Bildung und NMR-spektroskopische Charakterisierung von Alk-(ar-)oxyderivaten von Trichlorphosphazen-N-phosphoryldichlorid,Cl3PN?P(O)Cl2, Imido- und N-Methylimidodiphosphoryltetrachlord,Cl2P(O)NHP(O)Cl2 bzw. Cl2P(O)N(CH3)P(O)Cl2

Formation and N.M.R.-Spectroscopic Characterization of Alk-(ar-)oxy Derivatives of Trichlorophosphazene-N-phosphoryldichloride, Cl₃P?N? P(O)Cl₂, Imido- and N-Methylimidodiphosphoryltetrachloride, Cl₂P(O)NHP(O)Cl₂ and Cl₂P(O)N(CH₃)P(O)Cl₂ The ester chlorides and esters P₂NOCl_5?x(OR)_x (x = 1?5), P₂(NH)O₂Cl_4?x(OR)_x (x = 1–4) and P₂(NCH₃)O₂Cl_4–x(OR)_x (x = 1–4) derived from the title compounds by substitution of chlorine atoms by alk- or aroxy groups are characterized by their ³¹P-n.m.r. data. The possibilities for forming these compounds by alcoholysis, chloridolysis, dealkylation and P? N-bond formation are discussed.     

Mo2O3Cl4(Pyridin)4 · CH2Cl2 Synthese,IR-Spektrum und Kristallstruktur

Mo₂O₃Cl₄(Pyridine)₄ · CH₂Cl₂. Synthesis, IR Spectrum, and Crystal Structure Reduction of MoO₂Cl₂(pyridine)₂ with triphenylphosphane in toluene and recrystallisation from CH₂Cl₂ yields brown crystal needles of the complex Mo₂O₃Cl₄(pyridine)₄ · CH₂Cl₂. The compound crystallizes monoclinic in the space group P2₁/c with four formula units per unit cell of the dimensions a = 1 234.6 pm; b = 1 593 pm, c = 1 522.3 pm and β = 105.66° A structural investigation by X-ray methods (3 276 independent observed reflexions, R = 0.033) reveals the molecule with two molybdenum atoms in a distorted octahedral coordination linked by an almost linear Mo? O? Mo bridge with bond distances of 167 and 168 pm, respectively. The chlorine atoms are located in trans-position to the oxygen atoms which have different trans effects: The Mo? Cl bond opposite the bridge (length 242 pm) is 8 pm shorter than the bond in trans position to the terminal oxo ligands. The pyridine nitrogen atoms are in trans position to each other and complete the coordination of the molybdenum atoms. The i.r. spectrum of the compound is reported.     

Reactions of trialkylalanes with cyclic acetals and orthoformates in CH2Cl2 and ClCH2CH2Cl as solvents

Under mild conditions, trialkylalanes (Et₃Al and Buⁱ ₃Al) in chlorine-containing solvents (CH₂Cl₂ or ClCH₂CH₂Cl) react with cyclic acetals and orthoformates to form glycol monoethers and dialkylacetals, respectively, in high yields. The ¹H NMR spectroscopic data demonstrate that CH₂Cl₂ or ClCH₂CH₂Cl interacts with Buⁱ ₃Al.     

Darstellung und Eigenschaften von Tris-(β-chloräthyl) phosphinoxid und Bis-(β-chloräthyl)-(chlormethyl)-phosphinoxid. 43. Mitteilung über organische Phosphorverbindungen [1]

The oxidative degradation of [(HOCH₂CH₂)₃PCH₂OH]⁺Cl^? ( 1 ) with Cl₂ yields, dependent on the pH used, either (HOCH₂CH₂)₃P?O ( 2 ) or (HOCH₂CH₂)₂ (HOCH₂) P?O ( 3 ). Chlorination of 2 and 3 with PCl₅ produces the corresponding chlorides (ClCH₂CH₂)₃P?O ( 4 ) and (ClCH₂CH₂)₂ (ClCH₂)P?O ( 5 ), respectively. Acetylation of 2 and 3 gives the corresponding esters (CH₃CO₂CH₂CH₂)₃P?O ( 6 ), and (CH₃CO₂CH₂CH₂)₂ (CH₃CO₂CH₂)P?O ( 7 ), respectively. Reaction of 7 with HBr results in the formation of (BrCH₂CH₂)₂ (BrCH₂)P?O. Nucleophilic substitution of the chlorine atoms in 4 and 5 with alkoxide or mercaptide gives e.g., 9 , 10 , 11 or 11a , while treatment with tertiary amines yields the vinyl compounds (CH₂?CH)₃P?O ( 12 ) and (CH₂?CH)₂ (CH₂Cl)P?O ( 13 ). 4 and 5 also undergo an Arbuzov type reaction with tertiary phosphites to give 14 and 15 , respectively, which on hydrolysis with conc. HCl give the corresponding acids 16 and 17 , respectively.     

