Crystal and molecular structures of (±)cadinene dihydrochloride (1) and (−)cadinene dihydrochloride (2)

Two compounds, racemic (±)cadinene dihydrochloride C₁₅H₂₆C1₂ (1) and (–)cadinene dihydrochloride C₁₅H₂₆Cl₂ (2), prepared by treating germacrene D fromSolidago canadensis L, and sesquiterpene fraction of essential oil fromPinus silvestris L, respectively, with gas HCl were investigated. Compound (1) crystallizes in monoclinic system, but (2) in orthorhombic (Table 1). The structures were found by direct methods and were refined with full matrix least-squares techniques to R value of 0.039 and 0.044, respectively, for (1) and (2).     

Crystal structures of mixed ligand complexes containing saccharinate and nicotinamide: [Cu(saccharinato)2 (nicotinamide) (H2O)]⋅(H2O) and [M(nicotinamide)2 (H2O)4]⋅(saccharinate)2 (M = Ni2+, Co2+)

[M(saccharinato)₂(H₂O)₄] (M = Cu²⁺, Ni²⁺, Co²⁺) react with nicotinamide to form mixed ligand complexes, [Cu(saccharinato)₂(nicotinamide)(H₂O)](H₂O) (1) and [M(nicotinamide)₂(H₂O)₄](saccharinate)₂ (2: M = Ni²⁺; 3: M = Co²⁺), and their crystal structures have been determined by X-ray diffraction. In 1, the Cu²⁺ atom in an octahedral configuration is coordinated by two monodentate saccharinato ligands in the trans arrangement through the deprotonated ring nitrogens, by two bidentate nicotinamide ligands, one through the pyridyl ring nitrogen and the other through the amide oxygen, and by a water molecule, thus forming a nicotinamide-bridged one-dimensional extended structure. In the isomorphous complexes 2 and 3, the octahedral metal atom, which rides on a crystallographic center of symmetry, is coordinated by two monodentate nicotinamide ligands through the ring nitrogens and four water molecules to form a discrete [M(nicotinamide)₂(H₂O)₄]^{2 +} structural unit, which captures up and down two saccharinate ions, each through three hydrogen bonds: two hydrogen bonds between two water ligands and the ring N and the carbonyl O atoms and one between the amide N of the nicotinamide ligand and the carbonyl O.     

Self-assemblies of Ni(II) with phenanthroline and maleate anions: [Ni(H2O)3(phen)L] ⋅ H2O (1) and [Ni(H2O)2(phen)L] ⋅ 2H2O (2) with H2L = maleic acid

The complex [Ni(H₂O)₃(phen)(C₄H₂O₄)] H₂O (1), which was obtained by reaction of phenanthroline, Ni(NO₃)₂ 6H₂O, and maleic acid in CH₃OH/H₂O at pH = 7.05, crystallized in the monoclinic space group P2₁ (no. 4) with cell dimensions: a = 9.350(1) Å, b = 7.631(1) Å, c = 12.821(1) Å, = 106.25(1), and D _calc = 1.607 g/cm³ for Z = 2. The Ni atoms are each octahe drally coordinated by one chelating phen ligand, three H₂O molecules and one monodentate maleato ligand to form [Ni(H₂O)₃(phen)(C₄H₂O₄)] complex molecules with d(Ni–O) = 2.038–2.090 Å, d(Ni–N) = 2.066, 2.089 Å. The formed complex molecules are, via the intermolecular hydrogen bonds, assembled into columnar 1D chains. Interdigitation of the chelating phen ligands of the neighboring chains leads to 2D layers and the crystal H₂O molecules are hydrogen bonded to the oxygen atoms of the maleate not coordinated to the Ni atom. However, reaction of NiCO₃, phen, and maleic acid in CH₃OH/H₂O at pH = 6.33 afforded [Ni(H₂O)₂(phen)(C₄H₂O₄)] 2H₂O (2), which crystallized in the triclinic space group (no. 2) with cell dimensions: a = 7.971(1) Å, b = 8.237(1) Å, c = 13.304(1) Å, = 81.005(6)°, = 87.877(8)°, = 78.322(8)°, and D _calc = 1.671 g/cm³ for Z = 2. The Ni atoms are each octahedrally coordinated by two N atoms of one phen ligand and four O atoms of two H₂O molecules and two bis–monodentate maleato ligands with d(Ni–O) = 2.041–2.120 Å and d(Ni–N) = 2.095 Å. The Ni atoms are bridged by the maleato ligands to generate 1D ¹ [Ni(H₂O)₂(phen)(C₄H₂O₄)_2/2] chains along [100]. The supramolecular assemblies of the 1D chains via – stacking inter- actions result in thick 2D layers parallel to (001), between which the noncoordinating H₂O molecules are sandwiched. The paramagnetic [Ni(H₂O)₂(phen)(C₄H₂O₄)_2/2] 2H₂O (2) obeys the Curie–Weiss law _m(T-) = 1.139cm³ mol^–1 K with the Weiss constant = –0.95 K.     

