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1.
LaCl(BO2)2 and Er2Cl2[B2O5]: Two Chloride Oxoborates of Trivalent Lanthanides Er2Cl2[B2O5] is obtained as single crystals by the reaction of ErCl3, Er2O3 and B2O3 with an excess of ErCl3 as flux in evacuated silica tubes after two weeks at 850 °C. The compound crystallizes as long, pale pink needles and appears to be air‐ and water‐resistant. Single‐crystalline LaCl(BO2)2 emerges from the reaction of La2O3, LaCl3, and B2O3 with an excess of B2O3 as flux in evacuated silica tubes after four weeks at 900 °C. LaCl(BO2)2 crystallizes as thin, colourless, air‐ and water‐resistant needles which tend to severe twinning due to their fibrous habit. The crystal structure of Er2Cl2[B2O5] (orthorhombic, Pbam; a = 1489.65(9), b = 1004.80(6), c = 524.86(3) pm; Z = 4) contains two crystallographically different erbium cations. (Er1)3+ resides in pentagonal‐bipyramidal coordination of seven anions while (Er2)3+ is surrounded by only six anions with the shape of an octahedron. The planar oxodiborate units [B2O5]4— consisting of two vertex‐shared [BO3]3— triangles are isolated according to {([BOO]2)4—}. LaCl(BO2)2 crystallizes isostructurally with PrCl(BO2)2 in the triclinic space group P1¯ (a = 423.52(4), b = 662.16(7), c = 819.33(8) pm; α = 82.081(8), β = 89.238(9), γ = 72.109(7)°; Z = 2). The characteristic unit consists of endless chains built up by corner‐linked [BO3]3— triangles. These quasi‐planar zigzag chains of the composition {[(B1)OO(B2)OO]2—} (≡ {[BO2]} run parallel [100]. The La3+ cations exhibit coordination numbers of ten and are coordinated by three Cl and seven O2— anions.  相似文献   

2.
Iodostannates with Polymeric Anions: (Me3PhN)4 [Sn3I10], [Me2HN–(CH2)2–NMe2H]2 [Sn3I10], and [Me2HN–(CH2)2–NMe2H] [Sn3I8] The polymeric iodostannate anions in (Me3PhN)4 [Sn3I10] ( 1 ) and [Me2HN–(CH2)2–NMe2H]2 [Sn3I10] ( 2 ) consist of Sn3I12‐trioctahedra, which share four common iodine atoms with adjacent units to form infinite layers in 1 and polymeric chains in 2 . In the anion of [Me2HN–(CH2)2–NMe2H] [Sn3I8] ( 3 ) distorted SnI6 octahedra sharing common edges and vertices form a two‐dimensional network. (Me3PhN)4 [Sn3I10] ( 1 ): Space group C2/c (No. 15), a = 2406.9(2), b = 968.26(7), c = 2651.7(2) pm, β = 111.775(9), V = 5738.9(8) · 106 pm3; [Me2HN–(CH2)2–NMe2H]2 [Sn3I10] ( 2 ): Space group P21/n (No. 14), a = 1187.2(1), b = 1554.4(1), c = 1188.9(1) pm, β = 116.620(8), V = 1961.4(3) · 106 pm3; [Me2HN–(CH2)2–NMe2H] [Sn3I8] ( 3 ): Space group P21/c (No. 14), a = 1098.9(2), b = 803.93(7), c = 1571.5(2) pm, β = 102.96(1), V = 1352.9(2) · 106 pm3.  相似文献   

3.
On a New Copper Tin Borate Oxide with Isolated BO3 Units: Cu5Sn(BO3)2O4 Single Crystals of the new compound Cu5Sn(BO3)2O4 were obtained by a B2O3 fluxtechnique. They crystallize in a monoclinic distorted variant of a Ludwigite structure with a partly ordered metal distribution. X-ray investigations on single crystals led to the space group C–P21/c (No. 14); a = 6.3526(7); b = 9.502(1); c = 12.100(9) Å; β = 93.30(3)°; Z = 4. All metal-sites are distorted octahedraly coordinated by oxygen-ions. The structure contains BO3-units and oxygen which is not coordinated to boron.  相似文献   

