Decarbonylation Reaction of [Os3(CO)10(μ-H)(μ-SN2C4H5)]: X-ray Structures of the Two Isomers of [Os3(CO)9(μ-H)(μ 3-η 2-SN2C4H5)]

Abstract  The thermal reaction of [Os₃(CO)₁₀(μ-H)(μ-SN₂C₄H₅)] (1) at 110 °C afforded the new compound [Os₃(CO)₉(μ-H)(μ ₃-η ²-SN₂C₄H₅)] (2) in 84% yield. Compound 2 exists as two isomers, which differ in the disposition of the bridging hydride ligand. Both of the isomers of 2 have been characterized by a combination of elemental analysis, infrared and ¹H NMR spectroscopic data together with single crystal X-ray crystallography. The isomers crystallize together in the triclinic space group P-1 with a = 10.4775(2), b = 13.3056(3), c = 15.0325(3) ?, α = 110.8890(10), β = 99.3880(10), γ = 96.1620(10)°, Z = 2 and V = 1900.31(7) ?³. Index Abstract  The synthesis and the molecular structures of the two isomers of [Os₃(CO)₉(μ-H)(μ ₃-η ²-SN₂C₄H₅)] are described. The isomers differ in the disposition of the hydride ligand.      

Hydrogen Atoms Location in Os<Subscript>3</Subscript>(μ-H)(CO)<Subscript>9</Subscript>(μ<Subscript>3</Subscript>, η<Superscript>2</Superscript>-C<Subscript>2</Subscript>H) from Accurate X-Ray Data at 100 K

Abstract  

The structure of the complex Os₃(μ-H)(CO)₉(μ₃, η²-C₂H) has been determined using X-ray data collected at low temperature (100 K); all hydrogen atoms have been located. The asymmetric unit is formed by two molecules joined through hydrogen bonds involving the hydrogen atoms of C₂H moiety and the oxygen atoms of carbonyl groups. The complex crystallizes in the monoclinic space group P2₁/c with a = 12.94040(2), b = 15.4705(2), c = 16.0164(2) ?, β = 106.0860(10)°, and V = 3,080.85(7) ?³, Z = 8. A molecule is formed by a triangular Os₃ cluster, with metal atoms bearing terminal CO groups. The acetylenic residual is formally π-bonded to two Os atoms in a perpendicular mode and σ-linked to the third Os atom. A bridging hydride atom completes the coordination.     

Reactions of triosmium clusters with indole: X-ray structures of [Os3(CO)10(μ-OH)(μ-OMeCO)] and [Os3(μ-H)(CO)10(μ-1, 2-η2-NC8H6)]

Treatment of [Os₃(CO)₁₂] with indole in presence of a methanolic solution of Me₃NO⋅2H₂O at 60^∘C afforded the previously reported compounds [(μ-H)Os₃(CO)₁₀(μ-OMe)] 2, [(μ-H)Os₃(CO)₁₀(μ-OH)] 3 and [Os₃(CO)₁₀(μ-OH)(μ-OMeCO)] 4 in 10, 5 and 20% yields, respectively. The reaction of [Os₃(CO)₁₀(MeCN)₂] with indole at room temperature gave [(μ-H)Os₃(CO)₁₀(μ-1,2-η²-NC₈H₆)] 5 in 40% yield. Compounds 4 and 5 have been characterized by single crystal X-ray diffraction studies. Compound 4 crystallizes in the monoclinic space group P2(1)/c with a = 23.1239(3), b = 9.8087(4), c = 16.9017(6) ?, β = 92.6998(14)^∘, Z = 8 and V = 3829.3(2) ?³ and 5 crystallizes in the monoclinic space group P2(1)/c with a = 9.009(3), b = 9.764(4), c = 24.906(6) ?, β = 93.452(14)^∘, Z = 4 and V = 2186.9(13) ?³. Compound 4 consists of an open cluster of three osmium atoms with the hydroxy and methoxycarbonyl ligands bridging the open Os–Os edge. Compound 5 consists of an isosceles triangle of osmium atoms with one elongated Os–Os edge which is bridged by the hydride and the indolyl ligands.     