Nitrosylkomplexe des Molybdän(+II) Die Kristallstrukturen von [Mo(NO)Cl3 · POCl3]2 und von [AsPh4]2[Mo(NO)Cl5] · 2 CH2Cl2

Nitrosyl Complexes of Molybdenum (+II). Crystal Structures of [Mo(NO)Cl₃ · POCl₃]₂ and [AsPh₄]₂[Mo(NO)Cl₅] · 2 CH₂Cl₂ Solutions of MoCl₅ in POCl₃ react with NOCl forming the nitrosyl compound Mo(NO)Cl₃ · 2POCl₃ ( I ), which in CH₂Cl₂ cleaves off one solvate molecule, yielding the dimeric complex [Mo(NO)Cl₃ · POCl₃]₂ ( II ). Reaction with AsPh₄Cl in dichloro methane leads to the nitrosyl complexes AsPh₄[Mo(NO)Cl₄] · CH₂Cl₂ ( III ) and [AsPh₄]₂[Mo(NO)Cl₅] · 2CH₂Cl₂ ( IV ), respectively. The i.r. spectra are recorded and assigned. [Mo(NO)Cl₃ · POCl₃]₂ crystallizes monoclinic in the space group P2₁/c with two dimeric units per unit cell. The crystal structure was determined by X-ray diffraction methods (R = 0.040; 1391 observed, independent reflexions). Complex II is linked by chlorine bridges, forming a dimeric, centrosymmetric molecule of symmetry C_i. The N? O bond of the nitrosyl ligand is extremely short (108 pm), the Mo? N bond (181 pm) corresponds to a double bond. In trans position to the NO ligand, which is coordinated in linear array, there is the O atom of the solvate molecule POCl₃. [AsPh₄]₂[Mo(NO)Cl₅] · 2 CH₂Cl₂ crystallizes triclinic in the space group P1 with two units per unit cell (R = 0.039; 1967 observed, independent reflexions). The molybdenum atom is coordinated octahedrally by five Cl ligands and a nitrosyl group, as well coordinated in linear array (Mo? N? O 174°). The nitrosyl ligand exerts a significant trans-effect (r Mo? Cl_(trans) = 247 pm, r MoCl_4(eq)(average) = 239 pm).     

Darstellung,spektroskopische Untersuchungen und Kristallstruktur von [Cl4SbO2P(CH3)2]2

Preparation, Spectroscopic and Crystal Structure Investigations of [Cl₄SbO₂P(CH₃)₂]₂ [Cl₄SbO₂P(CH₃)₂]₂ was prepared from SbCl₅ and HOP(O)(CH₃)₂ in CH₂Cl₂. The compound crystallizes in the space group P2₁/n with two dimeric units per unit cell; the lattice constants are a = 875, b = 1306, c = 923 pm and β 97.1°. Structural investigation by X-ray diffraction methods showed the Sb atoms in the dimeric units to be linked by O? P? O-bridges of the dimethylphosphinate groups to Sb₂O₄P₂ eight-rings of approximate symmetry C_2h. The vibrational spectrum (i.r., Raman) and the n.m.r. spectra (³¹P, ¹H) consist with this structure.     

Die Kristallstrukturen von (Ph4P)2[HfCl6]·2CH2Cl2 und (Ph4P)2[Hf2Cl10]·CH2Cl2

Crystal Structures of (Ph₄P)₂[HfCl₆]·2CH₂Cl₂ and (Ph₄P)₂[Hf₂Cl₁₀]·CH₂Cl₂ Colourless single crystals of (Ph₄P)₂[HfCl₆]·2CH₂Cl₂ ( 1 ) and (Ph₄P)₂[Hf₂Cl₁₀]·CH₂Cl₂ ( 2 ) were obtained from hafniumtetrachloride and tetraphenylphosphonium chloride in dichloromethane solution, using the corresponding stoichiometry of the educts. Both compounds were characterized by X‐ray structure determinations. 1 : Space group P1¯, Z = 1, lattice dimensions at 193 K: a = 1018.3(1), b = 1121.0(1), c = 1240.1(1) pm, α = 70.55(1)°, β = 81.38(1)°, γ = 80.02(1)°, R₁ = 0.0374. 2 : Space group P1¯, Z = 1, lattice dimensions at 193 K: a = 1124.4(1), b = 1141.9(1), c = 1281.4(1) pm, α = 63.80(1)°, β = 68.15(1)°, γ = 86.33(1)°, R₁ = 0.0208.     

