Search

The synthesis of [Au{S=C(NH2)2}2][SO3Me] (1) (a) by the anodic oxidation of gold metal in an anolyte of thiourea and methansulfonic acid and (b) by the reaction of Au(OH)3 with an aqueous solution of methanesulfonic acid in the presence of thiourea is reported. The structure of 1 in the solid state has been determined by single-crystal X-ray diffraction showing a linear S–Au–S unit with the thiourea ligands in a leaflet structure folded by 113.2(3)°. The cation of complex 1 is a dimer, based on short S · · · C interactions between two adjacent mononuclear cations. The thermal decomposition behavior of 1 was studied by TG and TG-MS confirming that it decomposes under inert gas or oxygen atmosphere in four steps in the temperature range of 200–650°C. Initial decomposition starts with the release and fragmentation of one of the thiourea ligands, followed by the anion degradation. Powder X-ray diffraction studies specified the formation of gold metal. Based on this observation, complex 1 was used as precursor for the formation of gold nanoparticles (Au NPs) in 1-hexadecylamine (c = 4.0 mol L−1) at T = 330°C without any addition of reducing agents. TEM, electron diffraction, and UV/Vis spectroscopy studies were carried out. Au NPs of size 15 ± 4 nm were formed, showing the characteristic surface plasmon resonance at 528 nm.

The ¦-ketoiminato complex [Pd(OAc)L] (3) can be synthesized by the reaction of bis(benzoylacetone)diethylenetriamine (1, = LH) with [Pd(OAc)2] (2). The structure of 3 in the solid state has been determined by single X-ray diffraction analysis. Complex 3 crystallizes as a dimer (3 2), which is formed by hydrogen bonds between NH and OOAc functionalities of two adjacent ligands. Each of the Pd atoms is complexed by one ON2 donor unit of the polydentate ligand L − and an acetate group. Pd–Pd interactions and hydrogen bond formation between a NH and the C=O acetate moiety lead to a [4 + 2] coordination at Pd. The non-coordinated part of L exists in its ¦-keto-enamine form. The thermal decomposition behavior of 3 2 was studied by TG (thermogravimetry) and TG-MS showing that 3 2 decomposes between 200 and 500°C independent of the applied atmosphere. Under oxygen PdO is produced, while under argon Pd is formed as confirmed by PXRD measurements. Complex 3 2 was applied as a spin-coating precursor (conc. 0.1 mol L−1, volume 1.5 mL, 3000 rpm, deposition time 6 min, heating rate 50 K min−1, holding time 60 min (Ar) and 120 min (air) at T = 800°C). The as-obtained samples are characterized by granulated particles of Pd/PdO on the substrate surface. EDX (energy-dispersive X-ray spectroscopy) and XPS (X-ray photoelectron spectroscopy) measurements confirmed the formation of Pd (Ar) or PdO (O2) with up to 12 mol% C impurity.

The synthesis of the tri-coordinated ferrocenecarbonitrile silver(I) complex [Ag(N≡CFc)3]OTf (3) is reported. Its electrochemical behavior shows that the three ferrocenyl units are oxidized in a very close potential range. In addition, the molecular structure of3in the solid state is discussed, showing that silver(I) is exclusively coordinated by three ferrocenecarbonitrile molecules.

A detailed synthetic procedure based on the use of urea, dichlorophthalic acid, respective transition metal halides and [NH4]2[MoO4] as a catalyst in the melt or by using 1,2,4-trichlorobenzene as a high-boiling inert solvent is described to gain 2,3,9,10,16,17,23,24-metallooctachlorophthalocyanines (MPcCl8 compounds with M=Mn, Fe, Co, Ni, Cu). In cases that a first purification by subsequent treatment of the crude materials with HCl, NaOH and HCl would not give rise to analytically pure compounds, a second novel purification by using pyridine is described. The degree of purity, exceeding always 98%, is determined by thermogravimetric analysis. Comparative IR, UV/Vis and PXRD studies of the MPcCl8 compounds are reported.

