complex with a bicyclic bis-carbamide, namely, 2,4,6,8-tetramethyl-2,4,6,8-tetraazabicyclo(3.3.0)octane-3,7-dione, or mebicar (Mk) [Mn(C8H14N4O2)(H2O)(NO3)2]2 · H2O (I), has been synthesized for the first time. The structure of complex I has been solved (CCDC no. 1435139). Crystals of complex I are monoclinic, space group P21/c, a = 12.8108(11) Å, b = 10.0662(2) Å, c = 18.6367(17) Å, β = 136.512(16)°, V = 1654.0(4) Å3, ρcalcd = 1.659 g/cm3, Z = 2. Each manganese atom is coordinated to the two oxygen atoms of two Mk molecules related by the symmetry codes (1–x, 2–y, 1–z) and to two bidentate nitrate anions and one water molecule. The coordination polyhedron of the manganese atom is a strongly distorted pentagonal bipyramid. The Mn···Mn distance in the complex is 8.7261(9) Å.  相似文献   

3.
The centrosymmetric binuclear complex of samarium(III) nitrate with bicyclic biscarbamide 2,4,6,8-tetramethyl-2,4,6,8-tetraazabicyclo(3.3.0)octane-3,7-dione, or mebicar (Mk) namely, [Sm(C8H14N4O2)(H2O)2(NO3)3]2 (I) has been synthesized. Its crystal structure has been characterized (CIF file CCDC no. 1451436). Crystals of complex I are triclinic, space group P1 a = 9.8661(2) Å, b = 10.2913(3) Å, c = 10.9629(3) Å, α = 74.475(2)°, β = 67.802(2)°, γ = 67.570(2)°, V = 942.68(5) Å3, ρcalcd = 2.01028 g/cm3, and Z = 1. The samarium atom is coordinated by the two oxygen atoms of two Mk molecules bonded via the symmetry center, three bidentate nitrate anions, and two water molecules. The coordination number of the samarium atom is 10, the coordination polyhedron of the metal atom is a decahedron and the Sm…Sm distance is 9.7904(4) Å.  相似文献   

4.

The unusual chiral heterocyclic systems, trioxabicyclo[3.3.1]nona-3,7-dienes ("bridged bisdioxines"), are incorporated as novel spacer molecules into macrocyclic polyether ring systems of various sizes (8, 9 as well as 11-15) by cyclocondensation reaction of the bisacid chloride 4b or bisesters 6,7 and 10, with several ethylene glycols. The 2:2 macrocycles 12-14 are obtained in approximately 50:50 mixtures of diastereomers. These conclusions are mainly based on HPLC data presented in Table I as well as X-ray analyses of (1R,5R)-8c (space group Pbca, a =10.163(3) Å, b =18.999(4) Å, c =36.187(10) Å, V =6987(3) Å3 , Z =8, d calc =1.218 g cmm 3, 6974 reflections, R =0.0553), meso/rac-11 (space group P1 ¥ , a =10.472(5) Å, b=16.390(5) Å, c =17.211(5) Å, f =98.69(2)°, g =93.04(2)°, n =98.52(2)°, V =2879.3(18) Å 3 , Z =2, d calc =1.173 g cm m 3 , 11,162 reflections, R =0.0945) and meso-12 (space group P21/c, a =9.927(2), b =18.166(3), c =17.820(3) Å, g =96.590(10)°, V =3192.3(10) Å 3 , Z =4, D c =1.109 g cmm 3, 3490 reflections, R =0.0646). The 1:1 macrocycles 8b,c are also formed by intramolecular transesterification of the open-chain bisesters 7b,c and their formation is favored by the use of metal ions as templates. The bridged bisdioxine moieties in 8b and 12 are converted into the corresponding chiral tetraoxaadamantane spacers to afford macrocycles 16 and 17. Preliminary metal ion complexation studies with selected species (8c, 11-14) were also performed.  相似文献   

5.
A centrosymmetric binuclear complex of europium(III) nitrate with bicyclic bisurea (2,4,6,8-tetramethyl-2,4,6,8-tetraazabicyclo(3.3.0)octane-3,7-dione, or mebicar, Mk) [Eu(C8H14N4O2)(H2O)2(NO3)3]2 (I) is synthesized and its atomic structure (CIF file CCDC No. 1451437) is determined. The crystals of I are triclinic: space group \(P\overline 1 \), a = 9.8343(4) Å, b = 10.2544(4) Å, c = 10.9411(4) Å, α = 74.366(3)°, β = 67.734(4)°, γ = 67.673(4)°, V = 934.32(7) Å3, ρ(calc.) = 2.03398 g/cm3, Z = 1. The europium atom is coordinated by two oxygen atoms of two Mk molecules connected by a symmetry operation, three bidentate nitrate anions, and two water molecules. The coordination polyhedron of the europium atom is a 10-vertex polyhedron, the Eu…Eu distance is 9.7433(6) Å.  相似文献   

