Crystal structures of mixed compounds Cu(2)Gly(D-Ser)(L-Ser)2 and Cu(2)Gly 3(L-Ser)

-The crystal structures of mixed coordination compounds, Cu(2)Gly(D-Ser)(L-Ser)₂(I) and Cu(2)Gly ₃(L-Ser)(II), which contain the amino acid residues of glycine (Gly) and serine (Ser) in the 1: 3 and 3: 1 ratio, respectively, are studied by electron diffraction. Crystals I and II are triclinic, Z = 1, and space group P1. For I, a = 8.96(2) Å, b = 9.66(2) Å, c = 5.07(2) Å, α = β = 90°, and γ = 92.8(3)°. For II, a = 8.37(2) Å, b = 9.65(2) Å, c = 5.06(2) Å, α = β = 90°, and γ = 92.8(3)°. Compounds I and II have layered structures that are based on the CuGly(L-Ser) fragment. Structures I and II differ mainly in their interlayer spacing and configuration of the interlayer space.     

Thermolysis of the tetrahedrane cluster PhCCo3(CO)3(μ-CO)Cp2 with the unsaturated diphosphine ligands (Z)-Ph2PCH=CHPPh2 and 4,5-Bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd): Redox properties and molecular structure of PhCCo3(CO)(μ-CO)[(Z)-Ph2PCH=CHPPh2]Cp2

Thermolysis of the tricobalt cluster PhCCo₃(CO)₃(μ-CO)Cp₂ (1) with the diphosphine ligands (Z)-Ph₂PCH=CHPPh₂ and 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) has been examined and found to give the diphosphine-substituted clusters PhCCo₃(CO)[(Z)-Ph₂PCH=CHPPh₂](μ-CO)Cp₂ (2) and PhCCo₃(CO)(bpcd)(μ-CO)Cp₂ (3) in moderate yield. The new compounds 2 and 3 have been isolated and characterized in solution by IR and NMR (¹H and ³¹P) spectroscopies. VT ³¹P NMR data reveal that the chelating diphosphine ligand is fluxional in solution and exhibits a rocking motion between the axial and equatorial sites that renders both phosphorus moieties identical at ambient temperature. The molecular structure of PhCCo₃(CO)[(Z)-Ph₂PCH=CHPPh₂](μ-CO)Cp₂ (2) has been determined by X-ray crystallography. PhCCo₃(CO)[(Z)-Ph₂PCH=CHPPh₂](μ-CO)Cp₂ crystallizes, as the CH₂Cl₂ solvate, in the monoclinic space P2₁/n, a = 16.822(2) Å, b = 10.554(1) Å, c = 23.135(3) Å, β = 100.944(2)^°, V = 4032.4(8) ų, Z = 4, and d _calc = 1.537 Mg/m³; R = 0.0488, R _w = 0.0725 for 9431 reflections with I > 2σ(I). The solid-state structure of cluster 2 establishes the chelating nature of the ancillary (Z)-Ph₂PCH=CHPPh₂ ligand at the unique Co(CO)P₂ center via coordination at an equatorial and an axial site. The redox behavior of clusters 2 and 3 has been explored by cyclic voltammetry and chronocoulometry. Each cluster reveals the presence of two one-electron oxidations of common origin due to the oxidation of a Co–Co bonding orbital. Whereas cluster 2 does not exhibit an accessible reduction process in CH₂Cl₂, a ligand-based one-electron reduction was found for cluster 3 given its low-lying π* LUMO associated with the bpcd ligand. The electrochemical data for clusters 2 and 3 are discussed with respect to the reported redox chemistry for this genre of tricobalt cluster and the bpcd ligand.     

