THE CRYSTAL,MOLECULAR STRUCTURE AND LIGAND BONDING IN TETRAKIS (N,N′-DIMETHYLTHIOUREA) NICKEL (II) BROMIDE DIHYDRATE

Abstract

The crystal structure of tetrakis(N,N′-dimethylthiourea)nickel(II) bromide dihydrate has been determined by three-dimensional x-ray diffraction from 1916 counter-data reflections collected at room temperature.

The structure consists of Ni[SC(NH)₂(CH₃)₂]²⁺ ₄ molecular ions, Br^? ions and waters of hydration. The nickel is located on a center of symmetry and is coordinated to four sulfur atoms in a square planar configuration. The waters of hydration and the bromide ions are involved in hydrogen bonding to the N,N′-dimethylthiourea (dmtu) groups. The orientation of the dmtu groups is such that two bond through the sulfur sp² orbital and the others bond through the π-orbitals of the dmtu group. The Ni-S distances are 2.204 ± 0.002 Å and 2.230 ± 0.002 Å, and the Ni-S-C angles are 106.2 ± 0.2Å and 110.3 ± 0.3°. The dmtu groups are planar except for methyl hydrogens.

The crystals are monoclinic, P2₁/a with a = 13.424 ± 0.002 Å, b = 12.321 ± 0.005 Å, c = 8.460 ± 0.008 Å β = 107.07 ± 0.05°, ρ₀ = 1.67 g cm^?3, ρ_c = 1.66 g cm^?3 and Z = 2. The structure was refined by full-matrix least-squares to a conventional R of 0.0466.     

Synthesis,Structure and Thermodynamic Property of a New Lithium Borate: Li4[B8O13(OH)2]·3H2O

A new hydrated lithium borate, Li₄[B₈O₁₃(OH)₂]·3H₂O, has been hydrothermally synthesized and characterized by single crystal X‐ray diffraction, FT‐IR spectroscopy, simultaneous TGA‐DTA and chemical analysis. It crystallizes in the triclinic, space group , a=8.4578(5) Å, b=8.7877(5) Å, c=10.8058(7) Å, α=87.740(3)°, β=71.819(3)°, γ=61.569(3)°, Z=2, V=665.26(7) ų, D_c=2.043 g/cm³. Its crystal structure features polyborate anionic layers with the larger odd 13‐membered boron rings constructed by [B₈O₁₃(OH)₂]^4? FBBs. Through designing the thermochemical cycle, the standard molar enthalpy of formation of this borate was determined to be ?(7953.8±6.6) kJ·mol^?1 by using a heat conduction microcalorimeter.     

The Periodate‐Based Double Perovskites M2NaIO6 (M = Ca,Sr, and Ba)

The crystal structures of the M₂NaIO₆ series (M = Ca, Sr, Ba), prepared at 650 °C by ceramic methods, were determined from conventional laboratory X‐ray powder diffraction data. Synthesis and crystal growth were made by oxidizing I^– with O₂^(air) to I⁷⁺ followed by crystal growth in the presence of NaF as mineralizator, or by the reaction of the alkali‐metal periodate with the alkaline‐earth metal hydroxide. All three compounds are insoluble and stable in water. The barium compound crystallizes in the cubic space group Fm3m (no. 225) with lattice parameters of a = 8.3384(1) Å, whereas the strontium and calcium compounds crystallize in the monoclinic space group P2₁/c (no. 14) with a = 5.7600(1) Å, b = 5.7759(1) Å, c = 9.9742(1) Å, β = 125.362(1)° and a = 5.5376(1) Å, b = 5.7911(1) Å, c = 9.6055(1) Å, β = 124.300(1)°, respectively. The crystal structure consists of either symmetric (for Ba) or distorted (for Sr and Ca) perovskite superstructures. Ba₂NaIO₆ contains the first perfectly octahedral [IO₆]^5– unit reported. The compounds of the ortho‐periodates are stable up to 800 °C. Spectroscopic measurements as well as DFT calculations show a reasonable agreement between calculated and observed IR‐ and Raman‐active vibrations.     