4.
The kinetics of a net two‐electron transfer between an authentic MnIV complex, [Mn(bigH)3]4+ (Fig. 1; bigH = biguanide = C2N5H7), and nitrite in aqueous solution in the pH interval 2.00–3.60 is described. Stoichiometric data for the reaction clearly indicates Δ[MnIV]/Δ[NIII]T = 1.07 ± 0.10, and is detected as the oxidized product of nitrite ([NIII]T = [HNO2] + [ ]). Though both HNO2 and are found to be reactive, the latter is kinetically superior in reducing the fully protonated MnIV complex. Proton‐coupled electron transfer (PCET; 1e, 1H+) reduces the activation barrier for the thermodynamically unfavorable reaction of weakly oxidizing MnIV species. At the end of the redox process, the ligand bigH is released, and the high protonation constants of the ligand carry the overall reaction to completion.  相似文献   

5.
Synthesis and Crystal Structure of Terbium(III) meta‐Oxoborate Tb(BO2)3 (≡ TbB3O6) The terbium meta‐oxoborate Tb(BO2)3 (≡ TbB3O6) is obtained as single crystals by the reaction of terbium, Tb4O7 and TbCl3 with an excess of B2O3 in gastight sealed platinum ampoules at 950 °C after three weeks. The compound appears to be air‐ and water‐resistant and crystallizes as long, thin, colourless needles which tend to growth‐twinning due to their marked fibrous habit. The crystal structure of Tb(BO2)3 (orthorhombic, Pnma; a = 1598.97(9), b = 741.39(4), c = 1229.58(7) pm; Z = 16) contains strongly corrugated oxoborate layers {(BO2)} built of vertex‐linked [BO4]5‐ tetrahedra (d(B‐O) = 143 ‐ 154 pm, ?(O‐B‐O) = 102‐115°) which spread out parallel (100). The four crystallographically different Tb3+ cations all exhibit coordination numbers of eight towards the oxygen atoms (d(Tb‐O) = 228‐287 pm). The corresponding metal cation polyhedra [TbO8]13+ too convene to layers (composition: {(Tb2O11)16‐}) which are likewise oriented parallel to the (100) plane.  相似文献   

6.
Transition Metal‐substituted Phosphaalkenes. 42 Reactivity of the Ferriophosphaalkenes [(η5‐C5Me5)(CO)2FeP=C(NR )R2] (NR = NMe2, NC5H10, R2 = Ph, t Bu) towards Protic Acids, Alkylation Reagents, and [{( Z )‐Cyclooctene}Cr(CO)5] The reaction of equimolar amounts of [(η5‐C5Me5)(CO)2FeP=C(NR )R2] ( 2 a : NR = NMe2, R2 = Ph; 2 b : NMe2. tBu; 2 c : NC5H10, Ph) and etherial HBF4 gave rise to the formation of [(η5‐C5Me5)(CO)2FeP(H)C(NR )R2] (BF4) ( 3 a – c ) which were isolated as light red powders. Compounds 2 a – c were converted into [(η5‐C5Me5)(CO)2FeP(Me)C(NR )R2] (SO3CF3) ( 4 a – c ) by treatment with methyl trifluoromethane sulfonate. In addition 2 a and Me3SiCH2OSO2CF3 afforded light red [(η5‐C5Me5)(CO)2FeP(CH2SiMe3)C(NMe2)Ph](SO3CF3) ( 5 ). The black complex [(η5‐C5Me5)(CO)2FeP{Cr(CO)5}C(NMe2)Ph] ( 6 ) resulted from the combination of 2 a with [{(Z)‐cyclooctene}Cr(CO)5]. The novel products were characterized by elemental analyses and spectra (IR, 1H‐, 13C‐ und 31P‐NMR).  相似文献   