Ligand-induced polyhedral opening in the mixed-metal cluster MeCCo2NiCp(CO)6 by 4,5-Bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd): X-ray structure of Co2NiCp(CO)4[μ2,η2,η1-C(Me)C=C(PPh2)C(O)CH2C(O)](μ2-PPh2)

The mixed-metal cluster MeCCo₂NiCp(CO)₆ (1) reacts with the diphosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) in refluxing CH₂Cl₂ to afford the disubstituted cluster MeCCo₂NiCp(CO)₄(bpcd) (2), which exists as a 1:1 mixture of bridging and chelating bpcd isomers. VT ³¹P NMR spectroscopy confirms that the two bpcd isomers do not interconvert in solution over the temperature range of 182–298 K. Thermolysis of cluster 2 leads to bpcd/cluster activation and formation of the phosphido-bridged cluster Co₂NiCp(CO)₄[μ₂,η²,η¹-C(Me)C=C(PPh₂)C(O)CH₂C(O)](μ₂-PPh₂) (3). The ligand-induced polyhedral expansion that accompanies the formation of the title cluster was established by X-ray diffraction analysis. Co₂NiCp(CO)₄[μ₂,η²,η¹-C(Me)C=C(PPh₂)C(O)CH₂C(O)](μ₂-PPh₂) crystallizes in the triclinic space group P-1, a=9.679(2), b=11.691(2), c=16.653(3) ?, α=85.849(3)°, β=85.456(4)°, γ=66.453(3)°, V=1720.3(6) A³, Z=2, D _cacl=1.632 Mg/m³; R=0.0874, R _w=0.1998 for 7053 observed reflections with I > 2σ(I).     

Spectroscopic and X-ray Diffraction Data on Three Novel Trimetallic Clusters from Thermally Promoted Ligand Substitution in the Tetrahedrane Clusters MeCCo2MoCp(CO)8 and PhCCo2Mo(η5-C5H4CHO)(CO)8

Abstract  

The reaction between the ethylidyne-substituted cluster MeCCo₂MoCp(CO)₈ (1) and the diphosphine ligand 2,3-bis(diphenylphosphino)maleic anhydride (bma) in refluxing CH₂Cl₂ has been investigated and found to afford the new mixed-metal clusters MeCCo₂MoCp(CO)₆[trans-2,3-bis(diphenylphosphino)succinic anhydride] (2) and Co₂MoCp(CO)₅[μ-C(Me)C=C(PPh₂)C(O)OC(O)](μ-PPh₂) (3), with the latter cluster representing the principal reaction product. Refluxing 1 with bma in either 1,2-dichloroethane or toluene yields only 3. The tetrahedrane cluster PhCCo₂Mo(η⁵-C₅H₄CHO)(CO)₈ (4), which contains a formyl-substituted cyclopentadienyl ring, has also been examined with added bma in refluxing CH₂Cl₂ and found to give only Co₂Mo(η⁵-C₅H₄CHO)(CO)₅[μ-C(Ph)C=C(PPh₂)C(O)OC(O)](μ-PPh₂) (5). All three products have been isolated and characterized spectroscopically in solution, and each molecular structure has been determined by X-ray crystallography. Cluster 2 contains a bridging diphosphine ligand with a succinic anhydride ring that results from the formal reduction of the maleic anhydride platform of the bma ligand, while clusters 3 and 5 each exhibit triangular Co₂Mo cores, whose one face is capped by a 6e- C(R)C=C(PPh₂)C(O)OC(O) [where R = Me (3), Ph (5)] ligand. The observed substitution products are discussed as a function of the capping carbyne group, ancillary polyene ligand, and related derivatives prepared by our groups.     