Synthesis and crystallographic characterization of [Cd(OH2)2 (μ-Br)4 (Cd(2-hydroxyethyl sulfide) (μ-Br))2]n

The reaction of equal millimolar quantities of CdBr₂ and 2-hydroxyethyl sulfide in 31 CH₃CNCH₃OH produced [Cd(OH₂)₂(Br)₄ (Cd(2-hydroxy ethyl sulfide) (-Br))₂]_n. The compound crystallizes as a bromide-bridged polymer with hydrogen bonding interactions between the polymeric chains. Each of the two unique metal centers has a distorted octahedral geometry. The thioether ligand is bidentate to one cadmium position with one alcoholic terminus uncoordinated. The uncoordinated portion of the molecule is disordered with each conformation participating in slightly different hydrogen bonding environments. The other unique cadmium center is coordinated to four bridging bromides and twotrans water molecules.     

Synthesis and structural analysis of (μ-SCH2CH2CH2S-μ)Fe2(CO)5(2-C5H4NPPh2)

Treatment of (μ-SCH₂CH₂CH₂S-μ)Fe₂(CO)₆ with equimolar 2-C₅H₄NPPh₂ in the presence of Me₃NO·2H₂O in CH₂Cl₂/MeCN solutions gave the title complex (μ-SCH₂CH₂CH₂S-μ)Fe₂(CO)₅(2-C₅H₄NPPh₂) in 76% yield. The title complex was characterized by spectroscopy as well as by single crystal X-ray diffraction analysis. The molecular structure consists of a butterfly [Fe₂S₂] cluster with propane, five carbonyls, and 2-C₅H₄NPPh₂. In the crystal packing diagram, intermolecular C–H···O hydrogen bonds between phenyl and carbonyl groups stabilize the solid state.     

Synthesis and crystal structure of (CN3H6)2[UO2(OH)2(NCS)]NO3 and β-Cs3[UO2(NCS)5]

Compounds (CN₃H₆)₂[UO₂(OH)₂(NCS)]NO₃ (I) and β-Cs₃[UO₂(NCS)₅] (II) are synthesized and studied by IR spectroscopy and single-crystal X-ray diffraction. I and II crystallize in the orthorhombic system. For I, a = 12.2015(13) Å, b = 7.3295(8) Å, c = 16.310(2) Å, space group Pnma, Z = 4, and R = 0.0327; for II, a = 21.7891(6) Å, b = 13.5120(3) Å, c = 6.8522(2) Å, space group Pnma, Z = 4, and R = 0.0268. In structure I, complex groups form infinite chains [UO₂(OH)₂(NCS)] _n ^n? belonging to the AM ₂ ² M ¹ crystal chemical group of uranyl complexes (A = UO ₂ ²⁺ , M ² = OH^?, and M ¹ = NCS^?). The main structural elements of crystals II are mononuclear [UO₂(NCS)₅]^3? groups belonging to the AM ₅ ¹ group of uranyl complexes (A = UO ₂ ²⁺ and M ¹ = NCS^?). In I and II, uranium-containing complexes are connected with outer-sphere cations by electrostatic interactions, and in I a system of hydrogen bonds also contributes to their binding. Specific features of the packing of complex [UO₂(NCS)₅]^3? groups in the structures of two modifications of Cs₃[UO₂(NCS)₅] are discussed.     