Synthesis and the crystal and molecular structure of two modifications of bis(1,10-phenanthroline)trinitratoerbium(III) Er(NO3)3(Phen)2

Two crystalline modifications (I and II) of the phenanthroline complex of erbium nitrate with the same chemical composition, Er(NO₃)₃(Phen)₂, are synthesized by a procedure similar to that used for preparing the phenanthroline complexes of europium nitrate. The crystal structures of these modifications are determined using X-ray diffraction. Crystals of compound I belong to the isostructural family Ln(NO₃)₃(Phen)₂ (Ln = La-Lu). Crystals of compound II are isostructural to those of modification II (new phase) of the Eu(NO₃)₃(Phen)₂ compound. Crystals of I and II are monoclinic, space group C2/c, and Z = 4. The unit cell parameters are as follows: a = 11.126 Å, b = 17.815 Å, c = 12.976 Å, β = 100.45°, and V = 2529 ų for modification I and a = 9.459 Å, b = 15.463 Å, c = 17.076 Å, β = 93.52°, and V = 2493 ų for modification II. The molecular complexes in the structures of compounds I and II are nearly identical. The mean lengths of the Er-N and Er-O bonds are equal to 2.500 and 2.466 Å in compound I and 2.508 and 2.457 Å in compound II, respectively. The difference between the structures of compounds I and II is associated with the difference between intermolecular interactions in the unit cell.     

Synthesis and structure of two crystalline modifications of Bis(1,10-Phenanthroline)trinitratoeuropium(III) Eu(NO3)3(Phen)2

Two crystalline modifications (I and II) of the phenanthroline complex of europium nitrate with the same chemical composition, Eu(NO₃)₃(Phen)₂, are synthesized under different conditions by varying the solvents, temperatures, and crystallization rates. The crystal structures of these modifications are determined using X-ray diffraction. Crystalline modifications I and II differ in the unit cell parameters and the positions of the complexes in the unit cell. The geometric characteristics of the complexes in the structures of compounds I and II differ insignificantly. Crystals of compound I belong to the isostructural family Ln(NO₃)₃(Phen)₂ (Ln = La-Lu). Crystals of compound II (new phase) are studied for the first time. Crystals of I and II are monoclinic, space group C2/c, and Z = 4. The unit cell parameters are as follows: a = 11.1555(10) Å, b = 17.9698(10) Å, c = 13.0569(10) Å, β = 100.507(10)°, and V = 2572.1(3) ų for modification I and a = 9.5153(10) Å, b = 15.4546(10) Å, c = 17.1763(10) Å, β = 93.451(10)°, and V = 2521.3(3) ų for modification II. The difference between the molecular complexes in the structures of compounds I and II is revealed by the superposition method. Complexes II are arranged along the C ₂ axis and are statistically disordered with respect to this axis.     

CO replacement in Ru3(CO)12 by 2,3-bis(diphenylphosphino)maleic anhydride (bma). X-ray structures of Ru3(CO)10(bma)·H2O and

Thermolysis of Ru₃(CO)₁₂ with 2,3-bis(diphenylphosphino)maleic anhydride (bma) in toluene solution gives the new compounds Ru₃(CO)₁₀(bma) (2), Ru₂(CO)₆(bma) (3), and (4). All compounds have been isolated and characterized in solution by IR and³¹P NMR spectroscopy. The solid-state structures of2, as the monohydrate, and4 were established by X-ray crystallography. Ru₃(CO)₁₀(bma)·H₂O crystallizes in the monoclinic space groupC2/c,a=12.741(2) Å,b=19.548(2) Å,c=32.973(4) Å, β=96.847(9)°,V=8154(2) ų,Z=8,d _calc=1.740 g cm^?3;R=0.046,R _w =0.051 for 2541 observed reflections withl>3σ(l). The bma ligand in2 is bound to the triruthenium frame in a bridging fashion, with equatorially disposed PPh₂ groups. The X-ray structure of2 reveals an extreme twisting of the maleic anhydride ring away from the plane defined by the plane of the three ruthenium atoms, along with a significant lengthening of the maleic anhydride C=C π bond. crystallizes in the monoclinic space groupP2₁/c,a=9.3113(5) Å,b=18.164(1) Å,c=20.097(1) Å, β-102.021(4)°,V=3324.5(3) ų,Z=4,d _calc=1.671 g cm^?3;R=0.024,R _w =0.030 for 3499 observed reflections withl>3σ(l). The presence of the μ₂ moiety and P?C (maleic anhydride) bond cleavage attendant in the formation of4 are confirmed by X-ray analysis. The relationship of the compounds3 and4 to the dimeric compounds Ru₂(CO)₆(bpcd) and [where bpcd=4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione] is discussed. Independent studies dealing with Ru₃(CO)₁₀(bma) (bridging isomer) have shown that cluster2 is stable in toluene solution at elevated temperature and does not afford compounds3 and4, suggesting the intermediacy of the putative chelating isomer of Ru₃(CO)₁₀(bma) (1) as the source of3 and4.     