Reactivity of [Re2(CO)8(MeCN)2] With 1-vinylimidazole: X-ray Structures of [Re2(CO)8{η1-NC3H3N(CH=CH2)}2] and [ReCl2(CO)2{η1-NC3H3N(CH=CH2)}2]

Abstract  Treatment of [Re₂(CO)₈(MeCN)₂] with excess 1-vinylimidazole in refluxing benzene gives three new compounds [Re₂(CO)₉{η ¹-NC₃H₃N(CH=CH₂)}] (1), [Re₂(CO)₈{η ¹-NC₃H₃N(CH=CH₂)}₂] (2) and [ReCl₂(CO)₂{η ¹-NC₃H₃N(CH=CH₂)}₂] (3) in 11, 32 and 2% yields, respectively. The solid-state structures of complexes 2 and 3 have been determined by single crystal X-ray diffraction studies. Compound 2 crystallizes in the monoclinic space group C2/c, with lattice parameters a = 13.8378(5) ?, b = 11.8909(5) ?, c = 14.4591(6) ?, β = 116.6470(10)°, Z = 4 and V = 2131.99(15) ?³. Compound 3 crystallizes in the monoclinic space group C2/c, with lattice parameters a = 10.1028(3) ?, b = 13.5640(5) ?, c = 12.5398(4) ?, β = 109.637(2)°, Z = 4 and V = 1618.4(9) ?³. The disubstituted dinuclear compound 2 contains two 1-vinylimidazole ligands coordinated through the imino nitrogen atoms at the equatorial sites, whereas the mononuclear compound 3 contains two carbonyl ligands, two N coordinated η ¹-1-vinylimidazole ligands and two terminal Cl ligands. Graphical Abstract  Two dinuclear complesxes [Re₂(CO)₉{η ¹-NC₃H₃N(CH=CH₂)}] (1) and [Re₂(CO)₈{η ¹-NC₃H₃N(CH=CH₂)}₂] (2) and the mononuclear [ReCl₂(CO)₂{η ¹-NC₃H₃N(CH=CH₂)}₂] (3) were obtained from the reaction of [Re₂(CO)₈(MeCN)₂] with excess 1-vinylimidazole at 80 °C. The X-ray structrures of 2 and 3 are described.      

Dinuclear Ir(III) Complex with an Unusual η<Superscript>1</Superscript>:η<Superscript>3</Superscript>-allylic Bridging Ligand from the Double C–H Activation of 2,5-Dimethylthiophene

Abstract  

The unique dinuclear Ir(III) complex (Cp*IrCl)(μ-H)[μ-(η¹:η³-C₆H₆S)](IrCp*) (1) has been synthesized and characterized by NMR spectroscopy (¹H and ¹³C), elemental analysis, and single crystal X-ray diffraction. It is the first structurally determined complex in which an activated thiophene ligand displays an η³-allylic interaction. 1 appears to form from successive C-H bond activations of 2,5-dimethylthiophene, resulting in its bridging the two iridium centers. The η³-allylic interaction occurs with one of the Ir centers and has Ir–C_thio bond lengths ranging from 2.133(5)-2.207(5) ?; the C–C double bond involved in the interaction has a bond length of 1.438(7) ? compared to 1.348(8) ? for the uncoordinated C–C double bond. The 3-carbon of the thiophene ring bridges both iridium centers with bond lengths of 2.036(5) ? and 2.208(5) ?. 1 crystallizes in space group P−1 with cell constants a = 8.6303(6) ?, b = 9.0153(6) ?, c = 18.1089(12) ?, α = 84.728(1)°, β = 87.534(1)°, γ = 64.373(1)°, and Z = 2. The structure was solved by direct methods and refined to R = 0.0363 (F ² > 2σ(F ²)) and wR = 0.0851 (F ²). The NMR data indicate the solution state structure is consistent with the solid state structure.     

Syntheses and X-ray structures of the bridging and chelating isomers of Os3(CO)10(dmpe)