7.
Aqueous iodination of trans-2-butenoic acid proceeds via hydrolysis of I2 to form HOI and I?, then rapid addition of HOI across the double bond to form the iodohydrin product. In the presence of iodate to keep iodide concentration low, the reaction proceeds at a conveniently measurable rate. The rate for the addition reaction is ?d[C4H6O2]/dt = 5900 [H+][C4H6O2][HOI]M/s at 25.0°C when [IO] = 0.025M and ionic strength = 0.3. The overall rate law in the presence of iodate is where [H+] and [IO] are total concentrations used to prepare the solution.  相似文献   

8.
9.
Tetraammine Lithium Cations Stabilizing Phenylsubstituted Zintl-Anions: The Compound [Li(NH3)4]2[Sn2Ph4] Ruby-red, brittle single crystals of [Li(NH3)4]2[Sn2Ph4] were synthesized by the reaction of diphenyltin dichloride and metallic lithium in liquid ammonia at ?35°C. The structure was determined from X-ray singlecrystal diffractometer data: Space group, P1 , Z = 1, a = 9.462(2) Å, b = 9.727(2) Å, c = 11.232(2) Å, α = 66.22(3)°, β = 85.78(3)°, γ = 61.83(3)°, R1 (F ? 4σF) = 5.13%, wR2 (F02 ? 4σF) = 10.5%, N(F ? 4σF) = 779, N(Var.) = 163. The compound contains to Sb2Ph4 isosteric centres [Sn2Ph4]2? as anions which are connected to rods by lithium cations in distorted tetrahedral coordination by ammonia. These rods are arranged parallel to one another in the b,c-plane, but stacked along [100].  相似文献   

10.
The Crystal Structure of Cu2M(BO3)O2 (M = Fe3+, Ga3+) Single Crystals of the compounds Cu2M(BO3)O2 (M = Fe3+ (I), Ga3+ (II)) were obtained by a B2O3 flux-technique. They crystallize in a monoclinic distorted variant of a Ludwigite structure with a partly ordered metal distribution. X-ray investigations on single crystals led to the space group C–P21/c (No. 14); I: a = 3.108(1); b = 12.003(1); c = 9.459(3) Å; b? = 96.66(3)°; Z = 4 and II: a = 3.1146(2); b = 11.921(3); c = 9.477(2) Å; b? = 97.91(2)°; Z = 4. All metal-sites are distorted octahedraly coordinated by oxygen-ions. The structure contains isolated planar BO3-units and oxygen which is not coordinated to boron.  相似文献   

11.
Oxygentation of aqueous solutions of CoIII in presence of stoichiometric amounts of N-(2-aminoethyl)ethane-1,2-diamine (dien) and 1,3-diaminopropan-2-ol (dapo) produces μ-peroxocobalt(III) dimers. Acid cleavage (HCI) yields mer-exo(H)-, mer-endo (H)-, unsym-fac-exo(OH)-, and unsym-fac-endo(OH)-[CoCl(dien)(dapo)]2+ ( A–D )(X = Cl), resp. and unsym-fac-[Co-(dien)(dapo-N,N′,O)]3+ ( G ). Isomer seperation was achieved by fractional crystallization as ZnCl and ClO salts and by ion-exchange chromatography. The corresponding bromo, azido, nitrito-O, nitro-N, thiocyanato, hydroxo, and aqua complexes were also synthesized. Optically resolved samples were prepared for chiral compounds, and the complexes were structurally characterized by X-ray analyses ($ \mathop {\it \Lambda} \limits^ \to $(?)436(CD) -A (X = N3)), ($ \mathop {\it \Delta} \limits^ \to $(?)436(CD) -B ). (X = N3), $ \mathop {\it \Delta} \limits^ \to $ (+)436(CD) -B by their chiroptical properties, and by 13C-NMR spectroscopy supported by 1H-NMR, IR, CD, and UV/VIS spectroscopy. $ \mathop {\it \Lambda} \limits^ \to $(?)436(CD)-mer-exo(H)-[Co(N3)(dien)(dapo)](hydrogen di-O-benzoyl-L-tartrate)2.4 H2O crystallizes in the orthorhombic space group P212121, a = 7.676(1) Å, b = 19.457(1) Å, c = 34.702(2) Å. $ \mathop {\it \Lambda} \limits^ \to $(?)436(CD)-mer-endo(H)-[Co(N3)(dien)(dapo)] (hydrogen di-O-benzoyl-L-tartrate)2.2.75 H2O crystallizes in the triclinic space group P1, a = 8.062(3) Å b = 10.296(1) Å, c = 15.056(2) Å, alpha = 80.55(1)°, β = 85.18(2)°, γ = 89.10(2)°. $ \mathop {\it \Delta} \limits^ \to $(+)436(CD)-mer-endo(H)-[Co(N3)(dien)(dapo)](hydrogen di-O-benzoyl-L-tartrate)2. 5.75 H2O crystallizes in the triclinic space group P1, a = 7.742(1) Å, b = 10.014(1) Å, c = 18.045(2) Å, α = 99.57(1)°, β = 92.87(1)°, γ = 102.56(1)°. The absolute configurations of the three cations were determined unambiguously. Interconversions of the various isomers and derivatives and structural, configurational, and spectroscopic aspects are discussed in detail.  相似文献   