Die Struktur der Hydrate von Co3[Co(CN)6]2 und Cd3[Co(CN)6]2

The crystal structures of Co₃[Co(CN)₆]₂, 12 H₂O (a, = 10.210 ± 0.005 Å) and Cd₃[Co(CN)₆]₂, 12 H₂O (a = 10.590 ± 0.005 Å) have been determined by X-ray powder methods. According to the measured density the unit cell contains 1 1/3 formula units with 4 Co²⁺ (Cd²⁺) in 4a, 2 2/3 Co³⁺ in 4b, 16 C and 16 N in 24e, 8 H₂O_I near 24e, (96k) and 8 H₂O_II near 8 _c (192 l). Structure factor calculations based on the space group O_h⁵ - F m 3 m lead to the following final values of the reliability index R: 0.038 (Co₃[Co(CN)₆]₂, 12 H₂O) and 0.037 (Cd₃[Co(CN)₆]₂, 12 H₂O). The interatomic distances for the cobaltous compound (in parentheses for the cadmium compound) are: Co³⁺-C: 1.88 Å (1.89); C-N: 1.15 Å (1.17); Co²⁺-N: 2.08 Å (2.24); Co²⁺-O_I: 2.10 Å (2.27); shortest O_I-H-O_II-bonds: 2.89 Å (2.82). Co³⁺ is octahedrally coordinated by six carbon atoms, the divalent metal ion by four nitrogen atoms and two water molecules. The two different metal ions are connected by M²⁺-N-C-Co³-bonds to a threedimensional network. The infrared and electronic spectra are shown to be in agreement with the results of the structure analyses of these compounds. The observed positions of the OH-stretching vibrations lead to a hydrogenbond-length of 2.8–2.95 Å.     

Investigation of the Quasi Binary System BaAu–BaPt

Phase equilibria in the system BaAu–BaPt have been investigated by X‐ray powder diffraction. Depending on composition, three structure types occur, the FeB type for BaAu, and NiAs for BaPt, while the CrB type of structure is adopted in between. The homogeneity range for the CrB type of structure was established to extend from BaPt_0.15Au_0.85 to BaPt_0.90Au_0.10. The respective lattice parameters vary linearly, in accordance with Vegard's law. The crystal structure of the new CrB type compounds have been confirmed by X‐ray powder diffraction for the solid solution range, and by single crystal X‐ray diffraction exemplary for the composition BaAu_0.5Pt_0.5 (Cmcm; a = 4.3915(5) Å; b = 11.9149(12) Å; c = 4.7920(5) Å; Z = 4). BaAu was also established by single crystal structure determination (Pnma; a = 8.3220(10) Å; b = 4.9252(10) Å; c = 6.3844(10) Å; Z = 4) to complete the results. According to ESCA measurements BaAu_0.5Pt_0.5 and BaAu can be formulated as [Ba²⁺·0.5e^?]·[Au^?_0.5·Pt^2?_0.5] and [Ba²⁺·e^?]·[Au^?], respectively.     

Emission studies of the mechanism of gaseous biacetyl photolysis at 3450, 3650, 3880, and 4358 a and 28°C

The quantum yields of phosphorescence (Φ_p) of biacetyl have been determined in pure biacetyl, biacetyl-SO₂, and biacetyl-c-C₆H₁₂ mixtures in experiments using bands of radiation centered at 3450, 3650, 3880, and 4348 Å. It has been shown that the unexpected effect of gas concentration on the quantum yields of the sulfur dioxide triplet-sensitized phosphorescence of biacetyl resulted largely from the significant destruction of biacetyl triplets at the wall of the cell. The kinetics of the variation of Φ_p with [Ac₂], wavelength of the absorbed light, and added gases provide new estimates of the energy relations and the rate constants for the decomposition reaction of vibrationally rich biacetyl molecules in the first excited singlet state (¹Ac₂?): ¹Ac₂? → products (1), ¹Ac₂? + Ac₂ → ¹Ac₂ + Ac₂ (2); the minimum energy necessary in ¹Ac₂? for reaction (1) to occur is estimated to be about 72.8 kcal/mole above the ground state of biacetyl: k₁/k₂ = (4.3 ± 0.1) × 10^?3M at 3450 Å, (4.07 ± 0.04) × 10^?4M at 3650 Å, and (5.6 ± 0.4) × 10^?5M at about 3800 Å. The variation of the rate constant ratio is shown to be consistent with the expectations of the simple theory of excited molecule decomposition. Biacetyl triplet (³Ac₂) rate constants were determined by measurements of Φ_p in O₂ and NO-containing mixtures: ³Ac₂ + S → (Ac₂–S, products) (8); for O₂ = S, k₈ = (5.76 ± 0.40) × 10⁸ (3650 Å experiments), (5.76 ± 0.27) × 10⁸ (4358 Å); for NO = S, k₈ = (3.34 ± 0.20) × 10⁹ (3650 Å), (3.33 ± 0.18) × 10⁹ 1./mole-sec (4358 Å). A comparison between these and previous findings of the SO₂ triplet (³SO₂)-sensitized excitation of biacetyl [5,6] show that the decomposition of the initial ³Ac₂ product of the exothermic energy transfer reaction ³SO₂ + Ac₂ → SO₂ + ³Ac₂ is unimportant.     