X-Ray diffraction and IR-spectroscopic studies of UO2(n-C3H7COO)2(H2O)2 and Mg(H2O)6[UO2(n-C3H7COO)3]2

Single crystals of UO₂(n-C₃H₇COO)₂(H₂O)₂ (I) and Mg(H₂O)₆[UO₂(n-C₃H₇COO)₃]₂ (II) are synthesized. Their IR-spectroscopic and X-ray diffraction studies are performed. Crystals I are monoclinic, a = 9.8124(7) Å, b = 19.2394(14) Å, c = 12.9251(11) Å, β = 122.423(1)°, space group P2₁/c, Z = 6, and R = 0.0268. Crystals II are cubic, a = 15.6935(6) Å, space group $Pa\bar 3$ , Z = 4, and R = 0.0173. The main structural units of I and II are [UO₂(C₃H₇COO)₂(H₂O)₂] molecules and [UO₂(C₃H₇COO)₃]^? anionic complexes, respectively, which belong to AB ₂ ⁰¹ M ₂ ¹ (I) and AB ₃ ⁰¹ (II) crystal chemical groups of uranyl complexes (A = UO ₂ ²⁺ , B ⁰¹ = C₃H₇COO^?, and M ¹ = H₂O). A crystal chemical analysis of UO₂ L ₂ · nH₂O compounds, where L is a carboxylate ion, is performed.     

Synthesis and crystal structure of bis[2-[N-(2-chlorophenyl)formimidayl]-1-naphtholato]-(6Cl)copper(II)

The title compound, bis[2-[N-(2-chlorophenyl)formimidayl]-1-naphtholato]-(6Cl) copper(II), [Cu(C₁₇H₁₁NOCl)₂] (1) was synthesized and its crystal structure was determined. The Compound 1 is monoclinic, space group P2 ₁/c with a = 9.146(3) Å, b = 18.724(3) Å, c = 16.230(2) Å, β = 96.46(1)°, V = 2761.8(11) ų, Z = 4, D _c = 1.503 g cm^?3, μ(Mo Kα) = 1.020 mm^?1, R = 0.0606 for 2361 reflections [I > 2σ(I)]. In the title compound, the Cu atom is coordinated by an N₂O₂ donor set from the imine-phenol ligand in a slightly distorted square planar coordination geometry, with the two phenolate O atoms being deprotonated. The Cu–O bond lengths are 1.878(4) and 1.889(4) Å, the Cu–N bond lengths are 1.980(5) and 1.985(5) Å. The angles O1–Cu–N1 and O2–Cu–N2 are 90.96(19) and 90.72(19)°, respectively.     

Synthesis and structure of zirconium and 3d-transition metal phosphates M 0.5Zr2(PO4)3(M = Mn, Co, Ni, Cu, Zn)

Double zirconium and 3d-transition metal phosphates of the compositions M 0.5Zr2(PO4)3[M = Mn (I), Co (II), Ni (III), Cu (IV), Zn (V)] have been synthesized and the types of their structures have been refined. Compounds I, II, III, IV, and V are all monoclinic (sp. gr. P2₁/n, Z = 4) and have the unit cell parameters a = 12.390(3), 12.389(3), 12.385(3), 12.389(3), 12.389(2) Å; b = 8.931(4), 8.928(3), 8.924(4), 8.925(4), 8.929(3) Å; c = 8.843(3), 8.840(2), 8.840(3), 8.841(3), 8.842(2) Å, β = 90.55(1), 90.54(1), 90.53(1), 90.53(1), 90.54(1)°; V = 978.5, 977.7, 977.0, 977.4, 978.1 ų, respectively. All the structures have the {[Zr₂(PO₄)₃]^?}3_∞-type frameworks. The crystallographic data for 3d-transition and alkali earth metal phosphates described by the general formula M _0.5Zr₂(PO₄)₃ are compared.     