12.
Single Crystals of the Cerium(IV) Oxotellurate(IV) CeTe2O6 Orange‐red, coffin‐shaped single crystals of CeTe2O6 (monoclinic, P21/n; a = 703.71(5), b = 1106.32(8), c = 735.24(5) pm, β = 108.066(6)°; Z = 4) were obtained by the reaction of admixtures of cerium dioxide and tellurium dioxide (CeO2, TeO2; molar ratio 1 : 2) in the presence of fluxing CsCl (750 °C, 4 d) in evacuated silica tubes. The crystal structure contains eightfold coordinated Ce4+ cations, which are surrounded by irregular trigonal dodecahedra of oxygen atoms. The interconnection of these [CeO8] polyhedra occurs via two edges (O2–O2′ and O3–O3′) with equatorial orientation relative to each other forming zigzag chains {[CeO4/1O4/2]8–} which run parallel to [100] and arrange as a hexagonal packing of rods. Both crystallographically different Te4+ cations exhibit trigonal non‐planar coordination figures (ψ1 tetrahedra) with three oxygen atoms each as a result of the stereochemical activity of the non‐binding electron pairs (“lone pairs”). They also are responsible for the necessary cross‐linkage of the anionic {[CeO6]8–} chains. The isotypical relationship with Ce(SeO3)2 therefore justifies the formulation Ce(TeO3)2 for CeTe2O6.  相似文献   

13.
Iodostannates(II) with Anionic [SnI3] Chains – the Transition from Five to Six‐coordinated SnII The iodostannates (Me4N) [SnI3] ( 1 ), [Et3N–(CH2)4–NEt3] [SnI3]2 ( 2 ), [EtMe2N–(CH2)2–NEtMe2] [SnI3]2 ( 3 ), [Me2HN–(CH2)2–NH–(CH2)2–NMe2H] [SnI3]2 ( 4 ), [Et3N–(CH2)6–NEt3] [SnI3]2 ( 5 ) and [Pr3N–(CH2)4–NPr3]‐ [SnI3]2 · 2 DMF ( 6 ) with the same composition of the anionic [SnI3] chains show differences in the coordination of the SnII central atoms. Whereas the Sn atoms in 1 and 2 are coordinated in an approximately regular octahedral fashion, in compounds 3 – 6 the continuous transition to coordination number five in (Pr4N) [SnI3] ( 7 ) or [Fe(dmf)6] [SnI3]2 ( 8 ) can be observed. Together with the shortening of two or three Sn–I bonds, the bonds in trans position are elongated. Thus weak, long‐range Sn…I interactions complete the distorted octahedral environment of SnI4 groups in 3 and 4 and SnI3 groups in 5 and 6 . Obviously the shape, size and charge of the counterions and the related cation‐anion interactions are responsible for the variants in structure and distortion.  相似文献   