The substitution chemistry of the activated clusters Os₃(CO)₁₀(MeCN)₂ (1) and Os₃(CO)₁₀(1,5-cod) (2) has been investigated with the bidentate ligand 1,2-bis(dimethylphosphino)ethane (dmpe). Both starting clusters react rapidly with dmpe at room temperature to give the corresponding substitution product Os₃(CO)₁₀(dmpe) (3), whose isomeric composition is shown to depend on the nature of the starting cluster. Whereas the bridged cluster 1,2-Os₃(CO)₁₀(dmpe) (3b) was formed almost exclusively upon reaction with Os₃(CO)₁₀(MeCN)₂, a near statistical mixture of bridging (3b) and chelating (3c) isomers of Os₃(CO)₁₀(dmpe) was found in the reaction employing Os₃(CO)₁₀(1,5-cod). Both dmpe isomers have been characterized in solution by 3iP NMR spectroscopy and their solid-state structures established by X-ray crystallography. The bridged cluster 1,2-Os₃(CO)₁₀(dmpe) crystallizes in the monoclinic space group P2₁/n, a = 9.867(2) Å, b = 17.081(3) Å, c = 14.198(2) Å, β = 95.902(3)°, V = 2380.4(6) ų, Z = 4, and d _calc = 2.793 Mg/m³; R = 0.0435, R _w = 0.0466 for 3519 reflections with I > 2σ(I). The chelated cluster 1,1-Os₃(CO)₁₀(dmpe) crystallizes in the orthorhombic space group C222(1), a = 8.329(3) Å, b = 19.028(6) Å, c = 15.008(5) Å, V = 2379(1) ų, Z = 4, and d _calc = 2.795 Mg/m³; R = 0.0390, R _w = 0.0718 for 2360 reflections with I > 2σ(I).     

Syntheses, Spectroscopic Data, and X-ray Diffraction Structures of the Heterometallic RuRe Face-shared Bioctahedral (η6-cymene)Ru(μ-Cl)3Re(CO)3 and MnRu2 Edge-shared Trioctahedral [fac-ClRu(CO)3]2(μ-Cl)4Mn(H2O)2 Complexes

Abstract  Thermolysis of the diruthenium compound [(η⁶-cymene)RuCl₂]₂ (1) with ClRe(CO)₅ (2) leads to the formation of the new confacial bioctahedral compound (η⁶-cymene)Ru(μ-Cl)₃Re(CO)₃ (3) in good yields; the same product has also been isolated when a mixture of 1 and 2 is irradiated with near UV–vis light for an extended period of time. Heating 1 and ClMn(CO)₅ (4) does not furnish the corresponding manganese analogue of 3 but rather the trioctahedral halide-bridged product [fac-ClRu(CO)₃]₂(μ-Cl)₄Mn(H₂O)₂ (5). 3 and 5 have been fully characterized in solution and their molecular structures established by X-ray crystallography. Graphical Abstract  Thermolysis of [(η⁶-cymene)RuCl₂]₂ (1) with the respective pentacarbonyl ClM(CO)₅ [where M = Re (2); Mn(4)] affords the halide-bridged compounds (η⁶-cymene)Ru(μ-Cl)₃Re(CO)₃ (3) and [fac-ClRu(CO)₃]₂(μ-Cl)₄Mn(H₂O)₂ (5). 3 and 5 have been isolated and characterized spectroscopically in solution and their molecular structures established by X-ray crystallography.      

Neutral Praseodymium(III) Complexes with Tetraselenidoantimonate Ligand: Coligand Influence of Mixed Polyamines on the Coordination Mode of [SbSe4]3? Anion

Abstract  

Mix-coordinated praseodymium(III) complexes concerning the [SbSe₄]³⁻ inorganic ligand, [Pr(en)₂(dien)(η ²-SbSe₄)] (1) and [Pr(en)(trien)(μ-η ¹,η ²-SbSe₄)] _n (2) (en = ethylenediamine, dien = diethylenetriamine, trien = triethylenetetramine), were prepared by solvothermal reactions of Pr₂O₃, Sb and Se in en + dien and en + trien mixed solvents, respectively. They crystallize in the monoclinic space group P2₁/n but with different molecular structures. Crystallographic data for 1: a = 8.610(2), b = 27.722(7), c = 9.294(2) ?, β = 108.987(3)°, V = 2097.7(9) ?³, Z = 4. For 2: a = 14.2987(17), b = 9.0176(9), c = 15.4357(18) ?, β = 100.708(3)°, V = 1955.6(4) ?³, Z = 4. The [SbSe₄]³⁻ anion coordinates to the Pr³⁺ ion in [Pr(en)₂(dien)]³⁺ as a η ²-SbSe₄ chelating ligand, yielding complex 1. It acts as a μ-η ¹,η ²-SbSe₄ bridging ligand to connect the [Pr(en)(trien)]³⁺ ions into the polymer 2. The coordination difference between 1 and 2 is attributed to the coligands of mixed polyamines.     