Crystal and Molecular Structures of 2-Amino-4-Nitrobenzoic Acid and Its Cocrystals with 2,2′-Bipyridine (2/1) and Bis(pyridin-2-yl)ketone (1/1)

Abstract  

The eight-membered {···HOC=O}₂ synthon featured in the crystal structure of 2-amino-4-nitrobenzoic acid (1) is replaced by carboxylic acid···N-pyridine hydrogen bonds in its cocrystals with 2,2′-bipyridine (2/1; 2) and bis(pyridin-2-yl)ketone (1/1; 3) indicating the robust nature of the latter synthon. Disruption of the three-dimensional architecture based on O–H···O and N–H···O(nitro) hydrogen bonds in (1) is evident in the cocrystals which form supramolecular tubes (2) and chains (3) based on O–H···N and N–H···O hydrogen bonding. Compound (1) crystallizes in the monoclinic space group P2₁/n with a = 3.6291(1) ?, b = 7.7339(3) ?, c = 26.561(1) ?, β = 91.385(2)°, and Z = 4. Compound (2) crystallizes in the monoclinic space group C2/c with a = 27.562(3) ?, b = 6.8300(6) ?, c = 12.923(1) ?, β = 110.593(5)°, and Z = 4. Compound (3) crystallizes in the monoclinic space group P2₁/c with a = 3.795(3) ?, b = 12.024(8) ?, c = 35.65(2) ?, β = 92.131(6)°, and Z = 4 (determined from synchrotron data).     

Reaction of trimethylaluminum and trimethylgallium with bifunctional amines: Syntheses and molecular structures of [Me2Al−N(CH2CH2)2−C−(OCH2)2]2 and [Me2Ga−N(Si(H)Me2)2]2

The crystalline products [Me₂Al–N(CH₂CH₂)₂–C–(OCH₂)₂]₂ (I) and [Me₂Ga–N(Si(H)Me₂)₂]₂ (II) were prepared from reactions of trimethylaluminum and trimethylgallium with 1,4-dioxa-8-azaspiro[4.5]-decane and 1,1,3,3-tetramethyldisilazane, respectively, in toluene. The organoaluminum dimer crystallizes in the monoclinic space groupP2₁/c with unit cell parametersa=8.970(2) ,b=9.683(2) ,c=12.833(3) , =103.18(2)°,V=1085.3(3) ³, andD _calcd=1.22 g cm^–3 forZ=2. Least-squares refinement based on 935 observed reflectionsI>3(I) in the range 3.5°<2<45.0° led to a finalR factor of 0.033 (R _w =0.041). The dimeric organosilazagallium crystallizes in the triclinic space group with unit cell parametersa=7.636(2) ,b=9.168(2) ,c=9.466(3), =72.81(2)°, =87.94(2)°, =69.90(2)°,V=593.0(3) ³, andD _calcd=1.30 g cm^–3 forZ=1. Least-squares refinement based on 1661 observed reflectionsI>3(I) in the range 3.5°<2<48.0° led to a finalR factor of 0.055 (R _w =0.070). Both compoundsI andII reside about a crystallographic center of symmetry and contain a planar M₂N₂ (M=Al forI, Ga forII) four-membered ring withI having an Al...Al contact of 2.801 .     

Synthesis and structure of (H2O·HBF4)2(18-crown-6)

The title compound has been prepared by the addition of fluoroboric acid to 18-crown-6 in toluene. The compound crystallizes in the triclinic space group P¯1 witha=7.341(2),b=8.364(2),c=10.631(3)Å,=71.48(2),=67.91(2), =67.94(2)°, andD _c =1.44 g cm^–3 forZ=1. The final conventionalR value was 0.079 based on 1575 observed reflections. The molecule resides on a center of inversion. The (H₂O·HBF₄) moieties are best viewed as fluoroboric acid monohydrate molecules hydrogen bonded to the crown ether, one above and one below the plane of the crown. The FO(water) hydrogen bond separation is 2.474(5)Å, and the O(crown)O(water) separations are 2.834(5) and 2.841(6) Å. The oxygen atoms of the crown ether are planar to 0.23 Å.     