Attempted Abstraction of the Halogenides in (HNEt3)[Re(CH3CN)2Cl4] and Crystal Structures of cis‐[Re(CH3CN)2Cl4]·CH3CN and cis‐[Re(NHC(OCH3)CH3)2Cl4]

The abstraction of the halogenide ligands in [Re(CH₃CN)₂Cl₄]^? should result in a solvent‐only stabilized Re^III complex. The reactions of salts of [Re(CH₃CN)₂Cl₄]^? with silver(I) and thallium(I) salts were investigated and the solid‐state structures of cis‐[Re(CH₃CN)₂Cl₄]·CH₃CN and cis‐[Re(NHC(OCH₃)CH₃)₂Cl₄] are described.     

Organische Phosphorverbindungen 44 Darstellung und Eigenschaften von Bis-(ß-chloräthyl)-phosphinsäure-Derivaten [1]

Reaction of ClCH₂CH₂PCl₂ with ethylene oxide gives the phosphonous acid ester ClCH₂CH₂P (OCH₂CH₂Cl)₂ which on heating to 120° rearranges to the phosphinic acid ester (ClCH₂CH₂)₂P(O)OCH₂CH₂Cl ( 3 ). Chlorination of 3 with PCl₅ in CCl₄-solution yields the phosphinic chloride (ClCH₂CH₂)P(O)Cl ( 4 ), which on treatment with P₂S₅ at 170° produces the thioderivative, (ClCH₂CH₂)₂P(S)Cl, (₅). Treatment of 4 and 5 with alcohols, mercaptanes, or amines in the presence of an acid binding agent leads to the corresponding phosphinic and thiophosphinic acid derivatives, (ClCH₂CH₂) P (X)Y, (X = O, S; Y = OR, SR, NR₂) ( 6 ). Reaction of 6 with excess base yields the corresponding divinylphosphinic and divinylthiophosphinic acid derivatives (CH₂ = CH)₂P (X) Y (X = O, S; Y = OR, SR, NR₂) ( 7 ). Bis-(ß-chloroethyl)-phosphinates, e. g. (ClCH₂CH₂)₂P (O) OEt, undergo a Michaelis-Arbuzov reaction when heated with phosphites to 160–170° to give bis-(phosphonylethyl)-phosphinates, e.g. (EtO) (O)P[CH₂CH₂CH₂P(O)(OEt)₂]₂ ( 8 ), which on hydrolysis with conc. HCl under reflux yield the corresponding acid HO₂P(CH₂CH₂PO₃H₂)₂.     

(PPh4)2[WO2Cl3]2 · 2 CH2Cl2: Synthese,Schwingungsspektrum und Kristallstruktur

(PPh₄)₂[WO₂Cl₃]₂ · 2 CH₂Cl₂. Synthesis, Vibrational Spectrum, and Crystal Structure Depending on the stoichiometry and the solvent, dichloromethane or 1.2-dichloroethane, WO₂Cl₂ reacts with tetraphenylphosphonium chloride affording (PPh₄)₂[WO₂Cl₄] or (PPh₄)₂[WO₂Cl₃]₂, respectively. Both compounds are easily soluble in dichloromethane, from which they can be crystallized under incorporation of two molecules CH₂Cl₂ per formula unit. The crystalline compounds have been characterized by their IR and Raman spectra. According to the X-ray crystal structure analysis, (PPh₄)₂[WO₂Cl₃]₂ · 2 CH₂Cl₂ crystallizes in the triclinic space group P1 with one formula unit per unit cell (986 independent observed reflexions, R = 0.061). Lattice constants: a = 1100.2, b = 1116.9, c = 1238.4 pm, = 69.40, = 80.46 and = 85.62°. The crystals consist of PPh₄^⊕ ions, centrosymmetric [WO₂Cl₃]₂^2? anions and CH₂Cl₂ molecules. In the anions, the tungsten atoms are linked via two oxo bridges with WO distances of 184 and 252 pm. The distorted octahedral coordination around each tungsten atom is completed by three terminal chloro and one terminal oxo ligand (WO bond length 166 pm), the latter being in trans position to the longer WO bridging bond. (PPh₄)₂[WO₂Cl₄] · 2 CH₂Cl₂ also forms triclinic crystals that are isotypic with (PPh₄)₂[WOCl₅] · 2 CH₂Cl₂ and in which the anions must have orientational disorder.     