CO substitution in the mixed-metal clusters PhCCo2Ni(CO)6Cp and PhCCo2Mo(CO)8Cp by (Z)-Ph2PCH=CHPPh2. X-ray diffraction structures and proof of ligand bridging in PhCCo2Ni(CO)4[(Z)-Ph2PCH=CHPPh2]Cp and PhCCo2Mo(CO)6[(Z)-Ph2PCH=CHPPh2]Cp

The heterometallic tetrahedrane clusters PhCCo₂Ni(CO)₆Cp (1) and PhCCo₂Mo(CO)₈Cp (3) react with the unsaturated diphosphine ligand (Z)-Ph₂PCH=CHPPh₂ at elevated temperature to afford the corresponding phosphine-substituted clusters PhCCo₂Ni(CO)₄[(Z)-Ph₂PCH=CHPPh₂]Cp (2) and PhCCo₂Mo(CO)₆[(Z)-Ph₂PCH=CHPPh₂]Cp (4). Clusters 2 and 4 have been isolated by column chromatography and characterized in solution by IR and NMR (¹H and ³¹P) spectroscopies, and the solid-state structures of these clusters have been determined by X-ray crystallography. PhCCo₂Ni(CO)₄[(Z)-Ph₂PCH=CHPPh₂]Cp crystallizes in the triclinic space group P-l, a = 10.8142(7), b = 10.8994(6), c = 17.661(2) Å, α = 82.870(6), β = 86.149(7), γ = 64.493(5)^°, V = 1864.0(2) ų, Z = 2, D _cacl = 1.495 g/cm³; R = 0.0409, R _w = 0.0424 for 3147 observed reflections with I > 3σ(I). PhCCo₂Mo(CO)₆[(Z)-Ph₂PCH=CHPPh₂]Cp, as the hexane solvent, crystallizes in the monoclinic space group P2₁/c, a = 12.706(4), b = 17.367(3), c = 21.639(7) Å, β = 106.48(3)^°, V = 4579(1) ų, Z = 4, D _cacl = 1.478 g/cm³; R = 0.0605, R _w = 0.0724 for 1330 observed reflections with I > 3σ(I). The solid-state structures of 2 and 4 confirm a bridging coordination mode for the (Z)-Ph₂PCH=CHPPh₂ ligand, with adjacent cobalt centers being ligated by the ancillary phosphine ligand. The structural highlights of these new mixed-metal clusters are discussed relative to the homometallic tetrahedrane cluster PhCCo₃(CO)₇[(Z)-Ph₂PCH=CHPPh₂].     

Synthesis and Characterization of the Osmium Compound <Emphasis Type="Italic">cis</Emphasis>(CO)<Emphasis Type="Italic">–</Emphasis>ClOs(CO)<Subscript>2</Subscript>(bpcd)[C(O)Et]

Photochemical activation of the triosmium cluster Os₃(CO)₁₂ in CH₂Cl₂ solvent and ethylene, followed by treatment with the diphosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd), furnishes the new octahedral compound cis(CO)–ClOs(CO)₂(bpcd)[C(O)Et] in low yield. The title compound has been isolated and characterized in solution by IR and ¹H NMR spectroscopies, with the solid-state structure of cis(CO)–ClOs(CO)₂(bpcd)[C(O)Et] determined by X-ray diffraction analysis. cis(CO)–ClOs(CO)₂(bpcd)[C(O)Et] crystallizes in the triclinic space group P-1, a = 10.043(2), b = 11.455(2), c = 16.221(3) Å, α = 74.900(3)°, β = 76.150(3)°, γ = 76.221(2)°, V = 1718.2(5) ų, Z = 2, D _cacl = 1.717 Mg/m³; R = 0.0453, R _w = 0.0778 for 6703 observed reflections with I > 2σ(I). The presence of the chlorine and propanioyl groups in cis(CO)–ClOs(CO)₂(bpcd)[C(O)Et] is structurally confirmed, and the origin of the these groups from the reaction solvent and ethylene is discussed.     