14.
The structures of [Pd(η3‐C3H5)(HpzR2)2](BF4) (HpzR2=Hpzbp2=3,5‐bis(4‐butoxyphenyl)‐1H‐pyrazole, 1 ; HpzR2=HpzNO2=3,5‐dimethyl‐4‐nitro‐1H‐pyrazole=Hdmnpz, 2 ) and [Ag(HpzR2)2](A) (HpzR2=Hpzbp2, A= , 3 ; HpzR2=HpzNO2, A= , 4 ) were comparatively analyzed to determine the factors responsible for polymeric assemblies. In all cases, the H‐bonding interactions between the pyrazole moieties and the appropriate counterion and, in particular, the orientation of the NH groups of the pyrazole ligands are determinant of one‐dimensional polymeric arrays. In this context, the new compound [Ag(HpzNO2)2](NO3) ( 5 ) was synthesized and its structure analyzed by X‐ray diffraction (Fig. 4). The HpzNO2 serves as N‐monodentate ligand, which coordinates to the AgI center through its pyrazole N‐atom giving rise to an almost linear N Ag N geometry. The planar NO counterion bridges two adjacent AgI centers to form a one‐dimensional zigzag‐shaped chain which is also supported by the presence of N H⋅⋅⋅O bonds between the pyrazole NH group of adjacent cationic entities and the remaining O‐atom of the bridging NO (Fig. 5). The chains are further extended to a two‐dimensional layer‐like structure through additional Ag⋅⋅⋅O interactions involving the NO2 substituents at the pyrazole ligands (Fig. 6).  相似文献   

15.
Rb2Co3(H2O)2[B4P6O24(OH)2]: A Borophosphate with ‐Tetrahedral Anionic Partial Structure and Trimers of Octahedra (Co O12(H2O)2) Rb2Co3(H2O)2[B4P6O24(OH)2] is formed under mild hydrothermal conditions (T = 165 °C) from mixtures of RbOH(aq), CoCl2, H3BO3, and H3PO4 (molar ratio 1 : 1 : 1 : 2). The crystal structure (orthorhombic system) was solved by X‐ray single crystal methods (space group Pbca, No. 61; R‐values (all data): R1 = 0.0699, wR2 = 0.0878): a = 950.1(1) pm, b = 1227.2(2) pm, c = 2007.4(2) pm; Z = 4. The anionic partial structure consists of tetrahedral [B4P6O24(OH)28–] layers, which contain three‐ and nine‐membered rings. CoII is octahedrally coordinated by oxygen and oxygen and H2O ligands, respectively (coordination octahedra CoO6 and CoO4(H2O)2). Three adjacent coordination octahedra are condensed via common edges to form trimeric units (CoO12(H2O)2). The oxidation state +2 of cobalt was confirmed by magnetic measurements. The octahedral trimers are quasi‐isolated. No long‐range magnetic ordering occurs down to 2 K. Rb+ is disordered over three crystallographically independent sites within channels of the structure running parallel [010]; the coordination sphere of Rb+ is formed by nine oxygen species of the tetrahedral layers, one OH group and one H2O molecule.  相似文献   

16.
Preparation and Crystal Structure of BaLi[BO3] For the first time colourless lamellar single crystals of BaLi[BO3] have been prepared from intimate mixtures of BaO2, Li2O and B2O3. The structure determination from four-circle diffractometer data (MoKα , 882 independent reflections, R = 2.4%, Rw = 1.9%) confirms the space group P 21/c with Z = 4; a = 646.1(3), b = 710.7(2), c = 740.3(3) pm, β = 117.99(3)°. Characteristic units of the structure are layers {Li[BO3]} parallel to (100) consisting of trigonal planar [BO3] groups and distorted [LiO5] pyramids. Effective Coordination Numbers (ECoN), Mean Fictive Ionic Radii (MEFIR), the Madelung Part of Lattice Energy (MAPLE) and the Charge Distribution (CHARDI) are calculated and discussed.  相似文献   