Synthesis and Structural Characterization of Substituted Salicylate Titanocene Complexes: Three Supramolecular Frameworks Determined by Weak Interactions

Abstract  Based on the reaction between Cp₂TiCl₂ and substituted salicylic acids in the presence of β-cyclodextrin polymer (β-CDP), three four-coordinated titanocene complexes [(η⁵-C₅H₅)₂Ti(S,O′)(OCC₆H₄)·(C₆H₆)_0.5] (1), [(η⁵-C₅H₅)₂Ti{(O,O′)(3,5-Cl₂-OCC₆H₂)}] (2) and [(η⁵-C₅H₅)₂Ti{(O,O′)(3,5-(NO₂)₂-OCC₆H₂)}] (3) were synthesized in high yields and their crystal structures have been determined by single-crystal X-ray diffraction. The structure of 1 has a Monoclinic space group P2₁/c with a = 8.313(3) ?, b = 9.960(4) ?, c = 22.330(8) ?, β = 111.856(11)° and Z = 4. The structure of 2 has a Monoclinic space group P2₁/c with a = 8.0577(13) ?, b = 8.9022(14) ?, c = 21.977(4) ?, β = 96.298(3)° and Z = 4. The structure of 3 has a Triclinic space group P-1 with a = 8.1687(11) ?, b = 8.3027(11) ?, c = 12.7164(17) ?, α = 102.930(2)°, β = 100.479(2)°, γ = 95.458(2)° and Z = 2. Each of the complexes exhibits a three-dimensional framework constructed through weak interactions, which are hydrogen bonding, π–π stacking and C–H···π interactions. It was found that the variation of the substituted salicylate ligands affect the weak interactions as well as the specific framework structure that forms. Graphical Abstract  Three four-coordinated titanocene complexes [(η⁵-C₅H₅)₂Ti(S,O′)(OCC₆H₄)·(C₆H₆)_0.5] (1), [(η⁵-C₅H₅)₂Ti{(O,O′)(3,5-Cl₂-OCC₆H₂)}] (2) and [(η⁵-C₅H₅)₂Ti{(O,O′)(3,5-(NO₂)₂-OCC₆H₂)}] (3) were synthesized in high yields, each of the complexes exhibits a three-dimensional framework constructed through weak interactions. It was found that simple variation of the substituted salicylate ligands affect the weak interactions as well as the specific framework structure that forms. .     

Investigations of 2-Thiazoline-2-thiol as a Ligand: Synthesis and X-ray Structures of [Mn2(CO)7(μ-NS2C3H4)2] and [Mn(CO)3(PPh3)(κ2-NS2C3H4)]

Abstract  Treatment of Mn₂(CO)₁₀ with 2-thiazoline-2-thiol in the presence of Me₃NO at room temperature afforded the dimanganese complexes [Mn₂(CO)₇(μ-NS₂C₃H₄)₂] (1) and [Mn₂(CO)₆(μ-NS₂C₃H₄)₂] (2) in 51 and 34% yields, respectively. Compound 1 was quantitatively converted into 2 when reacted with one equiv of Me₃NO. Reaction of 1 with triphenylphosphine at room temperature furnished the mononuclear complex [Mn(CO)₃(PPh₃)(κ ²-NS₂C₃H₄)] (3) in 66% yield. All three new complexes have been characterized by elemental analyzes and spectroscopic data together with single crystal X-ray diffraction studies for 1 and 3. Compound 1 crystallizes in the orthorhombic space group Pbca with a = 12.4147(2), b = 16.2416(3), c = 19.0841(4) ?, β = 90°, Z = 8 and V = 3848.01(12) ?³ and 3 crystallizes in the monoclinic space group P 2₁/n with a = 10.41730(10), b = 14.7710(2), c = 14.9209(2) ?, β = 91.1760(10)°, Z = 4 and V = 2295.45(5) ?³. Graphical Abstract  Two new dimanganese complexes [Mn₂(CO)₇(μ-NS₂C₃H₄)₂] (1) and [Mn₂(CO)₆(μ-NS₂C₃H₄)₂] (2) were formed when [Mn₂(CO)₁₀] was treated with 2-thiazoline-2-thiol in the presence of Me₃NO. Compound 2 reacts with PPh₃ to give the monomeric complex [Mn(CO)₃(PPh₃ )(κ ²-NS₂C₃H₄)]. The structures of 1 and 3 were established by crystallography. Shishir Ghosh, Faruque Ahmed, Rafique Al-Mamun, Daniel T. Haworth, Sergey V. Lindeman, Tasneem A. Siddiquee, Dennis W. Bennett, Shariff E. Kabir Investigations of 2-thiazoline-2-thiol as a ligand: Synthesis and X-ray structures of [Mn₂(CO)₇(μ-NS₂C₃H₄)₂] and [Mn(CO)₃ (PPh3)(κ ²-NS₂C₃H₄)].      