Synthesis and Structure of ThTe2I2

The new ternary compound ThTe₂I₂, which crystallizes in the NbS₂Cl₂ structure type, was prepared from the elements and characterized by single‐crystal X‐ray diffraction. It adopts a monoclinic layer structure where binuclear [Th₂(Te₂)₂]⁴⁺ units with square‐antiprismatically coordinated thorium are linked together by I^– anions to form sheets parallel to the (001) plane. The space group is C2/m and the lattice constants are a = 7.642(1) Å, b = 14.336(4) Å, c = 7.727(2) Å, and β = 111.27(2)° for Z = 4. The final R1/wR2 for the crystal structure refinement was 0.029/0.073.     

Lithium Ion Motion in Lithium Nitridoborate Chalcogenides Li5(BN2)Ch (Ch = Se,Te)

The compounds Li₅(BN₂)Se and Li₅(BN₂)Te were synthesized at 900 °C in a closed system utilizing weld shut niobium ampoules and obtained as white microcrystalline powders. Their crystal structures were solved and refined on the basis of single‐crystal X‐ray diffraction data with the space group I4₁md [a = 6.3983(4) Å, c = 11.1072(9) Å for Li₅(BN₂)Se and a = 6.5878(3) Å, c = 11.4382(7) Å for Li₅(BN₂)Te]. The temperature dependent Li⁺ motion was investigated by ⁷Li MAS NMR spectroscopy.     

Syntheses,structural determination,and binding studies of nine-coordinate mononuclear (mnH)2[DyIII(Httha)]·3H2O and (enH2)3[DyIII(ttha)]2·9H2O

Two dysprosium coordination compounds, (mnH)₂[Dy^III(Httha)]·3H₂O (1) (H₆ttha?=?triethylenetetramine-N,N,N′,N″,N′′′,N′′′-hexaacetic acid and mn?=?methylamine) and (enH₂)₃[Dy^III(ttha)]₂·9H₂O (2) (en?=?ethylenediamine), were synthesized through direct heating and characterized by elemental analysis, FT-IR, thermal analysis, and single-crystal X-ray diffraction. X-ray diffraction analysis displays that 1 is a mononuclear nine-coordinate complex with a pseudo-monocapped square antiprismatic conformation (MCSAP) crystallizing in the monoclinic crystal system with P2(1)/c space group. The crystal data are as follows: a?=?16.1363(19)?Å, b?=?13.9336(11)?Å, c?=?13.6619(14)?Å, β?=?102.2490(10)°, and V?=?3001.8(5)?ų. There are two kinds of methylamine cation in 1. They connect [Dy^III(Httha)]^2?and crystal waters through hydrogen bonds, leading to formation of a 2-D ladder-like layer structure. The polymeric 2 also is a nine-coordinate structure with a pseudo-MCSAP crystallizing in the monoclinic crystal system with P2/c space group. The cell dimensions are: a?=?17.7801(16)?Å, b?=?9.7035(10)?Å, c?=?22.096(2)?Å, β?=?118.874(2)°, and V?=?3338.3(6)?ų. In 2 there are also two types of ethylenediamine cations. One connects three adjacent [Dy^III(ttha)]^3? complex anions through hydrogen bonds and the other is symmetrical forming hydrogen bonds with two neighboring [Dy^III(ttha)]^3? complex anions. These hydrogen bonds result in formation of a 2-D ladder-like layer structure as well.     

Synthesis,crystal and molecular structure of [Na(B15C5)+]2[Hg3Cl8]2-·H2O

A crystal complex with the formula [Na(B15C5)⁺]₂ [Hg₃Cl₈]^2-·H₂O was synthesized by the reaction of benzo-15-crown-5 with sodium chloride and mercuric chloride. Its crystal and molecular structures were determined by X-ray diffraction. Crystal data: monoclinic, space group P2/n with cell dimensions of a= 17.809(4) Å, b= 13.938(4) Å, c= 17.984(4) Å, β=107.14°, Z=4, V= 4266.2 Ų. R and R_w are 0.043 and 0.053, respectively. The results obtained by spectral analysis are consistent with those of the structural analysis.     