Schwingungsspektren und Kraftkonstanten von Cl3SiP(CH3)2 und Cl3SiAs(CH3)2

Vibrational Spectra and Force Constants of Cl₃SiP(CH₃)₂ and Cl₃SiAs (CH₃)₂ The i.r. and Raman spectra of Cl₃SiP(CH₃)₂ and Cl₃SiAs (CH₃)₂ have been recorded and assigned. A normal coordinate analysis has been made using a modified valence force field. The SiP force constant is slightly higher than those of alkylsilylphosphines, whereas a similar effect is not found for the SiAs bond.     

4-Methyl-1,2,3,5-dithiadiazoliumsalze Die Kristallstrukturen von (CH3CN2S2)5[CoCl4]Cl3 und (CH3CN2S2)Cl

4-Methyl-1,2,3,5-dithiadiazolium Salts. Crystal Structures of(CH₃CN₂S₂)₅[CoCl₄]Cl₃ and (CH₃CN₂S₂)Cl 4-Methyl-1,2,3,5-dithiadiazolium tetrachlorocobaltate trichloride, (CH₃CN₂S₂)₅[CoCl₄]Cl₃, was obtained by reaction of trithiazyl chloride, (NSCl)₃, with CoCl₂ in acetonitrile; it forms brown, moisture sensitive crystals. With tetraphenylarsonium chloride in CH₂Cl₂ it yields yellow crystalline (CH₃CN₂S₂)Cl and (AsPh₄)₂CoCl₄. The IR spectra of the title compounds are reported and assigned. Theit crystal structures were determined by X-ray diffraction. Crystal data: (CH₃CN₂S₂)₅[CoCl₄]Cl₃, orthorhombic, P2₁2₁2₁, Z = 4, a = 830, b = 1603, c = 2443 pm at 180 K (structure determination with 1787 observed independent reflexions, R = 0.070); (CH₃CN₂S₂)Cl, triclinic, P2₁2₁2₁, Z = 4, a = 749, b = 819, c = 1015 pm, α = 84.9, β = 67.4, γ = 84.6° at 296 K (2653 reflexions, R = 0.040). Both compounds are ionic, having chloride and distorted tetrahedral CoCl₄^2? anions and planar 4-methyl-1,2,3,5-dithiadiazolium cations which nearly fulfill C_2v symmetry. The (CH₃CN₂S₂)₅[CoCl₄]Cl₃ structure contains five symmetry independent cations, (CH₃CN₂Cl has two symmetry independent cations, all being nearly equal. No nitrogen atom but all sulfur atoms of the cations have contact with three to five chlorine atoms, and as a rule there is one chloride ion which is coplanar with the cation and exhibits rather short distances to both S atoms (288 to 309 pm); therefore, the positive charge of the cations must be concentrated on the sulfur atoms.     

Addukte des Oxo-tetrachloro-niobat(V)-Ions Bildung,Schwingungsspektren und Kristallstrukturen von PPh4[NbOCl4(OH2)] und (PPh4)2[NbOCl4(O2PCl2)] · 2 CH2Cl2

Adducts of Oxotetrachloro-niobate (V). Formation, Vibrational Spectra, and Crystal Structures of PPh₄[NbOCl₄(OH₂)] and (PPh₄)₂[NbOCl₄(O₂PCl₂)] · 2 CH₂Cl₂ Crystalline (PPh₄)₂[NbOCl₄(O₂PCl₂)] · 2 CH₂Cl₂ was obtained by hydrolysis of PPh₄[NbSCl₄] in the presence of POCl₃ in CH₂Cl₂. Experiments to obtain the same compound from PPh₄Cl, POCl₃, NbCl₅, and H₂O yielded PPh₄[NbOCl₄(OH₂)]. I.R. spectra of both compounds are discussed. The crystal structure determinations with X-ray diffraction data in both cases show quadratic-pyramidal NbOCl₄^? ions to which a molecule of either H₂O or a PO₂Cl₂^? ion is attached in trans-position to the O atom. PPh₄[NbOCl₄(OH₂)]: tetragonal, space group P4/n, a = 1 308, c = 734 pm, Z = 2, packing as in the AsPh₄[RuNCl₄] type; refinement down to R = 0.046 for 681 reflexions. (PPh₄)₂[NbOCl₄(O₂PCl₂)] · 2 CH₂Cl₂: triclinic, space group P1 , a = 1172, b = 1187, c = 2105 pm, α = 88.40, β = 83.20, γ = 71.28°, Z = 2, packing similar as in (AsPh₄)₂[NbOCl₅] · 2 CH₂Cl₂; refinement to R = 0.059 for 2 502 reflexions.     