Synthesis and Crystal Structure of a Bulky β-Diketiminato Ytterbium(II) Iodide Complex

Abstract  

The reaction of YbI₂ with [K(THF)₃(^ButNacnac)] (^ButNacnac = [(DipNCBu^t)₂CH]⁻; Dip = C₆H₃Pr₂ⁱ-2,6) has afforded the dimeric complex, [{Yb(η⁵-^ButNacnac)(THF)(μ-I)}₂] 1. The cell parameters of compound 1 are: P-1, a = 10.498(2), b = 13.146(3), c = 16.293(3); α = 88.06(3), β = 79.43(3), γ = 71.10(3). The compound represents a rare example of a structurally characterized complex exhibiting an η⁵-interaction between a β-diketiminate ligand and an ytterbium(II) center.     

Diphosphine ligand substitution in H4Ru4(CO)12: X-ray diffraction structures and reactivity studies of the cluster compounds H4Ru4(CO)10(P–P) [where P–P–(Z)–Ph2PCH–CHPPh2, bpcd]

The tetraruthenium cluster H₄Ru₄(CO)₁₂ (1) has been studied for its reactivity with the unsaturated diphosphine ligands (Z)–Ph₂PCH–CHPPh₂ and 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) under thermal, near-UV photolysis, and Me₃NO-assisted activation. All three cluster activation methods promote loss of CO and furnish the anticipated substitution products H₄Ru₄(CO)₁₀[(Z)–Ph₂PCH–CHPPh₂] (2) and H₄Ru₄(CO)₁₀(bpcd) (3) that possess a chelating diphosphine ligand. Clusters 2 and 3 have been characterized in solution by IR and NMR spectroscopies, and these data are discussed with respect to the crystallographically determined structure for both new cluster compounds. The ³¹P NMR spectral data and the solid-state structures confirm the presence of a chelating diphosphine ligand in clusters 2 and 3. Cluster 2 crystallizes in the monoclinic space P2₁/c, a=11.768(6) ?, b=18.521(9) ?, c=20.48(1) ?, β=102.291(8)°, V=4361(4) A³, Z=4, and d _calc=1.726 Mg/m³; R=0.0225, R _w=0.0491 for 6798 reflections with I > 2σ(I). The four bridging hydrides were located in H₄Ru₄(CO)₁₀[(Z)–Ph₂PCH–CHPPh₂] and their adopted positions are discussed relative to the solution ¹H NMR spectrum. H₄Ru₄(CO)₁₀(bpcd) crystallizes in the orthorhombic space Pbca, a=19.072(3) ?, b=20.169(3) ?, c=22.774(3) ?, V=8760(2) A³, Z=8, and d _calc=1.870 Mg/m³; R=0.0428, R _w=0.0896 for 10296 reflections with I > 2σ(I). Sealed NMR tubes containing clusters 2 and 3 were found to be exceeding stable towards near-UV light and temperatures up to ca. 125 °C. The surprisingly robust behavior of 2 and 3 is contrasted with the related cluster Ru₃(CO)₁₀(bpcd) that undergoes fragmentation to the donor-acceptor compound Ru₂(CO)₆(bpcd) and the phosphido-bridged compound Ru₂(CO)₆(μ–PPh₂)[μ–C–C(PPh₂)C(O)CH₂C(O)] under mild conditions. The electrochemical properties of each substituted cluster have been investigated by cyclic voltammetry, and our findings are discussed with respect to the reported electrochemical data on the parent cluster H₄Ru₄(CO)₁₂.