Crystal structures and properties of isomers of 3,5-dinitro-(4-acetylphenyl)aminobenzoyl (p-bromophenyl)amide

The para and ortho isomers of 3,5-dinitro-(4-acetylphenyl)aminobenzoyl (p-bromophenyl)amide (I and II, respectively) are synthesized, and their physicochemical properties and structure are investigated. The para isomer I has a higher melting temperature and is less soluble in organic solvents as compared to the ortho isomer II. The electronic absorption spectra indicate that absorption for molecule I occurs at longer wavelengths than for molecule II. A correlation between the physicochemical properties and the crystal structures of compounds I and II is revealed. Crystals I · 0.5C₆H₆ are triclinic; the unit cell parameters are a = 11.760(2) Å, b = 13.958(3) Å, c = 15.012(3) Å, α = 108.01(2)°, β = 103.95(1)°, γ = 92.00(2)°, V = 2258.3(8) ų, space group $P\bar 1$ , and Z = 4. Crystals II are monoclinic; the unit cell parameters are a = 9.302(2) Å, b = 16.380(3) Å, c = 13.480(3) Å, β = 100.09(3)°, V = 2022.1(7) ų, space group P2₁/c, and Z = 4. Structures I · 0.5C₆H₆ and II are characterized by intramolecular and intermolecular hydrogen bonds.     

Reaction of 2,3-bis(diphenylphosphino)maleic acid-thioanhydride (bmata) with PhCCo3(CO)9. X-ray diffraction structure of {\text{Co}}_{\text{3}} ({\text{CO)}}_{\text{6}} [\mu _2 ,\eta ^2 ,\eta ^1 {\text{ - C(Ph)}}{\text{(O)](}}\mu _2 {\text{ - PPh}}_{\text{2}} )

The benzylidyne-capped cluster PhCCo₃(CO)₉ (1) reacts with the diphosphine ligand 2,3-bis(diphenylphosphino)maleic acid-thioanhydride (bmata) to afford ultimately the new cluster ${\text{Co}}_{\text{3}} ({\text{CO)}}_{\text{6}} [\mu _2 ,\eta ^2 ,\eta ^1 {\text{ - C(Ph)}}{\text{(O)](}}\mu _2 {\text{ - PPh}}_{\text{2}} )$ (3) in low yield under thermolysis conditions or by Me₃NO activation of PhCCo₃(CO)₉. The intermediate cluster compound PhCCo₃(CO)₇(bmata) (2) has been confirmed by IR spectroscopy and is shown to give ${\text{Co}}_{\text{3}} ({\text{CO)}}_{\text{6}} [\mu _2 ,\eta ^2 ,\eta ^1 {\text{ - C(Ph)}}{\text{(O)](}}\mu _2 {\text{ - PPh}}_{\text{2}} )$ upon heating. Cluster 3 has been isolated and characterized in solution by IR and ³¹P NMR spectroscopies, and the solid-state structure of 3 was established by X-ray diffraction analysis. ${\text{Co}}_{\text{3}} ({\text{CO)}}_{\text{6}} [\mu _2 ,\eta ^2 ,\eta ^1 {\text{ - C(Ph)}}{\text{(O)](}}\mu _2 {\text{ - PPh}}_{\text{2}} )$ crystallizes in the triclinic space group P ${\bar 1}$ , a = 11.6053(8) Å, b = 11.8438(8) Å, c = 15.099(1) Å, α = 105.169(5)^○, β = 90.530(5)^○, γ = 104.976(6)^○, V = 1928.5(2) ų, Z = 2, and d _calc = 1.578; R = 0.0442, R _w = 0.481 for 2591 observed reflections with I > 3σ (I). The cyclic voltammetric properties of 3 have been investigated and are contrasted with the related bma-derived cluster ${\text{Co}}_{\text{3}} ({\text{CO)}}_{\text{6}} [\mu _2 ,\eta ^2 ,\eta ^1 {\text{ - }}{\text{(O)OC(O)](}}\mu _2 {\text{ - PPh}}_{\text{2}} )$ .     

