Halfsandwich Carbonylmetal Complexes of Vanadium,Chromium, and Manganese Containing Tri(1‐cyclohepta‐2, 4, 6‐trienyl)phosphane,P(C7H7)3

The photo‐induced substitution of a CO ligand has been used to prepare the halfsandwich complexes (η³‐C₃H₅)V(CO)₄[P(C₇H₇)₃] ( 1 ), (η⁵‐C₅H₅)V(CO)₃[P(C₇H₇)₃] ( 2 ), (η⁷‐C₇H₇)V(CO)₂[P(C₇H₇)₃] ( 3 ), (η⁶‐C₆H₃Me₃)Cr(CO)₂[P(C₇H₇)₃] ( 4 ), and (η⁵‐C₅H₅)Mn(CO)₂[P(C₇H₇)₃] ( 7 ), in which the olefinic phosphane is coordinated as a conventional two‐electron ligand through the lone pair of electrons at phosphorus. Some analogues, which are permethylated at the aromatic ring ( 2* , 4* , 7* ), were included for comparison. Subsequent photo‐elimination of another CO group from 4 or 7 converts the olefinic phosphane into a chelating four‐electron ligand, leading to (η⁶‐C₆H₃Me₃)Cr(CO)[P(C₇H₇)₂(η²‐C₇H₇)] ( 5 ) and (η⁵‐C₅H₅)Mn(CO)[P(C₇H₇)₂(η²‐C₇H₇)] ( 8 ), respectively. The η²‐coordinated double bond in 5 and 8 can be displaced by trimethylphosphite to give (η⁶‐C₆H₃Me₃)Cr(CO)[P(C₇H₇)₃][P(OMe)₃] ( 6 ) and (η⁵‐C₅H₅)Mn(CO)[P(C₇H₇)₃][P(OMe)₃] ( 9 ). The ³¹P and ¹³C NMR spectra of all complexes are discussed, and X‐ray structure analyses for 2 and 8 are presented. Prolonged irradiation of 7 and 8 led to a di(cycloheptatrienyl)phosphido‐bridged dimer, {(η⁵‐C₅H₅)Mn(CO)[P(C₇H₇)₂]}₂( 10 ).     

Synthesis and thermal decomposition of neodymium(III) peroxotitanate to Nd<Subscript>2</Subscript>TiO<Subscript>5</Subscript>

Neodymium(III) peroxotitanate is used as a precursor for obtaining Nd₂TiO₅. The last one possesses numerous valuable electrophysical properties. TiCl₄, Nd(NO₃)₃·6H₂O and H₂O₂ in mol ratio 1:2:10 were used as starting materials. The reaction ambience was alkalized to pH = 9 with a solution of NH₃. The obtained neodymium(III) peroxotitanate and intermediate compounds of the isothermal heating were proved by the help of quantitative analysis and infrared spectroscopy (IRS). It has Nd₄[Ti₂(O₂)₄(OH)₁₂]·7H₂O composition. The absorption band observed in IRS at 831 cm^?1 relates to a triangular bonding of the peroxo group of Ti, at 1062 cm^?1—terminal groups Ti–OH and at 1491 and 1384 cm^?1—the bridging OH^?-groups Ti–O(H)–Ti. Nd₂TiO₅ was obtained by thermal decomposition of neodymium(III) peroxotitanate. The isothermal conditions for decomposition were determined on the base of differential thermal analysis, thermogravimetric and differential scanning calorimetry results in the temperature range of 20–1000 °C. The mechanism of thermal decomposition of Nd₄[Ti₂(O₂)₄(OH)₁₂]·7H₂O to Nd₂TiO₅ was studied. In the temperature range of 20–208 °C, a simultaneous decomposition of the peroxo groups by the separation of oxygen and hydrate water is conducted and Nd₄[Ti₂O₄(OH)₁₂] is obtained. From 208 to 390 °C, the terminal OH^?-groups are separated and Nd₄[Ti₂O₇(OH)₆] is formed. In the range of 390–824 °C, the bridging OH^?-groups are completely decomposed to Nd₂TiO₅. The optimal conditions for obtaining nanocrystalline Nd₂TiO₅ are 900 °C for 6 h and 20–80 nm.     