Two Novel Three-dimensional Networks Constructed by Mn or Cd Ion and Tartrate: Syntheses,Structures and Properties

Abstract  

Two coordination polymers with the same ligand but different metal ion [Cd(C₄H₄O₆)] _n (1) and [Mn₂(C₄H₄O₆)₂(H₂O)] _n (2) (C₄H₄O₆ = tartrate dianion) have been synthesized. Compound 1 exhibits novel (4, 4)-connected 3-D network with (4.6.8⁴)₄(4.6².8².10)(4.6².8³)(4.6³.8²)₄(4.8⁵)₂ topology, Cd centers are connected by η⁶, μ⁴-mode tartrate ligands. For compound 2, Mn centers are link by η⁶, μ⁴-mode and η⁵, μ³-mode tartrate ligands to form (4, 3)-connected 3-D network with (4.8²)(4.8⁴.10) topology. Additionally, 1 displays an intense luminescent emission and 2 displays weak antiferromagnetic coupling.     

Reinvestigation of the reaction of [Ru3(CO)12] with 2-mercaptobenzothiazole: X-ray structure of [(μ-H)2Ru3 (μ-η2-C7H4NS2)(μ3-η2-C7H4NS2)(CO)7]

Treatment of Ru₃(CO)₁₂ with 2-mercaptobenzothiazole at 68°C gave the known compound [(-H)Ru₃(₃-²-C₇H₄NS₂)(CO)₉] 1 and the new compound [(-H)₂Ru₃(-²-C ₇H₄NS₂) (₃-²-C₇H₄NS₂)(CO)₇] 2 in 15 and 10% yields respectively. Compound 2 has been characterized by elemental analysis, infrared, ¹H NMR and mass spectroscopic data together with single crystal X-ray crystallography. It crystallizes in the monoclinic space group C2/c with a = 31.662(6), b = 14.577(3), c = 11.602(2) Å, = 104.15(3)°, Z = 8, and V = 5192.4(2) ų. The compound consists of a Ru₃ triangle with three different Ru-Ru bond lengths [2.75264, 2.79084, 2.97604 Å] and the two 2-mercaptobenzothiazole ligands are differently attached to the metal atoms. Compound 2 is also obtained by the reaction of 1 with excess 2-mercaptobenzothiazole at 68°C.     

Structures of 355-1355-1355-1tricarbonyl: structural evidence for the near-electroneutrality of the dialkylacetal substituent

The structures of the (benzene dialkylacetal)tricarbonyl chromium complexes [⁶-C₆H₅-CH(OR)₂]Cr(CO)₆ (R=Me,1; Et,2), are reported. The compounds were examined as part of a study of the conformations of the tripodal tricarbonylchromium group. For [⁶-C₆H₅-CH(OMe)₂]Cr(CO)₃,1, monoclinic,P2₁/c (# 14),a=15.235(1) Å,b=6.5304(5) Å,c=12.702 Å, =103.197(1)^o,Z=4. For [⁶-C₆H₅-CH(OEt)₂]Cr(CO)₃,2, monoclinic,P2₁/c (# 14),a=9.859(3) Å,b=10.547(3) Å,c=15.138(3) Å, =108.42(2)^o,Z=4. The data show that the molecules adopt the expected three-legged piano stool structure. The carbonyl ligands in1 adopt an eclipsed arrangement with respect to the arene ring and its substituent, while those in2 are staggered. These conformations are consistent with the notion that the acetal substituent behaves largely as an electroneutral group, or at most as a weak electronic acceptor.     