SYNTHESIS AND CHARACTERIZATION OF MANGANESE(III) HYDROXYL-CONTAINING SCHIFF-BASE COMPLEXES: [Mn(III)(Hvanpa)2(NCS)] AND [Mn(III)(Hvanpa)2]Cl · H2O (H2vanpa ˭ 1-(3-METHOXYSALICYLALDENEAMINO)-3-HYDROXYPROPANE)

Abstract

The manganese complexes, [Mn(III)(Hvanpa)₂(NCS)] (1) and [Mn(III)(Hvanpa)₂]Cl · H₂O (2), have been prepared and the crystal structure of complex 2 determined using X-ray crystallography. The monomeric complex has a six-coordinate octahedral geometry. The complex crystallizes in the triclinic space group P-1 with a = 11.446(5) Å, b = 12.782(6) Å, c = 9.023(3) Å, α = 93.92(3)°, β = 97.05(3)°, γ = 65.42(2)°, V = 1169.0(9) ų and Z = 2. The Mn-O and Mn-N distances in the equatorial plane are in agreement with those found for other manganese (III) Schiff-base complexes. In the axial direction, the Mn-O distances of 2.256(3) and 2.236(3) Å, respectively, are about 0.4 Å longer than those in the equatorial plane due to Jahn-Teller distortion at the d ⁴ manganese(III) center. In the crystal, each chloride ion is linked through hydrogen bonding with two hydrogen atoms from the coordinated hydroxyl groups at the apical site. The lattice water molecules also interact with the phenolic oxygen atoms through hydrogen bonding.     

Crystal and Molecular Structure of (±)-8,8-Dimethyl-6,7-diazabicyclo[3.3.0]octa-1,6-diene 7-oxide

The exclusive product of thermal rearrangement of (±)-7-isopropylidene-2,3-diazabicyclo[2.2.1]hept-2-ene N-oxide (2) has been identified as the title compound (1). The compound crystallizes in the orthorhombic space group Pbca (No. 61), with a= 8.953 (2), b= 12.740 (2), c=14.446 (3) Å; Z= 8; p_x=1.227 g cm^?3. The details of the molecular structure are not unusual, except for a long C–N distance (C(8)–N(7), 1.560 (4) Å). No significant short intermolecular contacts are observed in the crystal.     

The photolysis of N2O at 2139 Å and 1849 Å

The method of chemical difference was utilized to accurately determine the relative importance of all the reaction steps in the direct photolysis of N₂O at 2139 Å (25° and 250°C) and 1849 Å (25° C), as well as in the Hg6(¹P₁)-sensitized photolysis of N₂O at 1849 Å (25°C). In all cases, the primary process is predominantly, if not exclusively, Experiments with trace amounts of C₃H₆ added showed a slight, but not significant, difference in product ratios (N₂ and O₂). From these experiments the quantum yield of O(³P) from all possible sources was estimated as 0.02 ± 0.02. Experiments with excess N₂ at 1849 Å indicated that O(¹S) was not produced in the direct photolysis. The O(¹S) yield is probably zero, and certainly <0.05. The O(¹D) atom can react with N₂O via The ratio k₂/k₃ was found to be 0.69 ± 0.05 in all cases. When combined with other data from our laboratory, the average value is 0.65 ± 0.07. This represents the value for translationally energetic O(¹D) atoms. When excess He was added to remove the excess translational energy, k₂/k₃ rose to 0.83 ± 0.06, which is in reasonable agreement with the value of 1.01 ± 0.06 found in another laboratory. We conclude that for O(¹D) atoms with no excess thermal energy, k₂/k₃ = 0.90 ± 0.10.     