6.
Die erste Röntgenstrukturanalyse eines 3,7-Dehydrotropon ( 1 )-Derivates, nämlich von 2-Diisopropylammo-3,7-dehydrotropon ( 4 ) zeigt das Ringsystem in 4 als planaren Bicyclus mit nahezu C2V-Symmetrie. Dementsprechend enthalten Dehydrotropone formell zwei trans-konfigurierte Doppelbindungen in einem 7-gliedrigen Ring; auch das O-Atom und das N-Atom mit seinen Ligandatomen liegen in derselben Ebene wie die Ringatome. Die Bindung zwischen den beiden C-Atomen, welche die Heteroatome tragen, (C(1) and C(2)), ist wesentlich langer (1,56 Å) als die anderen Bindungen im Ringsystem (1,37-1,46 Å). Dies impliziert eine ‘push-pull’-π-Elektronen-Delokalisierung, in der auch das O-und das N-Atom involviert sind, und macht eine ‘aromatische’ Ring-Delokalisierung weniger wahr-scheinlich. Im Gegensatz zu 2-(t-Butyl)-3,7-dehydrotropon ( 3 ) existiert das 2-Diiso-propylamino-3,7-dehydrotropon ( 4 ) im Kristall als Monomeres, was dem stabili-sierenden Einfluss der ‘push-pull’-Delokausierung zugeschrieben werden kann.  相似文献   

7.
Compounds [Rh(NH3)5(NO2)](NO3)2·H2O (I) with a = 7.6230(3) Å, b = 7.6230(3) Å, c = 10.3584(4) Å, space group I-42m, Z = 2, d calc = 2.026 g/cm3, V = 601.93(4) Å3, Rh-NH3 eq = 2.074 Å, Rh-NH3 ax (NO2) = 2.048 Å; [Rh(NH3)5(NO2)][Pd(NO2)4] (II) with a = 8.095(3) Å, b = 22.422(8) Å, c = 7.887(3) Å, β = 98.559(17)°, space group Cc, Z = 4, d calc = 2.461 g/cm3, V = 1415.6(9) Å3, Rh-NH3 eq = 2.069 Å, Rh-NH3 ax = 2.090 Å, Rh-NO2 = 2.002 Å; K2[Rh(NH3)(NO2)5]·H2O (III) with a = 7.5177(5) Å, b = 20.9856(15) Å, c = 7.7017(5) Å, space group Cmc21, Z = 4, d calc = 2.439 g/cm3, V = 1215.05(14) Å3, Rh-NH3 ax (NO2) = 2.094 Å, Rh-NO2 eq = 2.030 Å are synthesized and studied using single crystal X-ray diffraction.  相似文献   

8.
Two bis-chelates M(tmih)2 (M = Cu(II), Ni(II), tmih = (CH3)3C(NCH3)CHCOC(CH3)3)? are synthesized and their crystal structures are determined using XRD (Bruker APEX-II diffractometer with a CCD detector, λMoK α, λCuK α, graphite monochromator, T = 240(2) K and 296(2) K): Cu(tmih)2 (I) (space group P21/c, a = 12.9670(8) Å, b = 18.4921(9) Å, c = 11.0422(6) Å, β = 93.408(4)°, V = 2643.1(3) Å3, Z = 4) and Ni(tmih)2 (II) (space group P21/c, a = 12.810(2) Å, b = 18.529(2) Å, c = 11.243(2) Å, β = 91.959(7)°, V = 2667.1(6) Å3, Z = 4). The complexes are isostructural; the coordination polyhedron of metal atoms is a flattened tetrahedron formed from two O atoms (Cu-O of 1.901(2) Å, 1.892(2) Å, Ni-O of 1.845(2) Å, 1.833(2) Å) and two N atoms (Cu-N of 1.976(3) Å, 1.972(3) Å, Ni-N of 1.911(2) Å, 1.920(2) Å) of the ligand; the chelate OMN angles (M = Cu(II), Ni(II)) are in the 87.4–93.1° range; the OMO and NMN angles are 162.2° and 167.2° in I, 171.1° and 173.2° in II. The complexes have the molecular structures formed from isolated molecules bonded by van der Waals interactions. Using a quantum chemical hybrid M06 method, the structures of copper(II) chelates with the H, CH3, CH2CH3, CH(CH3)2, and C(CH3)3 substituents at the nitrogen atom are calculated. Found that with a bulky substituent at the nitrogen atom, the formation of chelates is hindered due to the intraligand repulsion between the atoms of this substituent and the tert-butyl group.  相似文献   