Chlorthionitrenkomplexe des Rheniums Die Kristallstruktur von AsPh4[ReCl4(NSCl)2] · CH2Cl2

Chlorothionitrene Complexes of Rhenium. Crystal Structure of AsPh₄[ReCl₄(NSCl)₂] · CH₂Cl₂ Rhenium pentachloride reacts in POCl₃ solution with (NSCl)₃ forming the chlorothionitrene complexes [(Cl₃PO)ReCl₄(NSCl)] ( I ) and [(Cl₃PO)ReCl₃(NSCl)₂] ( II ). I reacts with AsPh₄Cl in CH₂Cl₂ solution under abstraction of SCl₂ and POCl₃, yielding AsPh₄[ReNCl₄], while II forms the complex AsPh₄[ReCl₄(NSCl)₂] · CH₂Cl₂. The i.r. spectra of the compounds are discussed and assigned. The crystal structure of AsPh₄[ReCl₄(NSCl)₂] · CH₂Cl₂ was determined and refined with X-ray diffraction data (R = 0.031 for 2785 reflexions). It crystallizes in the space group Pī with two formula units per unit cell; the lattice constants are a = 1119, b = 1144, c = 1473 pm, α = 77.6, β = 70.8 and γ = 71.2°. The two NSCl ligands have cis arrangement with nearly linear Re?N?S groups, with interatomic distances corresponding to double bonds. The Re? Cl bonds are somewhat longer than usual and show no trans-effect; this is possibly due to Cl…?H? C bridges.     

Die Kristallstrukturen von [Ph3PMe]Cl·CH2Cl2, [Ph4P]NO3·CH2Cl2 und [Ph4P]2[SiF6]·CH2Cl2

Crystal Structures of [Ph₃PMe]Cl·CH₂Cl₂, [Ph₄P]NO₃·CH₂Cl₂, and [Ph₄P]₂[SiF₆]·CH₂Cl₂ The crystal structures of the title compounds are determined by X‐ray diffraction. In all cases, the included dichloromethane molecules as well as the phosphonium cations are involved to form hydrogen bridges with the anions. [Ph₃PMe]Cl·CH₂Cl₂ ( 1 ): Space group , Z = 2, lattice dimensions at 100 K: a = 890.3(1), b = 988.0(1), c = 1162.5(1) pm, α = 106.57(1)°, β = 91.79(1)°, γ = 92.60(1)°, R₁ = 0.0253. [Ph₄P]NO₃·CH₂Cl₂ ( 2 ): Space group P2₁/n, Z = 4, lattice dimensions at 193 K: a = 1057.0(1), b = 1666.0(1), c = 1358.9(1) pm, β = 100.10(1)°, R₁ = 0.0359. [Ph₄P]₂[SiF₆]·CH₂Cl₂ ( 3 ): Space group , Z = 2, lattice dimensions at 193 K: a = 1063.9(1), b = 1233.1(1), c = 1782.5(2) pm, α = 76.88(1)°, β = 83.46(1)°, γ = 72.29(1)°, R₁ = 0.0332.     

Trichloro-bridged diruthenium (III,III) complexes: X-ray isomorphous structures of [Ph3X=O···H···O=XPh3][Ru2Cl7(XPh3)2]·0.5(CH2Cl2)(H2O)(X = As or P)

The triply chloro-bridged binuclear complexes [Ph₃X=O···H···O=XPh₃][Ru₂Cl₇(XPh₃)₂]·0.5(CH₂Cl₂)(H₂O) (X = As or P) were obtained from [RuCl₃(XPh₃)₂DMA]·DMA (DMA = dimethylacetamide) CH₂Cl₂/Et₂O solution. The structures were characterized by X-ray diffraction studies. The complexes are formed from two Ru atoms bridged by three chloride anions. The two ruthenium atoms are also coordinated to two non-bridging Cl atoms and an AsPh₃ or PPh₃ ligand respectively. As an interesting feature, the cations of these complexes are protons, trapped in a very short hydrogen bond between two triphenylarsine or triphenylphosphine oxide molecules.     