Synthesis and characterization of complexes η5,η5-(CO)3Mn(C5H4-C5H4)(CO)2Fe-η1,η5-C5H4Mn(CO)3 and μ-(C≡C)[C5H4(CO)2Fe-η1,η5-C5H4Mn(CO)3]2

The complex η⁵,η⁵-(CO)₃Mn(C₅H₄-C₅H₄)(CO)₂Fe-η¹,η⁵-C₅H₄Mn(CO)₃ was synthesized by the reaction of η⁵-Cp(CO)₂Fe-η¹,η⁵-C₅H₄Mn(CO)₃ with BuⁿLi (THF, ?78 °C) and then with anhydrous CuCl₂. The complex μ-(C≡C)[C₅H₄(CO)₂Fe-η¹,η⁵-C₅H₄Mn(CO)₃]₂ was prepared by the reaction of η⁵-IC₅H₄(CO)₂Fe-η¹,η⁵-C₅H₄Mn(CO)₃ with Me₃SnC≡CSnMe₃ (2:1) in the presence of Pd(MeCN)₂Cl₂.     

Heteronukleare Metallatomcluster der Typen X4−n[SnM(CO)4P(C6H5)3]n und M2(CO)8 [μ-Sn(X)M (CO)4P(C6H5)3]2 aus Umsetzungen von SnX2 mit M2(CO)8[P(C6H5)3]2 (X = Halogen; M = Mn,Re; n = 2, 3)

Heteronuclear Metal Atom Clusters of the Types X_4?n[SnM(CO)₄P(C₆H₅)₃]_n and M₂(CO)₈[μ-Sn(X)M(CO)₄P(C₆H₅)₃]₂ by Reaction of SnX₂ with M₂(CO)₈[P(C₆H₅)₃]₂ (X = Halogene; M = Mn, Re; n = 2, 3) The compounds of the both types X_4?n[SnM(CO)₄P(C₆H₅)₃]_n (n = 3; M = Mn; X = F, Cl, Br, I. n = 2: M = Mn, Re; X = Cl, Br, I) and M₂(CO)₈[μ-Sn(X)M(CO)₄P(C₆H₅)₃]₂ (M = Mn; X = Cl, I. M = Re; X = Cl, Br, I) are prepared by reaction of SnX₂ with M₂(CO)₈[P(C₆H₅)₃]₂ (M = Mn, Re). Their IR frequencies are assigned. In Re₂(CO)₈[μ-Sn(Cl)Re(CO)₄P(C₆H₅)₃]₂ the central molecule fragment contains a planar Re₂Sn₂ rhombus with a transannular Re? Re bond of 316.0(2) pm. Each of the Sn^IV atoms is connected with the terminal ligands Cl and Re(CO)₄P(C₆H₅)₃. These ligands are in transposition with respect to the Re₂Sn₂ ring. The mean values for the remaining bond distances (pm) are: Sn? Re = 274.0(3); Sn? Cl = 243(1), Re? C = 176(5), Re? P = 242.4(9), C? O = 123(5). The factors with an influence on the geometrical shape of such M₂Sn₂ rings (M = transition metal) are discussed.     