Crystal structure of double vanadates Ca9 R(VO4)7. II. R = Tb, Dy, Ho, and Y

Crystal structures of the compounds Ca₉ R(VO₄)₇ (R = Tb (I), Dy (II), Ho (III), and Y (IV) have been studied by the method of the full-profile analysis. All the compounds are crystallized in the trigonal system (sp. gr. R 3 c, Z = 6) with the unit-cell parameters (I) a = 10.8592(1), c = 38.035(1), V = 3884.2(2) ų; (II) a = 10.8564(1), c = 38.009(1) Å, V = 3879.6(2) ų, (III) a = 10.8565(1) and c = 37.995(1) Å, V = 3878.3(2) ų, and (IV) a = 10.8588(1), c = 37.995(1) Å, V = 3879.9(2) ų. In structures I–IV, rare earth and calcium cations occupy three positions—M(1), M(2), and M(5). Rare earth cations occupy the R ³⁺ positions almost in the same way: 2.7–2.6(2) cations in the M(1) position; 2.7–2.3(2) cations in the M(2) position, and 0.6–1.0(1) cation in the M(5) position. At the same time, the occupancy of the M(5) position regularly increases with a decrease of the R ³⁺ radius.     

Synthesis and structural study of 1-(N,N-diethylamino)-2,2-bis(2-nitrophenylthio)ethene

The synthesis, variable temperature NMR spectra, and crystal structures of two crystalline forms, 2a and 2b, of the enamine 1-(N,N-diethylamino)-2,2-bis(2-nitrophenylthio)ethene have been obtained. Both forms crystallize in the monoclinic space group P2₁/a. The two phases have similar molecular structures but possess different intermolecular C–H······O hydrogen bonding interactions. Both forms exhibit disorder within the NEt₂ fragment at 298 K: sufficient disorder persisted with 2a (orange needles) down to 100 K to make the geometric parameters pertaining to the enamine fragment unreliable. The disorder was effectively eliminated on cooling 2b down (red colored blocks) to 150 K. Cell dimensions for the 2a-phase are at 100 K: a = 11.1030(4) Å, b = 15.1325(7) Å, c = 12.4504(7) Å, β = 114.606(3)°, while for the 2b-phase at 150 K, a = 15.5206(4) Å, b = 7.6958(2) Å, c = 15.7137(3) Å, β = 92.580(7)°. The C–N bond length in the β-form at 150 K of 1.335(3) Å indicates considerable double bond character: the rotational barrier of the C–N bond in CDCl₃ was calculated to be 52.4 kJ mol^?1.     

Site-selective ligand substitution in CoRu(CO)7(μ-PPh2) using (Z)-Ph2PCH=CHPPh2 and reactivity of DMAD with CoRu(CO)5[(Z)-Ph2PCH=CHPPh2](μ-PPh2). X-ray structures of CoRu(CO)5[(Z)-Ph2PCH=CHPPh2](μ-PPh2) and CoRu(CO)3(μ-CO)[(Z)-Ph2PCH=CHPPh2] [μ, η3-Ph2PC(CO2Me)C(CO2Me)]