Synthesis and Crystal Structures of the First Quaternary Tantalum Thiogermanates,ATaGeS5 (A = K,Rb, Cs)

The new quaternary thiogermanates, ATaGeS₅ (A = K, Rb, Cs) were prepared with the use of halide fluxes and the crystal structures of the compounds were determined by single‐crystal X‐ray diffraction methods. The compounds are isostructural and crystallize in space group P\bar{1} of the triclinic system with two formula units in a cell of dimensions: a = 6.937(1) Å, b = 6.950(2) Å, c = 8.844(3) Å, α = 71.07(2)°, β = 78.56(2)°, γ = 75.75(2)°, V = 387.6(2) Å³ for KTaGeS₅; a = 6.996(3) Å, b = 7.033(3) Å, c = 8.985(4) Å, α = 70.33(3)°, β = 78.12(4)°, γ = 75.63(4)°, V = 399.6(3) Å³ for RbTaGeS₅; a = 7.012(4) Å, b = 7.202(3) Å, c = 9.267(5) Å, α = 68.55(3)°, β = 77.27(4)°, γ = 74.75(4)°, V = 416.2(4) Å³ for CsTaGeS₅. The structures of ATaGeS₅ (A = K, Rb, Cs) are comprised of anionic infinite two‐dimensional {}_\infty^2 [TaGeS₅^–] layers separated from one another by alkali metal cations (A⁺). Each layer is made up of tantalum centered sulfur octahedra and pairs of edge‐sharing germanium centered sulfur tetrahedra. The classical charge valence of these compounds should be represented by [A⁺][(Ta⁵⁺)(Ge⁴⁺)(S^2–)₅]. UV/Vis diffuse reflectance measurements indicate that they are semiconductors with optical bandgaps of ca. 2.0 eV.     

A new type of liquid crystal involving hydrogen bonding: single crystal X-ray structure characterization and properties of the liquid crystal

A new liquid crystal involving hydrogen bonding between 4-hexyloxybenzoic acid and 4-octyloxylphenylethynylpyridine has been investigated by DSC, polarizing optical microscopy and X-ray diffraction. The mesogen shows a nematic phase and an unknown liquid crystalline phase. The liquid crystal crystallizes with a triclinic space group P-1 with the parameters: a = 8.879(2)Å, b = 10.137(2)Å, c = 17.629(4)Å; α = 104.16(3)°, β = 95.47(3)°, γ = 101.48(3)°; V = 1490.3(6)ų; Z = 2; F(000) = 572; μ = 0.076 mm^?1; λ(MoK_α) = 0.71073 Å; final R ₁ = 0.0435. The complex is formed by strong intermolecular hydrogen bonding.     

Crystal Structure and Thermal Behaviour of K2[CrF5·H2O]

K₂[CrF₅·H₂O] is monoclinic: a = 9.6835(3) Å, b = 7.7359(2) Å, c = 7.9564(3) Å, β = 95.94(1)°, Z = 4, space group C2/c (n^o 15). Its crystal structure was solved from its X‐ray powder pattern recorded on a powder diffractometer, using for the refinement the Rietveld method. It is built up from isolated octahedral [CrF₅·OH₂]^2? anions separated by potassium cations. The dehydration of K₂[CrF₅·H₂O] leads to anhydrous orthorhombic K₂CrF₅: a = 7.334(2) Å, b = 12.804(4) Å, c = 20.151(5) Å, Z = 16, space group Pbcn (n^o 60), isostructural with K₂FeF₅.     

Effects of Bis(aromatic) Pendants on Recognition of Nucleobase Thymine by Zn2+ -1,4,7,10-tetraazacyclododecane (Zn2+ -cyclen)

We have previously shown that the nucleobase thymine binding to Zn²⁺ -cyclen (cyclen=1,4,7,10-tetraazacyclododecane) complex became stronger by appending acridine, naphthalene, or quinoline rings to the cyclen. Amongst these, the pendant bis((1-naphthyl)methyl) or bis((4-quinolyl)methyl) groups yielded the most effective thymine-recognizing Zn²⁺ -cyclen complexes [J. Am. Chem. Soc., 121 (1999) 5426]. The present study was undertaken to find causes of the bis(aromatic) ring effect by X-ray crystal structure analysis and NMR studies. The crystal structure of the Zn²⁺ -bis((1-naphthyl)methyl)-cyclen complex with a deprotonated 1-methylthymine (1-MeT) failed to show the anticipated evidence for the double ~ - ~ stacking interactions between the two naphthalenes and the Zn 2+ -bound 1-MeT m (1-MeT m =N(3')-deprotonated 1-MeT). Crystal data: formula C₃₆ H₄₇ N₇ O₇ Zn, M r =755.19, monoclinic, space group P2₁/ c (No. 14), a =15.438(2) Å, b =14.093(3) Å, c =16.726(2) Å, g =90.53(1) V =3638.7(8) Å 3 Z =4, R =0.035, R _w =0.049. However, the ¹H NMR studies of Zn²⁼ -bis((4-quinolyl)methyl)-cyclen with 1-MeT in varying H₂O/CH₃ CN solution showed increasing upfield shifts of Me(5') and H(6') of the Zn²⁺ -bound 1-MeT in more aqueous media, indicating that the double intercalation with the two quinolines became more significant in more protic environments. We conclude that the double ~ - ~ stacking effect accounts for the enhanced recognition of thymine base by the appended bis((1-naphthyl)methyl) or bis((4-quinolinyl)methyl) groups.     