Structural Studies of Electron Deficient Titanacyclobutanes

Abstract  

Two 16 electron titanacyclobutanes of the formula Ti(C₅H₄R)₂(μ₂-CH₂)₂C(CH₃)(i-C₃H₇) (R=H, CH₃) have been prepared from the reaction of Ti(C₅H₅)₂(μ₂-CH₂)(μ₂-Cl)Al(CH₃)₂ or Ti(C₅H₄CH₃)₂(μ₂-CH₂)(μ₂-Cl)Al(CH₃)₂ with H₂C=C(CH₃)(i-C₃H₇). Structural parameters, most notably lengthened C–C bonds in the titanacyclobutane ring, for both complexes reveal the expected presence of (C–C)→Ti agostic interactions. The complexes are isomorphous, crystallizing in the monoclinic space group Cc. For Ti(C₅H₅)₂(μ₂-CH₂)₂C(CH₃)(i-C₃H₇), a = 11.3459(3) ?, b = 16.2108(4) ?, c = 8.1646(2) ?, β = 105.5276(16)°, V = 1446.87(6)°, D_calc = 1.268 at 150(1) K. For Ti(C₅H₄CH₃)₂(μ₂-CH₂)₂C(CH₃)(i-C₃H₇), a = 12.6591(2) ?, b = 16.2795(4) ?, c = 8.2462(2) ?, β = 107.2421(14)°, V = 1623.04(6) ?³, D_calc = 1.245 at 150(1) K.     

Substituted cyclopentadienyl complexes. 5. Crystal and molecular structure of [(η5-C5H4Me)Fe(CO)(L)I] [L = 2,6-Me2C6H3NC,P(OMe)3, and P(C6H11)3]

The crystal and molecular structures of three derivatives of [( ⁵-C₅H₄Me)Fe(CO)(L)I] [L=2,6-Me₂C₆H₃NC, P(OMe)₃, and P(C₆H₁₁)₃] have been determined. [( ⁵-C₅H₄Me)Fe(CO)(CNC₆H₃Me₂-2,6)I] (1): Space groupP¯1,Z=2,a=13.193(7),b=8.183(5),c=7.465(4) Å,=95.13(5),=94.39(5), =91.09(5)°. [( ⁵-C₅H₄Me)Fe(CO)[P(OMe)₃]I] (2): Space groupP2₁/c,Z=4,a=7.296(3),b=24.471(6),c=8.877(3) Å,=111.92(4)°. [( ⁵-C₅H₄Me)Fe(CO)[P(C₆H₁₁)₃]I] (3): Space groupP2₁/c,Z=4,a=9.809(3),b=14.147(2),c=8.276(3) Å,=103.07(2)°. The structures were refined toR values of 0.045, 0.070, and 0.061, respectively. Disorder was observed in the P(OMe)₃ ligands on2. Structural data for1 and3 reveal (i) a small movement of the Fe atom away from the ringC atom containing the methyl group, (ii) a larger movement of ring C atoms away from the ring least-squares plane for3 than for1, and (iii) a shift toward an allyl-ene bond length variation in the ring distances for3. Molecular mechanics calculations performed on2 produce a low-energy conformation similar to that found in the crystal structure determination of2 with an energy barrier to ring rotation of ±5 kcal mol^–1. A correlation of the structural and molecular mechanics data with the nmr spectra of complexes1 to3 indicates that the steric influence ofL on the ring rotation could be due to ring distortion and/or interaction with the ring methyl group.     

The preparation and crystal structures of [Ru(bpy) (η2-tpy)(CO)CH2OAc]PF6 and [Ru(η3-tpy)(CO)CH2OAc] PF6 (bpy = 2,2′-bipyridine; tpy = 2,2′:6′,2″ terpyridine)

The first titled compound, 1, was obtained by treating [Ru(bpy)(η²-tpy)(CO)CH₂OH]PF₆ with acetic anhydride. Heating 1 in acetonitrile afforded 2, [Ru((η³-tpy)(MeCN)(CO) CH₂OAc]PF₆. Allowing 2 to stand in CH₂Cl₂ followed by concentration and precipitation afforded the second titled compound, 3 ([Ru((η³-tpy)(CO)–CH₂OAc]PF₆), in which the acetoxymethyl group had become bidentate. Crystal data for 1, monoclinic crystal system, space group C2/c, a=26.001(4) ?, b=13.0395(18) ?, c=20.718(3) ?, β=107.700(2)°, V=6691.7(16) ?³, Z=8; for 3, monoclinic crystal system, space group P2₁/n, a=10.864(2) ?, b=16.922(4) ?, c=11.127(2) ?, β=90.907(3)°, V=2045.4(8) ?³, Z=4.