Syntheses and Crystal Structures of Two CuII Coordination Isomers [Cu(pmt)2] · 4H2O (1) and {[Cu(pmt)2] · 2H2O} n (2)

Abstract  A pair of Cu^II coordination isomers [Cu(pmt)₂] · 4H₂O (1) and {[Cu(pmt)₂] · 2H₂O} _n (2) [Hpmt = 2-(2-pyridylmethylamino) ethanesulfonic acid] have been prepared by reaction of the same proportion CuCl₂ · 2H₂O and Hpmt but with different experimental methods in water–methanol mixed solution, and were characterized by X-ray diffraction, elemental analysis, IR spectrum. X-ray analysis indicates that complex (1) is a mononuclear complex in which two deprotonated pmt ligands coordinate in a facial tridentate arrangement about the Cu^II atom. While complex (2) is a coordination polymer, in which four N atoms of pmt ligands coordinate to one Cu^II atom but its sulfonate O atoms bond to adjacent Cu^II atom. Thus 12-membered rings (–Cu–N–C–C–S–O–)₂ are obtained between two neighbouring Cu^II atoms and they connect one another to form this new polymer. Crystal data: [Cu(pmt)₂] · 4H₂O (1), Mr = 566.10, monoclinic, P2 ₁/c, a = 9.1950(8) ?, b = 11.5093(10) ?, c = 11.2304(10) ?, β  = 105.5550(10)°, Z = 2, V = 1144.96(17) ?³, R ₁  = 0.0407, wR ₂  = 0.1242 [I > 2σ (I)]; {[Cu(pmt)₂] · 2H₂O} _n (2), Mr = 530.07, triclinic, P-1, a = 7.6165(19) ?, b = 8.806(2) ?, c = 9.592(4) ?, α = 104.933(4)°, β = 106.732(4)°, γ = 109.503(3)°, Z = 1, V = 534.2(3) ?³, R ₁ = 0.0470, wR ₂ = 0.1082 [I > 2σ(I)]. Index Abstract  A pair of Cu^II coordination isomers [Cu(pmt)₂] · 4H₂O (1) and {[Cu(pmt)₂] · 2H₂O} _n (2) [Hpmt = 2-(2-pyridylmethylamino) ethanesulfonic acid] have been prepared by reaction of the same proportion CuCl₂ · 2H₂O and Hpmt but with different experimental methods in water–methanol mixed solution.      

Structural study of nitrovinylindoles: (I) 2-methyl-3-(2′-methyl-2′-nitrovinyl)indole and (II) 3-(2′-nitrovinyl)indole

Compound (I) is 2-methyl-3-(2-methyl-2-nitrovinyl)indole, C₁₂H₁₂N₂O₂,M _r=216.24, monoclinic,P2₁/n,a=16.710(1),b=7.627(1),c=17.646(1) Å,=104.8(1)°,V=2174.7(1) ų,Z=8.D _x=1.321 g cm^–3, MoK, =0.71073 Å,=0.858 cm^–1,F(OOO)=912, room temperature,R=0.061 for 1956 observed reflections. Compound (II) is 3-(2-nitrovinyl)indole, C₁₀H₈N₂O₂,M _r=188.18, monoclinic,P2₁/n,a=10.178(1),b=10.608(1),c=8.411(1) Å,=105.5(2)°,V=875.0(1) ų,Z=4,D _x=1.4284 g cm^–3, CuK, =1.5418 Å,=8.068 cm^–1,F(000)=392, room temperature,R=0.040 for 1330 observed reflections. Compounds (I) and (II) have a similar geometry, the only significant difference lying in the rotation of the nitrovinyl chain. This feature could be responsible for the difference in biological activity. In both compounds, the molecules are associated, forming charge-transfer complexes.     

Structure,magnetic and IR studies of copper(II) diphenylphosphate dihydrate,Cu(DPhP)2·(H2O)2

The title compound has been synthesized, and characterized by means of X-ray, magnetic, and IR-spectroscopic measurements.The crystals of Cu(DPhP)₂(H₂O)₂(DPhP=diphenylphosphate) are monoclinic, space groupI2/c witha=24.126(6),b=8.510(2),c=12.333(3) Å,=90.73(5)° andZ=4. The structure was solved by the heavy-atom technique, and refined by full-matrix least-squares calculations to a finalR of 0.040 for 1494 reflections.The complex is centrosymmetric, and the Cu atom at a center of symmetry is four-fold coordinated with two oxygen atoms from two phosphate groups and two water molecules. The coordination about the Cu atom is square-planar, with Cu-O and Cu-O(W) distances 1.926(3) and 1.912(3) Å, respectively.The O(2) phosphate oxygen is an acceptor of two H bonds; one of them is an intramolecular O(W)-H(2)O(2) of 2.714(4) Å, and the other is an intermolecularO(W)-H(1)O(2ⁱ) of 2.667(4) Å. Their presence is also deduced from the IR spectrum of this compound at 3250 and 3000 cm^–1, respectively.The calculated magnetic moment value of 1.92 B.M. corresponds to that of the monomeric copper(II) complexes including those of some alkyl phosphates.     