Preparation and Crystal Structure of the Strontium Aluminium Fluoride Sr5Al2F16

Single crystals of Sr₅Al₂F₁₆ crystallize in colourless translucent plates and have been prepared by solid state synthesis, starting from stoichiometric mixtures of the binary fluorides. The crystal structure has been determined and refined from single crystal diffractometer data (orthorhombic, space group Ccca (no. 68), a = 7.4488(4) Å, b = 12.4714(7) Å, c = 14.1411(8) Å, V = 1313.67(13) ų, Z = 4, R[F ² > 2σ(F ²)] = 0.025; wR2(F ² all) = 0.056, 971 structure factors, 56 parameters) and can be derived from a slightly distorted c.c.p. arrangement where 7/8 of the c.c.p. positions are occupied by the metal atoms. The main features of the structure are AlF₆ octahedra and SrF₈ polyhedra with mean distances d(Al–F) = 1.791 Å and d(Sr–F) = 2.531 Å, respectively.     

Two Hybrid Compounds Constructed from Vanadate Clusters and Secondary Metal‐Bis(imidazole) Subunits

Two new inorganic–organic vanadate hybrid compounds [Mn(Hbbi)₂(V₄O₁₂)] ( 1 ) and [Cd(Hbbi)₂(V₄O₁₂)] ( 2 ) (bbi = 1,1’‐(1,4‐butanediyl)bis(imidazole)) were hydrothermally synthesized and characterized by elemental analyses, IR spectroscopy, TG and single‐crystal X‐ray diffraction. The two compounds crystallize in monoclinic system, P2₁/c space group with a = 8.556(5) Å, b = 10.761(5) Å, c = 16.917(5) Å, β = 93.032(5) ^o, V = 1555.4(12) Å³, Z = 2, R = 0.0390 for 1 and a = 8.657(5) Å, b = 10.743 (5) Å, c = 16.864 (5) Å, β = 93.81(5)^o, V = 1564.9 (12) Å³, Z = 2, R = 0.0717 for 2 . Single‐crystal X‐ray diffraction analysis reveals that the two compounds are isostructural and both consist of one‐dimensional (1D) chains, which are constructed from vanadate anion clusters and [M(Hbbi)₂]⁴⁺ cation groups [M = Mn^II ( 1 ), Cd^II ( 2 )]. Moreover, the polymeric chains are ultimately packed into a three‐dimensional (3D) supramolecular framework through C–H ··· O and N–H ··· O hydrogen bonding interactions.     

Comparison of Crystal Structures of New Racemic Chiral Compounds Showing and Not Showing the Phenomenon of Preferential Enrichment

Abstract

The crystal structures of (±)-[2-[4-(3-ethoxy-2-hydroxypropoxy)phenylcarbamoyl]ethyl] trimethylammonium p-chlorobenzenesulfonate [(±)-NCMe₃] and its terminal methoxy derivative, (±)-NCMe₃-OMe, are compared. The former racemate exhibited the phenomenon of Preferential Enrichment, whereas the latter failed to do so. Crystal data, (±)-NCMe₃: CuKα radiation, space group P 1, Z = 2, a = 9.848(5), b = 14.823(3), c = 9.147(1) Å, α = 97.81(1), β = 92.68(3), γ = 105.92(2)°, D _calc = 1.355 g/cm³, R = 0.056 for 3213 observed reflections; (±)-NCMe₃-OMe: CuKα radiation, space group P 1, Z = 2, a = 11.350(1), b = 14.568(2), c = 8.2981(4) Å, α = 94.346(7), β = 112.376(5), γ = 78.622(9)°, D _calc = 1.343 g/cm³, R = 0.069 for 1519 observed reflections.