9.
The synthesis and X-ray single crystal study of two mixed-ligand Cu(II) complexes are performed: (CH3C(NCH3)CHC(O)CH3)(CF3C(O)CHC(O)CF3)Cu (1) (space group P21/c, a = 7.0848(12) Å, b = 17.854(3) Å, c = 11.837(2) Å, β = 100.495(6)°, V = 1472.4(4) Å3, Z = 4), (CH3C(NC6H5)CHC(O)CH3)· (CF3C(O)CHC(O)CF3)Cu (2) (space group P-1, a = 9.1119(4) Å, b = 9.6954(4) Å, c = 11.1447(6) Å, α = 113.784(2)°, β = 92.383(2)°, γ = 95.402(2)°, V = 893.52(7) Å3, Z = 2). The structures are molecular, formed from neutral mixed-ligand copper complexes. The central copper atom has the (3O+N) coordination environment with average Cu-O distances of 1.948 Å and Cu-N of 1.932 Å; the chelate O-Cu-N angle (average) is 94.0°. In the structures, the complexes are linked into dimeric associates with Cu…Cu distances of 3.197 Å (for 1) and 3.246 Å (for 2). The volatility of mixed-ligand complexes 1 and 2 is in between of that of the starting homo-ligand complexes.  相似文献   

10.
Heterocyclization of hydrazine with aldehydes R-CHO (R = Me, Et, Prn, Bun, n-C5H11, Ph, 4-MeOC6H4, 3-Py) and H2S leads to stereoisomeric 2,4,6,8-tetrasubstituted 3,7-dithia-1,5-diazabicyclo[3.3.0]octanes, which were separated by column chromatography. The trans-transoid-trans-configuration of tetramethyl(-ethyl,-propyl)-3,7-dithia-1,5-diazabicyclo-[3.3.0]octanes was inferred from the X-ray diffraction and 1H and 13C NMR spectroscopic data.  相似文献   

11.
A series of MVO(SO4)2 vanadium complexes, where M = Rb, Cs, or Tl, were prepared, and their crystal structures and physicochemical properties studied. The rubidium and thallium compounds of this series were found to be isostructural to each other and to crystallize, like KVO(SO4)2 and NH4VO(SO4)2, in orthorhombic system (space group P212121, No. 19, Z = 4) with the unit cell parameters a = 4.9735(2) Å, b=8.7894(4) Å, c = 16.6968(8) Å, V = 729.88 Å3 (Rb); and a = 4.9636(1) Å, b = 8.7399(2) Å, c = 16.8598(4) Å, V = 731.39 Å3 (Tl). The cesium compound was found to crystallize in monoclinic system (space group P21/a, No. 14-2, Z = 4): a = 10.0968(6) Å, b = 8.9131(4) Å, c = 9.8675(5) Å, β = 114.640(2)°, V = 807.16 Å3. The MVO(SO4)2 crystal structure is built of VO6 octahedra, which are linked into layers by bridging SO4 groups. At the apex of each VO6 octahedron, there is a short V-O terminal bond having a length of 1.54(1) Å (Rb), 1.57(2) Å (Tl), and 1.52(4) Å (Cs).  相似文献   

12.
The structures of all compounds were determined from three dimensional single crystal X-ray diffraction data and refined by least squares. Ba2CdS3 and Ba2CdSe3 are isostructural, Pnma, a = 8.9145(6)Å, b = 4.3356(2)Å, c = 17.2439(9)Å for the former compound and a = 9.2247Å, b = 4,4823(6)Å, c = 17.8706(11)Å for the latter, z = 4, R = 0.0751 and R = 0.0462, respectively. The compounds are isostructural with the previously reported Mn analogues and with K2AgI3. Cd ions are in tetrahedral environment and the tetrahedra form infinite linear chains by corner sharing. Ba ions are in 7-fold coordination in which 6 anions form a trigonal prism and 1 anion caps one of the rectangular faces. BaCdS2, Pnma, a = 7.2781(3)Å, b = 4.1670(1)Å, c = 13.9189(6)Å, z = 4, R = 0.0685. Cd ions can be considered to have a triangular planar coordination with CdS distances of 2.47 and 2.53 Å (twice). Two additional S ions are at 2.89 and 3.22 Å to complete a triangular bipyramidal configuration. Ba is in 7-fold coordination with the anions forming a trigonal prism which is capped on one rectangular face. The compound is isostructural with BaCdO2 and is related to the structure of BaMnS2. BaCdSe2 could not be prepared. BaCu2S2 and BaCu2Se2 are isostructural, Pnma, a = 9.3081(4)Å, b = 4.0612(3)Å, c = 10.4084(5)Å for the sulfide and a = 9.5944(6)Å, b = 4.2142(4)Å, c = 10.7748(8)Å for the selenide, z = 4, R = 0.0634 and 0.0373, respectively. Ba ions are in the usual 7-fold, capped hexagonal prism, coordination. However, 9 Cu ions also can be considered to form a trigonal prism with all rectangular faces capped, around Ba since the BaCu distances range from 3.24 to 3.54 Å for the sulfide and from 3.37 to 3.67 Å for the selenide. One of the Cu ions is in a very distorted tetrahedral environment and the second one is located in a more regular tetrahedral configuration of the anions. Two independent infinite chains of tetrahedra are present. They are formed by sharing of two adjacent edges of each tetrahedron and then these chains in turn are linked by corner sharing into a three-dimensional network of tetrahedra.  相似文献   