Preparation of new (η5-C5H4CH3)Mn(NO)(PPh3) and (η7-C7H7)Mo(CO)-(PPh3) complexes

The complex (η⁵-C₅H₄CH₃)Mn(NO)(PPh₃)I has been prepared by the reaction of NaI with [(η⁵-C₅H₄CH₃)Mn(NO)(CO)(PPh₃)]⁺ and also by the reaction of [(η⁵-C₅H₄CH₃)Mn(NO)(CO)₂]⁺ with NaI followed by PPh₃. This iodide compound reacts with NaCN to yield (η⁵-C₅H₄CH₃)Mn(NO)(PPh₃)CN which is ethylated by [(C₂H₅)₃O]BF₄ to yield [(η⁵-C₅H₄CH₃)Mn(NO)(PPh₃)(CNC₂H₅)]⁺. Both [(η⁵-C₅H₄CH₃)Mn(NO)(CO)₂]⁺ and [(η⁵-C₅H₄CH₃)Mn(NO)(PPh₃)(CO)]⁺ react with NaCN to yield [(η⁵-C₅H₄CH₃)Mn(NO)(CN)₂]^?. This anion reacts with Ph₃SnCl to yield cis-(η⁵-C₅H₄CH₃)Mn(NO)(CN)₂SnPh₃ and with [(C₂-H₅)₃O]BF₄ to yield [(η⁵-C₅H₄CH₃)Mn(NO)(CNC₂H₅)₂]⁺. The reaction of (η⁵-C₅-H₄CH₃)Mn(NO)(PPh₃)I with AgBF₄ in acetonitrile yields [(η⁵-C₅H₄CH₃)Mn-(NO)(PPh₃)(NCCH₃)]⁺. The complex (η⁵-C₅H₄CH₃)Mn(NO)(CO)I, produced in the reaction of [(η⁵-C₅H₄CH₃)Mn(NO)(CO)₂]⁺ with NaI, is not stable and decomposes to the dimeric complex (η⁵-C₅H₄CH₃)₂Mn₂(NO)₃I for which a reasonable structure is proposed. Similar dimers can be prepared from the other halide salts. The reaction of (η⁷-C₇H₇)Mo(CO)(PPh₃)I with NaCN yields (η⁷-C₇-H₇)Mo(CO)(PPh₃)CN which is ethylated by [(C₂H₅)₃O]BF₄ to yield [(η⁷-C₇H₇)-Mo(CO)(PPh₃)(CNC₂H₅)]⁺. The interaction of this molybdenum halide complex with AgBF₄ in acetonitrile and pyridine yields [(η⁷-C₇H₇)Mo(CO)(PPh₃)-(NCCH₃)]⁺ and [(η⁷-C₇H₇)Mo(CO)(PPh₃)(NC₅H₅)]⁺, respectively. Both (η⁵-C₅-H₄CH₃)Mn(NO)(PPh₃)I and (η⁷-C₇H₇)Mo(CO)(PPh₃)I are oxidized by NOPF₆ to the respective 17-electron cations in acetonitrile at ?78°C but revert to the neutral halide complex at room temperature. This result is supported by electrochemical data.     

The Reactions of Two New Alkoxy-silyl Functionalized Alkynes with M<Subscript>3</Subscript>(CO)<Subscript>12</Subscript> {M = Fe,Ru} and Co<Subscript>2</Subscript>(CO)<Subscript>8</Subscript>. Spectroscopic Identification of the Products

The new alkoxysilyl-functionalized alkynes [HC≡CCH₂N(H)C(=O)N(H)(CH₂)₃Si(OEt)₃] and [HC≡C(C₆H₄)–N(H)C(=O)N(H)(CH₂)₃Si(OEt)₃] have been synthesized using literature methods. These have been reacted with Fe₃(CO)₁₂, Ru₃(CO)₁₂ and Co₂(CO)₈. With the iron carbonyl only decomposition was observed: with Ru₃(CO)₁₂ splitting of the alkynes into their parent components and formation of the complexes (μ-H)Ru₃(CO)₉[HC=N(CH₂)₃Si(OEt)₃], (μ-H)Ru₃(CO)₉[C–C(C₆H₄)NH₂] and (μ-H)₂Ru₃(CO)₉[HC–CCH₃] occurred. Finally, with Co₂(CO)₈ formation of complexes Co₂(CO)₆(HC₂R) R=(C₆H₄)NH₂, CH₂NH(CO)NH(CH₂)₃Si(OEt)₃, (C₆H₄)NH(CO)NH(CH₂)₃Si(OEt)₃ containing the intact alkynes could be obtained.     

Oxidative Addition of Diphenyl Disulfide/Thiophenol to [Mn(CO)5]−: Crystal Structure of cis-[Mn(CO)4(SPh)2]−

Oxidative addition of diphenyl disulfide to the coordinatively unsaturated [Mn(CO)₅]^? led to the formation of low-spin, six-coordinate cis-[Mn(CO)₄(SPh)₂]^?. The complex cis-[PPN][Mn(CO)₄(SPh)₂] crystallized in monoclinic space group P2₁/c with a = 9.965(2) Å, b = 24.604(5) Å, c = 19.291(4) Å, β = 100.05(2)°, V = 4657(2)ų, and Z = 4; final R = 0.036 and R_w = 0.039. Thermal transformation of cis-[Mn(CO)₄(SPh)₂]^? to [(CO)₃Mn(μ-SPh)₃Mn(CO)₃]^? was completed overnight in THF at room temperature. Additionally, reaction of [Mn(CO)₅]^? and PhSH in 1:2 mole ratio also led to cis-[PPN](Mn(CO)₄(SPh)₂]. Presumably, oxidative addition of PhSH to [Mn(CO)₄]^? was followed by a Lewis acid-base reaction to form cis-[Mn(CO)₄(SPh)₂]^? with evolution of H₂.     