Beitrag zur Chemie der Phosphor-Stickstoff-Verbindungen. Reaktion von Cl2(O)P?NH?P(O)Cl2 mit Tetrahydrofuran

Contribution to the Chemistry of Phosphorus-Nitrogen Compounds. Reaction of Cl₂(O)P? NH? P(O)Cl₂ with Tetrahydrofuran As well as many phosphorus compounds, the imidodiphosphoryl tetrachloride HN(P(O)Cl₂)₂ reacts with a large excess of tetrahydrofuran to give the polytetrahydrofuran. Otherwise, if we use smaller molecular ratios THF/HN(P(O)Cl₂)₂ (1/2 to 3) a polytetrahydrofuran with short chains and N(ω-hydroxypolytetramethylenoxy)imidodiphosphoryl tetrachloride R? N(P(O)Cl₂)₂; R = H(O(CH₂)₄)_n- are obtained at 22° or 30°C. The ¹H and ³¹P n.m.r. spectra show that oxonium ions are formed with progressive additions of THF to HN(POCl₂)₂/CCl₄ solution. Then two mechanisms have been considered by nucleophilic attack on carbon α of oxonium ion coming from: the free electronic dublett on oxygen of THF to give polytetrahydrofuran or (and) from the nitrogen of imido diphosphoryl tetra chloride anion ((Cl₂OP)₂N)^? to obtain N(ω-hydroxypolytetramethylenoxy)imidodiphosphoryl tetrachloride.     

Darstellung und Kristallstruktur von (CH3NH3)8[NdCl6][NdCl4(H2O)2]2Cl3

Preparation and Crystal Structure of (CH₃NH₃)₈[NdCl₆][NdCl₄(H₂0)₂]₂Cl₃ (CH₃NH₃)₈[NdCl₆][NdCl₄ (H₂O)₂]₂Cl₃ is for the first time prepared and investigated by X-ray, single crystal work. It crystallizes in the monoclinic system (space group C2/m, Z = 2) with a = 9.358(5), b = 17.424(9), c = 15.360(8) Å, β = 108.30(4)°. The structure contains besides isolated Cl^? ions distorted [NdCl₆]^3? octahedra and [NdCl₄(H₂O)₂]^? chains.     

Syntheses and Structures of S4N4(OCH3)2 and CH3OS4N4(O)Cl

The reaction of S₄N₄Cl₂ with CH₃OH gives S₄N₄(OCH₃)₂, a simple dimethoxoderivative of S₄N₄. Its overall geometry is analogous to other compounds of the S₄N₄X₂ type. The chlorination of S₄N₄(OCH₃)₂ leads to the oxidation of one sulfur atom to S^VI and CH₃OS₄N₄(O)Cl is formed. The compounds were characterized by ir spectroscopy and their crystal structures were determined from single crystal diffraction data collected at ?153°C. The presence of S^VI in the molecule of CH₃OS₄N₄(O)Cl is manifested by a marked shortening of the bonds formed by this atom as compared with S₄N₄Cl₂ and S₄N₄(OCH₃)₂.     

Kationische und anionische kantenverknüpfte Dimere in [Dy2(Dibenzo-18-Krone-6)2Cl4][Dy2(CH3CN)2Cl8]. Synthese und Kristallstruktur

Cationic and Anionic Edge-Connected Dimers in [Dy₂(dibenzo-18-crown-6)₂Cl₄][Dy₂(CH₃CN)₂Cl₈]. Synthesis and Crystal Structure Colourless single crystals of 2 DyCl₃ · dibenzo-18-crown-6 · CH₃CN are obtained upon reaction of DyCl₃ or KDy₂Cl₇ with dibenzo-18-crown-6-ether in acetonitrile. The crystal structure (triclinic, P1 , Z = 2; a = 1 105.6(2); b = 1 144.5(3); c = 1 367.8(3); α = 93.46(1); β = 92.27(1); γ = 117.45(1); R = 0.046; R_w = 0.033) contains cationic and anionic edge-connected dimers according to [Dy₂(dibenzo-18-crown-6)₂Cl₄]²⁺ [Dy₂(CH₃CN)₂Cl₈]²⁺ where Dy1 and Dy2 are coordinated by 3 and 5 chloride ions, respectively.