13.
Ammonium decamolybdodimetallates (NH4)n[M2Mo10O34(OH)4] · 7H2O, where M = Cr3+ (n = 6), Cu2+ (n = 8), or Ni2+ (n = 8), were synthesized for the first time and studied by X-ray diffraction, thermogravimetry, and IR spectroscopy. The compounds crystallize in the triclinic system with the following unit cell parameters: a = 10.68(2) Å, b = 9.46(2) Å, c = 7.97(2) Å, α = 75.12(3)°, β = 96.82(3)°, γ = 102.21(3)°, V = 754.4(3) Å3, ρcalcd = 4.05 g/cm3, Z = 1 for the chromium compound; and a = 10.57(2) Å, b = 9.29(2) Å, c = 8.47(2) Å, α = 73.91(3)°, β = 96.05(3)°, γ = 104.71(3)°, V = 854.3(3) Å3, ρcalcd = 3.68 g/cm3, Z = 1 (for the copper compound); and a = 10.96(2) Å, b = 8.95(2) Å, c = 7.40(2) Å, α = 71.76(3)°, β = 97.04(3)°, γ = 102.91(3)°, V = 875.3(3)Å3, ρcalcd = 3.65 g/cm3, Z = 1 for the nickel compound.  相似文献   

14.
Selective glycosylation of the 3-OH of 5,4′-di-O-acetyl-kaempferol was achieved with glycosyl ortho-alkynylbenzoates as donors under the catalysis of Ph3PAuNTf2, and subsequent glycosylation of the remaining 7-OH with glycosyl trifluoroacetimidates under the catalysis of BF3·OEt2, after global deprotection, afforded the kaempferol 3,7-O-bisglycosides conveniently.  相似文献   

15.
Interaction of salts of the cluster anions {Re [Re6Q8(CN)6]4?/3? (Q = Se, Te) with Nd salts in the presence of 2,2′-bipyridyl (Bipy) ligand brings about new coordination polymers: Pr 4 n N[{Nd(Bipy)(H2O)4} {Re6Se8(CN)6}] · 2H2O (I) (space group C2/c, a = 18.2918(16) Å, b = 14.9972(13) Å, c = 37.513(3) Å, β = 102.046(4)°, V = 10064.2(15) Å3, Z = 8), [{Nd(Bipy)2(H2O)} {Re6Se8(CN)6}] (II) (space group C2/c, a = 15.8668(3) Å, b = 13.5403(3) Å, c = 20.5189(4) Å, β = 110.135(1)°, V = 4138.89(15) Å3, Z = 4), and [{Nd(Bipy)(EtOH)(H2O)4}{Re6Te8(CN)6}] · EtOH (III) (space group $P\bar 1$ , a = 9.4733(6) Å, b = 12.5326(8) Å, c = 17.2374(11) Å, α = 96.561(2)°, β = 90.310(2)°, γ = 94.876(2)°, V = 4138.89(15) Å3, Z = 4). The compounds synthesized are characterized by single-crystal X-ray diffraction and IR methods. Compounds I and III have layered (2D) structures, compound II is a framework (3D) polymer.  相似文献   

16.
The crystal structure of the EuPrCuS3 complex sulfide synthesized for the first time has been solved by X-ray powder diffraction. Crystals are orthorhombic, space group Pnma. EuPrCuS3 has two polymorphs: the high-temperature phase of Ba2MnS3 structural type with unit cell parameters a = 8.0786(1) Å, b = 4.0288(1) Å, and c = 15.8389(2) Å and the low-temperature phase of BaLaCuS3-isostructural with unit cell parameters a = 11.0819(2) Å, b = 4.0710(1) Å, and c = 11.4459(3) Å.  相似文献   