Cuboidal oxalate cluster complexes with the Mo<Subscript>3</Subscript>CuQ<Subscript>4</Subscript><Superscript>5+</Superscript> cluster core (Q = S or Se): synthesis,structure, and electrochemical properties

The reactions of the [Mo₃(μ₃-Q)(μ₂-Q)₃(H₂O)₃(C₂O₄)₃]²⁻ complex (Q = S or Se) with CuX salts (X = Cl, Br, I, or SCN) in water produce the cuboidal heterometallic clusters [Mo₃(CuX)(μ₃-Q)₄(H₂O)₃(C₂O₄)₃]²⁻, which were isolated as the potassium and tetraphenylphosphonium salts. Two new compounds, K₂[Mo₃(CuI)(μ₃-S)₄(H₂O)₃(C₂O₄)₃]·6H₂O and (PPh₄)₂[Mo₃(CuBr)(μ₃-S)₄(H₂O)₃(C₂O₄)₃]·7H₂O, were structurally characterized. All compounds were characterized by elemental analysis and IR spectroscopy. The K₂[Mo₃(CuI)(μ₃-Se)₄(H₂O)₃(C₂O₄)₃] compound was characterized by the ⁷⁷Se NMR spectrum; the (PPh₄)₂[Mo₃(CuI)(μ₃-S)₄(H₂O)₃(C₂O₄)₃], (PPh₄)₂[Mo₃(CuI)(μ₃-Se)₄(H₂O)₃(C₂O₄)₃] and K₂[Mo₃(CuSCN)(μ₃-S)₄(H₂O)₃(C₂O₄)₃]·7H₂O compounds, by electrospray mass spectra. Dedicated to Academician G. A. Abakumov on the occasion of his 70th birthday. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1639–1644, September, 2007.     

Capping [H<Subscript>8−n</Subscript>Ni<Subscript>42</Subscript>C<Subscript>8</Subscript>(CO)<Subscript>44</Subscript>]<Superscript>n−</Superscript> (n = 6, 7, 8) Octa-carbide Carbonyl Nanoclusters with [Ni(CO)] and [CuCl] Fragments

The reactions of [Ni₁₆(C₂)₂(CO)₂₃]^4? and [Ni₃₈C₆(CO)₄₂]^6? with CuCl afforded mixtures of the previously reported [HNi₄₂C₈(CO)₄₄(CuCl)]^7? bimetallic octa-carbide cluster and the new [HNi₄₃C₈(CO)₄₅]^7? and [HNi₄₄C₈(CO)₄₆]^7? homo-metallic octa-carbides. The three species have very similar properties resulting always in co-crystals such as [NMe₄]₇[HNi_42+2xC₈(CO)_44+2x(CuCl)_1?x]·6.5MeCN (x = 0.14) (86% [HNi₄₂C₈(CO)₄₄(CuCl)]^7?, 14%[HNi₄₃C₈(CO)₄₅]^7?/[HNi₄₄C₈(CO)₄₆]^7?) and [NMe₄]₇[HNi_42+2xC₈(CO)_44+2x(CuCl)_1?x]·5.5MeCN (x = 0.30) (70% [HNi₄₂C₈(CO)₄₄(CuCl)]^7?, 30% [HNi₄₃C₈(CO)₄₅]^7?/[HNi₄₄C₈(CO)₄₆]^7?). The new homo-metallic octa-carbides can be obtained free from the Ni–Cu octa-carbido cluster by reacting [Ni₁₀(C₂)(CO)₁₆]^2? in thf with a stoichiometric amount of CuCl, and crystals of [NMe₄]₆[H₂Ni_43+xC₈(CO)_45+x]·6MeCN (x = 0.72), which contain [H₂Ni₄₄C₈(CO)₄₆]^6? (72%) and [H₂Ni₄₃C₈(CO)₄₅]^6? (28%), have been obtained. Despite the different charges and compositions, these anions display almost identical structures, which are also closely related to those previously reported for the bimetallic Ni–Cd octa-carbido clusters [Ni_42+xC₈(CO)_44+x(CdCl)]^7? and [HNi_42+xC₈(CO)_44+x(CdBr)]^6?. Indeed, all these clusters are based on the same Ni₄₂C₈ cage decorated by miscellaneous [CdX]⁺ (X = Cl, Br), [CuCl] and [Ni(CO)] fragments.     