17.
On the Reactivity of the Ferriophosphaalkene (Z)‐[Cp*(CO)2Fe‐P=C(tBu)NMe2] towards Propiolates HC≡C‐CO2R (R=Me, Et) and Acetylene Dicarboxylates RO 2C‐C≡C‐CO2R (R=Me, Et, tBu) The reaction of equimolar amounts of (Z)‐[Cp*(CO)2Fe‐P=C(tBu)NMe2] 3 and methyl‐ and ethyl‐propiolate ( 2a, b ) or of 3 and dialkyl acetylene dicarboxylates 1a (R=Me), 1b (Et), 1c (tBu) afforded the five‐membered metallaheterocycles [Cp*(CO) =C(tBu)NMe2] ( 4a, b ) and [Cp*(CO) =C(tBu)NMe2] ( 5a—c ). The molecular structures of 4b and 5a were elucidated by single crystal X‐ray analyses. Moreover, the reactivity of 4b towards ethereal HBF4 was investigated.  相似文献   

18.
Synthesis and Structure of the First Ternary Lead(II) Copper(I) Oxide: PbCu2O2 PbCu2O2 can be prepared by solid state reaction or by precipitation from a basic aqueous solution. Single crystals of the new compound were prepared by recrystallisation from a molten mixture (PbO? Cu2O) and investigated by X-ray diffractometer technique. PbCu2O2 crystallizes isotypically with the homologue silver compound PbAg2O2 (monoclinic with a = 8.223 Å, b = 8.289 Å, c = 6.015 Å, β = 132.62°, Z = 4, space group C? C 1 2/c 1). The crystallographic data from the X-ray investigation are reported. The structure is built by endless [PbO4/4]- and [CuO2/4]-chains. Pb2+ has a one-sided asymmetric coordination with four next oxygen neighbours and Cu+ forms a stretched dumbbell with two oxygen atoms.  相似文献   

19.
(C2H10N2)[BPO4F2] — Strukturbeziehungen zwischen [BPO4F2]2— und [Si2O6]4— Colourless crystals of (C2H10N2)[BPO4F2] were prepared from mixture of ethylendiamine, H3BO3, BF3 · C2H5NH2, H3PO4 and HCl under mild hydrothermal conditions (220 °C). The crystal structure was determined by single crystal methods (triclinic, P1¯ (no. 2), a = 451.85(5) pm, b = 710.20(8) pm, c = 1210.2(2) pm, α = 86.08(1)°, β = 88.52(2)°, γ = 71.74(1)°, Z = 2) and contains infinite tetrahedral zweier‐single‐chains {[BPO4F2]2—} which are isoelectronic (48e) with the polyanions {[Si2O6]4—} of the pyroxene family.  相似文献   

20.
Liquid secondary ion mass spectra of choline and acetylcholine halides exhibit several series of cluster ions whose origins were investigated using B/E and B2/E linked-scan techniques. In the case of choline halides three series of cluster ions were identified as (Me3$ \mathop {\rm N}\limits^ + $CH2CH2OH + nM), (Me3$ \mathop {\rm N}\limits^ + $CH2CH2OMe + nM) and (Me3N$ \mathop {\rm N}\limits^ + $CH2CH2OH · Me3$ \mathop {\rm N}\limits^ + $CH2CH2O? + nM), while (CH3COOCH2CH2$ \mathop {\rm N}\limits^ + $Me3 + nM), (Me3$ \mathop {\rm N}\limits^ + $CH2CH2OH + nM) and (CH2 = CH$ \mathop {\rm N}\limits^ + $Me3 + nM) were observed in the spectra of acetylcholine halides. For these cluster ions, bimolecular reactions induced on ion bombardment under secondary ion mass spectrometric conditions are discussed.  相似文献   

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