17.
Anhydrous and partially hydrated acid trinuclear trifluoroacetates of divalent transition metals of the composition [M3(CF3COO)6(CF3COOH)6)](CF3COOH) and [M3(CF3COO)6(CF3COOH)2(H2O)4)](CF3COOH)2, respectively, where M = Co (I, III) Ni (II, IV), were synthesized and studied by X-ray diffraction. Complexes I and II were obtained by crystallization from solutions of M(CF3COO)2 · 4H2O in trifluoroacetic anhydride; complexes III and IV were synthesized under the same conditions with the use of 99% trifluoroacetic acid as a solvent. Crystals I are triclinic: space group $P\bar 1$ , a = 13.199(6) Å, b = 14.649(6) Å, c = 15.818(6) Å, α = 90.04(4)°, β = 114.32(4)°, γ = 108.55(4)°, V = 2611.3(19) Å3, Z = 2, R = 0.0480. Crystals II are trigonal: space group $R\bar 3$ , a = 13.307(2) Å, c = 53.13(1) Å, V = 8148(2) Å3, Z = 6, R = 0.1112. Crystals III are triclinic: space group $P\bar 1$ , a = 9.001(8) Å, b = 10.379(9) Å, c = 12.119(9) Å, α = 83.67(5)°, β = 72.33(5)°, γ = 83.44(5)°, V = 1068.3(15) Å3, Z = 1 Å, R = 0.1031. Crystals IV are triclinic: space group $P\bar 1$ , a = 9.121(18) Å, b = 10.379(2) Å, c = 12.109(2) Å, α = 84.59(3)°, β = 72.20(3)°, γ = 82.80(3)°, V = 1080.94(40) Å3, Z = 1, R = 0.0334.  相似文献   

18.
Single crystal X-ray diffraction study has been performed for heterometallic complexes based on lead(II) hexafluoroacetylacetonate and copper(II) β-diketonates. Crystal data for Cu(aa)2·Pb(hfa)2: a = 8.741(2) Å, b = 12.124(2) Å, c = 13.741(3) Å, α = 89.70(3)°, β = 89.50(3)°, γ = 75.06(3)°, space group P-1, Z = 2, d calc = 2.084 g/cm3; for Cu(hfa)2 Pb(hfa)2: a = 9.334(2) Å, b = 14.584(3) Å, c = 23.102(5) Å, β = 96.82(3)°, space group P21/c, Z = 4, d calc = 2.338 g/cm3. It is demonstrated that the principal structural motif for these compounds is a chain coordination polymer, which consists of alternating molecules of the complexes. The results of a thermogravimetric study for the compounds are reported.  相似文献   

19.
The (EnH2)[AuCl4]2·2H2O (I) and (EnH2)2[AuCl4]Cl3 (II) (EnH 2 2+ is diprotonated ethylenediamine) complexes are produced and characterized by elemental and thermogravimetric analysis, X-ray diffraction, IR and Raman spectroscopy. For I, the crystals are monoclinic, crystallize in the space group P21/c: a = 7.5870(2) Å, b = 9.5665(2) Å, c = 11.4706(3) Å, β = 107.0480(10)°, V = 795.97(3) Å3, Z = 4. For II, the crystals are orthorhombic, crystallize in the space group Pnma: a = 12.7088(3) Å, b = 17.7435(5) Å, c = 7.4992(2) Å, V = 1691.06(8) Å3, Z = 8.  相似文献   

20.
The crystal structure of [Eu(TTA)2(NO3)(TPPO)2] (I) (TTA = thenoyltrifluoroacetone, TPPO = triphenylphosphine oxide) possessing intense triboluminescence was established by X-ray crystallography. The crystals are triclinic, noncentrocymmetrical: a = 11.047(3) Å, b = 11.794(3) Å, c = 12.537(3) Å; α = 102.635 (4)°, β = 102.088(4)°,γ = 117.765(3)°; space group P1, Z = 1. The central Eu(III) atom coordinates two oxygen atoms of two TPPO molecules at distances of 2.271 Å and 2.282 Å, two oxygen atoms of the nitrate group at distances of 2.478 Å and 2.481 Å, four oxygen atoms of two TTA ions at distances of 2.365 Å, 2.381 Å, and 2.363 Å, 2.371 Å (coordination number is 8). The coordination polyhedron of the Eu(III) atom is a distorted dodecahedron. Possible reasons for spectral differences in the Stark structure of photo-and triboluminescence of I are discussed.  相似文献   

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