Reactivity of triangular oxalate cluster complexes [M<Subscript>3</Subscript>Q<Subscript>7</Subscript>(C<Subscript>2</Subscript>O<Subscript>4</Subscript>)<Subscript>3</Subscript>]<Superscript>2−</Superscript> (M = Mo or W; Q = S or Se)

The reactions of the oxalate complexes [M₃Q₇(C₂O₄)₃]²⁻ (M = Mo or W; Q = S or Se) with Mn^II, Co^II, Ni^II, and Cu^II aqua and ethylenediamine complexes in aqueous and aqueous ethanolic solutions were studied. The previously unknown heterometallic complexes [Mo₃Se₇(C₂O₄)₃Ni(H₂O)₅]·3.5H₂O (1) and K₃{[Cu(en)₂H₂O]([Mo₃S₇(ox)₃]₂Br)}·5.5H₂O (2) were synthesized. In these complexes, the oxalate clusters serve as monodentate ligands. The K(H₂en)₂[W₃S₇(C₂O₄)₃]₂Br·4H₂O salt (3) was isolated from solutions containing Co^II, Ni^II, or Cu^II aqua complexes and ethylenediamine. The reaction of [Mo₃Se₇(C₂O₄)₃]²⁻ with HBr produced the bromide complex [Mo₃Se₇Br₆]²⁻, which was isolated as (Bu₄N)₂[Mo₃Se₇Br₆] (4). Complexes 1–3 were characterized by X-ray diffraction, IR spectra, and elemental analysis. The formation of 4 was detected by electrospray mass spectrometry. Dedicated to Academician G. A. Abakumov on the occasion of his 70th birthday. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1645–1649, September, 2007.     

Structure of an Unordinary 1-D Cobalt(II) Polymer Formed upon the Dissolution of the Mononuclear Co(OOPh)<Subscript>2</Subscript>[O(H)Me]<Subscript>4</Subscript> Adduct in Chloroform

The structure of the 1-D {[Co₂(μ,η²-OOCPh)(μ-OOCPh)₂(O(H)Me)₂](μ-OOCPh)(HCCl₃)} _n polymer formed upon the dissolution of single crystals of the mononuclear Co(OOPh)₂[O(H)Me]₄ adduct containing coordinated labile methanol molecules in boiling chloroform was studied by X-ray diffraction.     

Syntheses and Characterization of Manganese-Tellurolate Complexes by Using Chelating Metalloligand cis-[Mn(Co)4(TePh)2]− and Potential Electrophilic TeMe+ Reagent

The cis-[Mn(CO)₄(TePh)₂]^?, similar to bidentate ligand PhTe(CH₂)₃TePh, acts as a “chelating metalloligand” for the synthesis of metallic tellurolate compounds. The reaction of cis[Mn(CO)₄(TePh)₂]^? with BrMn(CO)₅ in THF leads to a mixture of products[(CO)₃,BrMn(μ-TePh)₂Mn(CO)₄]^? (1) and Mn₂(μ-TePh)₂(CO)_g (2). Complex 1 crystallizes in the triclinic space group Pl? with a = 11.309(3) Å, b = 14.780(5) Å, c = 19.212(6) Å, a = 76.05(3)° β = 72.31(3)°, γ = 70.41(3)° V = 2848(2) Å₃, Z = 2. Final R = 0.034 and R_w = 0.035 resulting from refinement of 10021 total reflections with 677 parameters, Dropwise addition of (MeTe)₂ to a solution of [Me₃O][BF₄] in CH₃CN leads to formation of [Me₂TeTeMe][BF₄], a potential MeTe⁺ donor ligand. In contrast to oxidative addition of diphenyl ditelluride to [Mn(CO)s]^? to give cis-[Mn(CO)₄(TePh)₂]^? which was thermally transformed into [(CO)₃Mn(μ-TePh)₃Mn(CO)₃]^?, reaction of [Mn(CO)₅]^?with [Me₂TeTeMe]⁺ proceeded to give the monomeric species MeTeMn(CO)₅ as initial product which was then dimerized into Mn₂(μ-TeMe)₂(CO)_g (4).     