The heterometallic complex CoRu(CO)₇(μ-PPh₂) (1) reacts with the diphosphine ligand (Z)-Ph₂PCH=CHPPh₂ under both thermolysis and Me₃NO activation to furnish CoRu(CO)₅[(Z)-Ph₂PCH=CHPPh₂](μ-PPh₂) (2) in good yield. Treatment of 2 with dimethyl acetylenedicarboxylate (DMAD) at elevated temperature leads to the formal insertion of the DMAD ligand into the Co–phosphido bond and formation of the metallocyclic compound CoRu(CO)₃(μ-CO)[(Z)-Ph₂PCH=CHPPh₂][μ,η³-Ph₂PC(CO₂Me)C(CO₂Me)] (3) that contains a 5e^? alkenylphosphine moiety. These new CoRu compounds have been isolated by chromatography and fully characterized in solution by IR and NMR (¹H and ³¹P) spectroscopies, and the solid-state structures of both 2 and 3 have been determined by X-ray diffraction analysis. CoRu(CO)₅[(Z)-Ph₂PCH=CHPPh₂](μ-PPh₂) crystallizes in the monoclinic space group P2 ₁/n, a = 11.493(8), b = 20.24(1), c = 17.04(1) Å, β = 91.03(1)°, V = 3964(5) ų, Z = 4, D _calc = 1.477 Mg/m³; R = 0.0475, R _w = 0.1054 for 5120 observed reflections with I > 2σ (I). CoRu(CO)₃(μ-CO)(Z)-Ph₂PCH=CHPPh₂][μ,η³-Ph₂PC(CO₂Me)C(CO₂Me)], as the CH₂Cl₂ solvate, crystallizes in monoclinic space group P2 ₁/c, a = 17.0307(9) Å, b = 11.2124(6) Å, c = 24.083(1) Å, β = 97.755(1)°, V = 4556.8(4) ų, Z = 4, D _calc = 1.579 Mg/m³; R = 0.0379, R _w = 0.0609 for 10774 observed reflections with I > 2σ(I). The regioselective coordination of the (Z)-Ph₂PCH=CHPPh₂ ligand to the two equatorial sites of the ruthenium center in 2 and the presence of the metallocyclic alkenylphosphine ligand in 3 are confirmed by the structural studies. The regiochemistry found in the coordination of (Z)-Ph₂PCH=CHPPh₂ to 1 is contrasted with the related diphosphine ligands bma and bpcd, while the DMAD insertion reactivity with 2 is discussed relative to alkyne reactions reported for the parent compound CoRu(CO)₇(μ-PPh₂).     

Reaction of o-phenylenediamine with 2,3-dichloromaleic anhydride: synthesis of N-substituted maleimide derivatives and 2,3-dichloropyrrolo[1,2-a]benzimidazol-1-one. X-ray structures of 2,3-dichloro-N-o-C6H4(NH2)maleimide and N, N′-o-C6H4-bis(2,3-dichloromaleimide)

Refluxing equimolar amounts of 2,3-dichloromaleic anhydride and o-phenylenediamine in toluene affords the three compounds 2,3-dichloro-N-o-C₆H₄(NH₂)maleimide (1), N,N′-o-C₆H₄-bis(2,3-dichloromaleimide) (2), and 2,3-dichloropyrrolo[1,2-a]benzimidazol-1-one (3). Under these conditions the former compound is observed as the major product. Repeating the same reaction in the presence of added PTSA furnishes the heterocyclic compound 2,3-dichloropyrrolo[1,2-a]benzimidazol-1-one, as the major product. Treatment of compound 1 with PTSA, coupled with water removal, gives compound 3 in near quantitative yield and confirms the intermediacy of 1 en route to 3. The new compounds 1–3 have been isolated by column chromatography and characterized in solution by spectroscopic methods. The molecular structures of the maleimide-substituted compounds 1 and 2 were determined by X-ray crystallography. 2,3-Dichloro-N-o-C₆H₄(NH₂)maleimide crystallizes in the monoclinic space group P2₁/c, a = 20.693(8) Å, b = 5.712(2) Å, c = 8.787(4) Å, β = 92.819(7)°, V = 1037.3(7) ų, Z = 4, and d _calc = 1.646 Mg/m³; R = 0.0604, R _w = 0.1140 for 1354 reflections with I > 2 σ (I), with N,N′-o-C₆H₄-bis(2,3-dichloromaleimide) crystallizing in the triclinic space group P?1, a = 7.9509(4) Å, b = 10.2532(6) Å, c = 12.1126(7) Å, α = 82.637(1)°, β = 87.799(1)°, γ = 71.634(1)°, V = 929.42(9) ų, Z = 2, and d _calc = 1.651 Mg/m³; R = 0.0499, R _w = 0.1545 for 1977 reflections with I > 2σ (I).     