Crystal Structures and Properties of Bis(2-Aminopyrimidine-N-)-Bis(Thiocyanato-N)Zinc(II) and Catena-[2-Aminopyrimidine-N- (μ-Thiocynanto-S,N)(Thiocyanato-S)Cadmium(II)]

Abstract  

Complexes [Zn(NCS)₂(2-AMP)₂] (2-AMP = 2-aminopyrimidine) 1 and [Cd(SCN)₂(2-AMP)₂]_n 2 are prepared and characterized by X-ray crystallographic methods. 1 crystallizes in the monoclinic, space group C2/c, with a = 13.5761(14), b = 8.3330(10), c = 13.5962(15) ?, β = 99.5450(10)°, V = 1516.8(3) ?³, Z = 4. In 1, the zinc atom is coordinated by four N atoms from two AMP and two NCS⁻. 2 crystallizes in the monoclinic, space group C2/c, with a = 9.7259(11), b = 19.332(2), c = 8.2149(9) ?, β = 99.817(2)°, V = 1522.0(3) ?³, Z = 4. Complex 2 is made up of 1D chains along a-axis. Each Cd is attached to four NCS⁻ bridges and two pendant 2-AMP ligands.     

Regiospecific ligand addition to the donor–acceptor compound Ru2(CO)6(bpcd): syntheses and X-ray diffraction structures of Ru2(CO)5L(bpcd) and Ru2(CO)5L[μ-C=C(PPh2)C(O)CH2C}(O)](μ2-PPh2) (where L = PMe3 and tBuNC)

Thermal and Me₃NO-assisted activation of the donor–acceptor complex Ru₂(CO)₆(bpcd) (1) [where bpcd = 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione] with PMe₃ or ^tBuNC affords the mono-substituted complexes Ru₂(CO)₅L(bpcd), as a result of regiospecific ligand attack at the diphosphine-substituted ruthenium center. Solution NMR measurements (¹H and ³¹P) reveal that the PMe₃ derivative exists as a noninterconverting mixture of axial (3a) and equatorial (3e) isomers, with the only the equatorial isomer being observed for Ru₂(CO)₅(^tBuNC)(bpcd) (5). Near-UV irradiation of 1 in the presence of added ligand yields Ru₂(CO)₅L(bpcd), in addition to the known ₂-phosphido complex Ru²(CO)⁶ [-C=C(PPh₂)C(O)CH₂C(O)](₂-PPh₂) (2) and the corresponding phosphido-substituted complexes Ru²(CO)_5L[-{C =C(PPh₂)C(O)CH₂C}(O)]₂-PPh₂)[4 (L = PMe₃); 6 (L = ^tBuNC)]. As with compounds 3a, 3e, and 5, both 4 and 6 exhibit ligand attachment at the diphosphine-substituted ruthenium center. The molecular structures of 3e, 4, 5, and 6 were determined by X-ray crystallography. 3e, as the 1/2 C₆H₆ solvate, crystallizes in the monoclinic space group C2/c: a = 40.573(3) Å, b = 10.2663(9) Å, c = 18.347(1) Å, = 95.371(6)°, V = 7609(1) ų and Z = 8; 4, crystallizes in the monoclinic space group P2₁/n: a = 10.8241(8) Å, b = 18.074(1) Å, c = 19.194(1) Å, = 96.968(6)°, V = 3727.3(5) ų, and Z = 4; 5, as the 1/2CH₂Cl₂ solvate, crystallizes in the monoclinic space group C2/c: a = 40.955(3) Å, b = 9.7230(6) Å, c = 20.542(1) Å, = 106.596(5)°, V = 7839.2(9) ų, and Z = 8; 6, as the 1/2C₅H₁₂ solvate, crystallizes in the monoclinic space group P2₁/c: a = 21.773(2) Å, b = 10.907(3) Å, c = 18.744(4) Å, = 114.68(1)°, V = 4045(1) ų, and Z = 4. The site occupied by the PMe₃ and ^tBuNC ligands in these compounds is discussed relative to the steric size/electronic properties of the ancillary ligand and its interaction with the bpcd ligand.     