Isolation of New Disilanylene-bridged Bis（cyclopentadienyl）tetracarbonyldiiron Complexes and Molecular Structure of [η^5, η^5-C5H4SiMe（SiMePh2）C5H4]Fe2（CO）2（μ-CO）2

1,2-Diphenyl-1,2-dimethyldisilanylene-bridged bis-cyclopentadienyl complex[η~5,η~5-C_5H_4PhMeSiSiMePh-C_5H_4]Fe_2(CO)_2(μ-CO)_2(1)was synthesized by a modified procedure,from which the trans-isomer 1b that was pre-viously difficult to obtain has been isolated for the first time.More interestingly,two new regio-isomers[η~5,η~5C_5H_4SiMe(SiMePh_2)C_5H_4]Fe_2(CO)_2(μ-CO)_2(2)and [η~5,η~5-C_5H_4Me_2SiSiPh_2C_5H_4]Fe_2(CO)_2(μ-CO)_2(3)were occa-sionally obtained during above process,the novel structures of which opened up new options for further study ofthis type of Si—Si bond-containing transition metal complexes.The molecular structure of 2 has been determinedby the X-ray diffraction method.     

Synthese und dynamisches Verhalten von [Rh2(μ-H)3H2(PiPr3)4]+. Beiträge zur Reaktivität des Tetrahydridodirhodium-Komplexes [Rh2H4(PiPr3)4]

Synthesis and Dynamic Behaviour of [Rh₂(μ-H)₃H₂(PiPr₃)₄]⁺. Contributions to the Reactivity of the Tetrahydridodirhodium Complex [Rh₂H₄(PiPr₃)₄] An improved synthesis of [Rh₂H₄(PiPr₃)₄] ( 2 ) from [Rh(η³-C₃H₅)(PiPr₃)₂] ( 1 ) or [Rh(η³-CH₂C₆H₅)(PiPr₃)₂] ( 3 ) and H₂ is described. Compound 2 reacts with CO or CH₃OH to give trans-[RhH(CO)(PiPr₃)₂] ( 4 ) and with ethene/acetone to yield a mixture of 4 and trans-[RhCH₃(CO)(PiPr₃)₂] ( 5 ). The carbonyl(methyl) complex 5 has also been prepared from trans-[RhCl(CO)(PiPr₃)₂] ( 6 ) and CH₃MgI. Whereas the reaction of 2 with two parts of CF₃CO₂H leads to [RhH₂(η²-O₂CCF₃) · (PiPr₃)₂] ( 8 ), treatment of 2 with one equivalent of CF₃CO₂H in presence of NH₄PF₆ gives the dinuclear compound [Rh₂H₅(PiPr₃)₄]PF₆ ( 9a ). The reactions of 2 with HBF₄ and [NO]BF₄ afford the complexes [Rh₂H₅(PiPr₃)₄]BF₄ ( 9b ) and trans-[RhF(NO)(PiPr₃)₂]BF₄ ( 11 ), respectively. In solution, the cation [Rh₂(μ-H)₃H₂(PiPr₃)₄]⁺ of the compounds 9a and 9b undergoes an intramolecular rearrangement in which the bridging hydrido and the phosphane ligands are involved.     