Molecular and crystal structures of 1R,4S-2-(4-carbomethoxy)benzylidene-n-menthan-3-one

The molecular and crystal structures of chiral 1R,4S-2-(4-carbomethoxy)benzylidene-n-menthan-3-one (I) are determined by X-ray diffraction analysis. Crystals I are orthorhombic; at 20°C: a = 11.961(3) Å, b = 26.453(8) Å, c = 5.400(2) Å, space group P2₁2₁2₁, and Z = 4 (C₁₉H₂₅O₃). In molecule I, the cyclohexanone ring with the axial methyl and isopropyl substituents adopts a chair conformation. It is found that the enone and arylidene fragments of compound I have a substantially nonplanar structure. The shortened intramolecular contacts between atoms of the arylidene grouping and the α fragment of the cyclohexanone ring and their associated distortions of bond angles at the sp ² carbon atoms are the common structural features of 2-arylidene-n-menthan-3-ones irrespective of the stereochemical configuration of the C(4) chiral center.     

N-isopropyl-2-(isopropylamino)troponiminate complexes of lithium and calcium

The synthesis and structures of [(i-Pr)₂ATI]Li₂(thf)(I)(1) and [(i-Pr)₂ATI]Ca(thf)₂(I)₂Li₂(thf)₂-[(i-Pr)₂ATI] (2) (where [(i-Pr)₂ATI]=N-isopropyl-2-(isopropylamino)troponiminate) have been described. The lithium atoms in compounds1 and2 occupy positions above and below the plane of the aminotroponiminate ligand. The calcium atom in2 adopts a pseudo-octahedral geometry with two tetrahydrofurans occupying thetrans-positions. Compound1 crystallizes as dimeric units. Crystal data with MoKα at 193 K:1, C₁₇H₂₇ILi₂N₂O,a=13.217(2)Å,b=9.875(2)Å,c=16.410(4)Å, B=111.41(1)^o,V=1993.4(6)ų, a monoclinic space groupP2₁/n,Z=4,R=0.029;2, C₄₂H₇₀CaI₂Li₂N₄O₄,a=911.390(2)Å,b=30.880(4)Å,c=13,465(2)Å, B=93.85(1)^o,V=4724(1)ų, monoclinic space groupC2/c,Z=4,R=0.027.     

Molecular and crystal structures of 1R,4R-cis-2-(4-hydroxybenzylidene)-p-menthan-3-one

The molecular and crystal structures of chiral 1R, 4R-cis-2-(4-hydroxybenzylidene)-p-menthan-3-one (I) are determined by X-ray diffraction analysis. Single crystals of I are orthorhombic, a = 8.997(2) Å, b = 11.314(2) Å, c = 14.847(3) Å, V = 1511.3(5) ų, Z = 4, and space group P2₁2₁2₁. The cyclohexanone ring in molecules of compound I has a chair-type conformation with the axial methyl and equatorial isopropyl groups. The enone and benzylidene groupings are nonplanar. The considerable distortion of bond angles at the sp ² carbon atoms of the benzylidene grouping and the puckering parameters of the cyclohexanone ring in the structure of I are close to those observed for the previously studied compound with the p-methoxy substituent. In the crystal, molecules I are linked by very short intermolecular hydrogen bonds .     

Synthesis and crystal structure of new double indium phosphates M 3 I In(PO4)2 (M I = K and Rb)

Double potassium indium and rubidium indium phosphates K₃In(PO₄)₂ (I) and Rb₃In(PO₄)₂ (II) are synthesized by solid-phase sintering at T = 900°C. The compounds prepared are characterized by X-ray powder diffraction (I and II), X-ray single-crystal diffraction (II), and laser-radiation second harmonic generation. Structure I is solved using the Patterson function and refined by the Rietveld method. Both compounds crystallize in the monoclinic crystal system. For crystals I, the unit cell parameters are as follows: a = 15.6411(1) Å, b = 11.1909(1) Å, c = 9.6981(1) Å, β = 90.119(1)°, space group C2/c, R _p = 4.02%, and R _wp = 5.25%. For crystals II, the unit cell parameters are as follows: a = 9.965(2) Å, b = 11.612(2) Å, c = 15.902(3) Å, β = 90.30(3)°, space group P2₁/n, R ₁ = 4.43%, and wR ₂ = 10.76%. Structures I and II exhibit a similar topology of the networks which are built up of { In[PO₄]₂} (I) and { In₂[PO₄]₄} (II) structural units.