Differential metathesis reactions of 2,2′-bipyridine and 1,10-phenanthroline complexes of cobalt(II) and nickel(II): cocrystallization of ionization isomers {[cis-Ni(phen)2(H2O)2][cis-Ni(phen)2(H2O)Cl]} (PF6)3⋅4.5H2O, and a synthetic route to asymmetric tris-substituted complexes

Addition of ammonium hexafluorophosphate to aqueous solutions of M(chelate)Cl₂ [chelate = 2,2-bipyridine and 1,10-phenanthroline, M = Co(II) and Ni(II)] produce different metathesis products. Tris-substituted chelate complexes are produced in the case of bipyridine; however {[cis-M(phen)₂Cl(H₂O)][ cis-M(phen)₂(H₂O)₂]}(PF₆)₃4.5H₂O, a unique example of cocrystallized ionization isomers, is produced with phenanthroline. Extended hydrogen bonding interactions connect [M(phen)₂Cl(H₂O)]⁺ and [M(phen)₂(H₂O)₂]²⁺ cations in the crystal lattice. Because metathesis reactions using phenanthroline produce disubstituted complexes, the convenient synthesis of symmetric [Ni(phen)₃]²⁺ and asymmetric [Ni(phen)₂(5-nitrophenanthroline)]²⁺ is described.     

Synthesis and crystal structure of cyanocadmate clathrate with 2-methylimidazole (2-Meim): [Cd3(CN)6(2-Meim)2] ⋅ 2Me2SO

The cyanocadmate clathrate with 2-methylimidazole, [Cd₃(CN)₆(2-Meim)₂] 2Me₂SO, has been prepared and its crystal structure analyzed by X-ray diffraction method. This clathrate crystallizes in the orthorhombic system, space group Pbcn, with a = 13.237(3), b = 14.870(3), c = 14.698(3) Å, V = 2893.1(10) ų, Z = 4. The three-dimensional (3D) host framework is built of the cyanide bridges among two kinds of Cd ions, octahedral and tetrahedral in a ratio of 1:2. The octahedral Cd(1) center is linked to six tetrahedral Cd atoms; the tetrahedral Cd(2) center is linked to three octahedral Cd atoms and ligated by one 2-methylimidazole ligand. The novel host structure provides two types of channel, vacant distorted-diamond channel and rectangular channel which is occupied by dimethylsulfoxide guest molecule and 2-methylimidazole ligand coordinated to the tetrahedral Cd site.     

Synthesis and crystal structure of bis(carbamide)chromatoneptunyl NpO2CrO4 · 2[OC(NH2)2]

The crystal structure of the hexavalent neptunium complex NpO₂CrO₄ · 2[OC(NH₂)₂] is determined. The crystal data are a = 7.192(2) Å, b = 12.902(4) Å, c = 11.226(3) Å, β = 92.19(2)°, V = 1040.9(4) ų, space group P2₁/n, Z = 4, d _calcd = 3.223 g/cm³, R = 0.045, and R _w = 0.130. The coordination polyhedron of the Np atom is the pentagonal bipyramid whose equatorial plane is formed by the oxygen atoms of the chromate ions and carbamide molecules.     

Alkyne insertion and coupling reactions of methyl propiolate with the heterometallic dimers CoRu(CO)7(μ-PPh2) and CoRu(CO)5[(Z)-Ph2PCH = CHPPh2](μ-PPh2): X-ray diffraction structures of CoRu(CO)4(μ-CO)[μ-PPh2C(O)CH(CCO2Me)C(O)CHC (CO2Me)] and CoRu(CO)3(μ-CO)[(Z)-Ph2PCH = CHPPh2][μ-PPh2C(O)C(CO2Me)CH]