Gradual transformation of Ca(OH)<Subscript>2</Subscript> into CaCO<Subscript>3</Subscript> on cement hydration

The low temperature of decomposition of some calcium carbonates and the bending of the TG curves of hydrated cement between 500 and 800°C suggested the presence of some complex compound(s), which needed complementary investigation (XRD, TG). Stepwise transformation of portlandite (and/or lime) into calcium carbonate, with intermediate steps of calcium carbonate hydroxide hydrates (CCH-1 to CCH-5), was indicated by the previous study of two OPC. This was checked here on four cements ground for t _g=15, 20, 25 and 30 min and hydrated either in water vapour, successively at RH=1.0, 0.95 and 0.5 for 2 weeks each (WR1, WR2 and WR3, respectively) or as mortars in liquid water (1m), followed by WR as above. The d[001] spacing of portlandite was confirmed to vary: here between the lowest and the highest standard values. The diffractograms of n=32 different samples were analyzed for presence of standard CCH peaks, generally slightly displaced. These were: CCH-1 [Ca₃(CO₃)₂(OH)₂]: N=11 peaks, of three different d[hkl] spacings, CCH-2 [Ca₆(CO_2.65)₂(OH₆₅₇)₇(H₂O)₂]: N=10 for two d[hkl], CCH-3 [Ca₃(CO₃)₂(OH)₂·1.5H₂O]: N=14 for five d[hkl], CCH-4, ikaite [CaCO₃(H₂O)₆]: N=13 for six d[hkl], CCH-5[CaCO₃(H₂O)]: N=15 for five d[hkl]. Thus the most probable is the presence of the last three. The stepwise transformation of Ca(OH)₂ into CaCO₃ was confirmed:     

The reaction of [H4Ru4(CO)12] with 1-penten-3-yne: dimerization and trimerization through the triple bonds

The clusters [Ru₄(μ-CO)(CO)₁₀(μ₄-η¹:η²:η¹:η²-C₅H₆)₂] (1), [Ru₄(CO)₈(μ₄-η⁴:η¹:η¹:η¹:η³-C₁₀H₁₂)(μ₃-η³:η²:η¹-C₅H₆)] (2) and [Ru₄(CO)₁₀(μ₄-η⁴:η¹:η¹:η³:η¹-C₁₅H₁₆)] (3) have been prepared from the reaction of [H₄Ru₄(CO)₁₂] with 1-penten-3-yne. This reaction is observed to proceed with dimerization and trimerization through the triple bonds. The products were characterized spectroscopically by ¹H- and ¹³C-NMR. X-ray crystal structures of compounds 1 and 2 are also described.     

Solvent induced ionisation of η-allydicarbonylmolybdenum(II) complexes

[MoCl(η-C₃H₅)(CO)₂(MeCN)₂] dissolved in aprotic solvents is extensively ionised to [Mo(η-C₃H₅)(CO)₂(MeCN)₃]⁺[Mo₂Cl₃(η-C₃H₅)₂(CO)₄]^- with the liberation of free acetonitrile. The corresponding bromo- complex shows similar but less pronounced ionisation in (CD₃)₂CO, whereas the iodo-complex retains its molecular structure.     

Crystal Structure Of [Au(Dien)Cl]<Subscript>2</Subscript>[Re<Subscript>4</Subscript>Te<Subscript>4</Subscript>(Cn)<Subscript>12</Subscript>]Sd5H<Subscript>2</Subscript>O

The structure of the [Au(Dien)Cl]₂[Re₄Te₄(CN)₁₂]·5H₂O compound prepared in an aqueous medium by the reaction of a gold(III) complex [Au(Dien)Cl]Cl₂ with a tetranuclear tetrahedral tellurocyanide cluster complex of rhenium K₄[Re₄Te₄(CN)₁₂]·5H₂O is determined by single crystal X-ray diffraction.     

Röntgenstrukturanalyse eines Carben-Additionsproduktes an Dicarbonyl-η5-methylcyclopentadienyl-Tetrahydrofuranmangan, μ-Cyclobuta[1, 2-a:3, 4-a′] dicyclopenten-bis[dicarbonyl-η5-methylcyclopentadienylmangan], [(η5-C5H4CH3)Mn (CO)2]2(μ2-C10H8)

X-Ray Structure Analysis of a Carbene Addition Product to Dicarbonyl-η⁵-methylcyclopentadienyltetrahydrofuranmanganese, μ-Cyclobuta[1, 2-a:3, 4-a′] dicyclopentene-bis-(dicarbonyl-η⁵-methylcyclopentadienylmanganese),[( η⁵-C₅H₄CH3)Mn(CO) ₂]₂(μ₂-C₁₀H₈) The crystal and molecular structure of the title compound has been determined by means of X-ray structure analysis. The species is the first example of an oligocyclic dicarbene stabilized by complex formation.