The reaction of the terminal alkyne methyl propiolate with the heterometallic dimers CoRu(CO)₇(μ-PPh₂) (1) and CoRu(CO)₅[(Z)-Ph₂PCH=CHPPh₂](μ-PPh₂) (2) has been investigated at 65^°C in toluene. In the reaction of 1, chromatographic purification afforded a minor band, from which the two species RuCo(CO)₄(μ-CO)[μ-PPh₂C(O)CHC(CO₂Me)] and RuCo(CO)₄(μ-CO)[μ-PPh₂CHC(CO₂Me)] were observed by ¹H NMR spectroscopy, and one major band, whose ¹H NMR spectrum revealed the presence of multiple species. The identity of one of the compounds in the major component has been established as that of CoRu(CO)₄(μ-CO)[μ-PPh₂C(O)CH(CCO₂Me)C(O)CHC(CO₂Me)] (3) by X-ray diffraction analysis. The solid-state structure of 3 confirms the double insertion of CO and head-to-head coupling of the methyl propiolate that accompanies the formation of this product. Compound 3 crystallizes in the triclinic space group P-1, a = 8.4035(4), b = 9.6721(5), c = 17.678(1) Å, α = 94.135(2), β = 103.318(2), γ = 101.336(2)^°, V = 1360.5(1) ų, Z = 2, D _calc = 1.732 Mg/m³; R = 0.0300, R _w = 0.0760 for 8630 reflections with I > 2σ(I). The ruthenium-bound diphosphine ligand in 2 exerts a controlling influence on the reaction with added alkyne insomuch as only the mono-insertion product CoRu(CO)₃(μ-CO)[(Z)-Ph₂PCH=CHPPh₂][μ-PPh₂C(O)C(CO₂Me)CH] (4) is formed as a single regioisomer. The molecular structure of 4 was established by X-ray diffraction analysis and 4 was found to crystallize in the monoclinic space group P2₁/c, a = 19.483(7), b = 11.905(4), c = 20.131(7) Å, β = 110.455(6)^°, V = 4375(3) ų, Z = 4, D _calc = 1.466 Mg/m³; R = 0.0961, R _w = 0.1683 for 6262 reflections with I > 2σ(I). The reactivity of methyl propiolate with 1 and 2 is compared with the known reactivity that has been reported for other alkynes.     

Reactions of [Mn2(μ-pyS)2(CO)6] (pySH=pyridine-2-thiol) with triphenylphosphine (PPh3), diphenylphosphine (PHPh2) and bis(diphenylphosphino)methane (dppm): X-ray crystal structure of [Mn(pyS)(η1-dppm)2(CO)2]

The dimeric complex [Mn₂(-pyS)₂(CO)₆] (1) reacted with 2 M equivalents of both PPh₃ and PHPh₂ to give the respective monomeric phosphine complexes [Mn(pyS)(L)(CO)₃][L = PPh₃ (2) and PHPh₂ (3)]; with 4 M equivalents of dppm, it yielded the complex [Mn(pyS)(¹-dppm)₂(CO)₂](4). An X-ray structure determination of 4 shows that it crystallizes in the monoclinic space group P2₁/n with a = 11.027(3), b = 24.984(7), c = 18.379(5) Å, = 99.870(8)°, V = 4988(2) ų, and Z = 4. The complex has an octahedral geometry with the chelating pyS ligand and two CO groups occupying the equatorial sites and the two monodentate dppm ligands lying in the trans positions.     

Structure of the adduct of bis(O,O′-diisopropyldithiophosphato) metal with pyridine: Ni[(iPrO)2PS2]2(py)2 and Cd[(iPrO)2PS2]2 (py)2(py = pyridine)

The crystal and molecular structures of the complex of [Ni{(iPrO)₂dtp}₂(py)₂] and [Cd{(iPrO)₂dtp}₂(py)₂] (dtp = dithiophosphate, py = pyridine) have been determined by X-ray crystallography. They are isomorphous. The crystal structures are very similar and consist of discrete molecules of [Ni{(iPrO)₂dtp}₂(py)₂] and [Cd{(iPrO)₂dtp}₂(py)₂], respectively. They both crystallize in the monoclinic system, space group P2₁/c, the former with lattice parameters a = 6.489(1) Å, b = 14.830(3) Å, c = 16.386(3) Å, = 99.74(3), and Z = 2; the latter with a = 6.461(3) Å, b = 14.583(4) Å, c = 17.433(4) Å, = 99.55(3)°, and Z = 2. They all display distorted octahedral geometry around the central metal atom. In the complexes, two O,O-diisopropyl dithiophosphate ions act as bidentate ligands with their S atoms coordinated to metal. Each forms a four-membered chelate ring in the equatorial plane. The N atoms from two pyridine ligands are axially coordinated to the metal atom. The Ni–S bond distances are 2.5137(10) and 2.5386(9) Å, and the Ni–N bond distances are 2.127(3) Å. The Cd–S(1) and Cd–S(2) bond distance are 2.694(1) and 2.704(1) Å, respectively, and the Cd–N bond distances are 2.399(3) Å. The IR spectra data is in agreement with the structural data.