A zinc(II) complex of cis-1,2-diaminocyclohexane (Dach), [Zn(Dach)2][ZnCl4] (1), was prepared and its structure was determined by X-ray crystallography. Theoretical (density functional theory) studies were performed for the two model compounds, [Zn(Dach)2][ZnCl4] (1) and {[Zn(Dach)2][ZnCl4]}3 (1 3 ). The structure of complex 1 is composed of [Zn(Dach)2]2+ cations and [ZnCl4]2− anions. The Zn1 atom in the cationic complex adopts a severely distorted tetrahedral geometry, while in the anionic part, Zn2 displays only a slight distortion from tetrahedral coordination. The adjacent cations and anions are associated with each other through hydrogen bonding interactions to form a two-dimensional network in the solid state.

A copper(II) polymeric complex {[Cu(phen)2(CN)][Ag(CN)2] · 3H2O} n , 1 (phen = 1,10-phenanthroline), has been prepared and structurally characterized. The compound crystallizes in the monoclinic space group P21/c with [Cu(phen)2(CN)]+ and [Ag(CN)2]− units and three water molecules. The cationic and anionic units are linked to each other through M-π and π–π interactions. The array is extended further by hydrogen bonding and π–π interactions to form a 3D network.

A cyanido-bridged Zn(II)-Ag(I) bimetallic coordination polymer, {[Zn(phen)2(H2O){Ag(CN)2}] [Ag(CN)2]·MeOH}n (1), was prepared using ZnCl2, 1,10-phenanthroline (phen) and K[Ag(CN)2] and characterized by IR spectroscopy, thermal analysis and X-ray crystallography. The crystal structure of 1 consists of dinuclear [Zn(phen)2(H2O){Ag(CN)2}]+ cations, [Ag(CN)2]- anions and a methanol molecule. The non-coordinated [Ag(CN)2]- anions are linked to the [Zn(phen)2(H2O){Ag(CN)2}]+ complex cations through argentophilic interactions leading to the formation of chains. The chains are connected by hydrogen bonds and π-π interactions to give a 3D network.

Me3Si-substituted indenes of type 1-SiMe3-3,4-(CH2)3C9H5 (9), 1-SiMe3-4-R-7-R′C9H5 (11a, R = R′ = Me; 11b, R = R′ = Ph; 11c, R = Me, R′′ = Ph) and 1,1′ -(SiMe3)2-4,7-Me2C9H4 (12) were synthesised as precursors for piano-stool type halfsandwich indenyl-titanium trichloride complexes.Treatment of 9, 11, and 12 with equimolar amounts of TiCl4 gives the complexes (η5-3,4-(CH2)3C9H5)TiCl3 (13), (η5-4-R-7-R′C9H5)TiCl3 (14a, R =R′ = Me; 14b, R =R′= Ph; 14c, R = Me, R′ = Ph), and (η5-1-SiMe3-4,7-Me2C9H4)TiCl3 (15), respectively, with liberation of Me3SiCl.Detailed UV/vis spectroscopic and cyclic voltammetric studies were carried out which allow a comparison of substituent effects in 13 - 15.

A star-shaped oligobenzoate with short peripheral propyloxy chains (1) forms single crystals 1· (Me2CO)0.5 with a triclinic unit cell from acetone. The oligobenzoate arms are fully extended, possessing only carboxy groups with s-trans conformation. Aliphatic chains and oligobenzoate scaffold do not nano-segregate as proposed for other derivatives which assemble in liquid crystalline phases, but instead, the polar arms occupy the voids between arms of neighboring stars. Although a model based on this scenario may rationalize the small column diameter in the LC phase of longchain derivatives, the low density of the resulting material points rather to the recently established representation with folded conformers self-assembling in columns by nano-segregation.

The synthesis of the heterobimetallic hafnium(IV)-nickel(0) complexes {[Hf](μ-σ ,π- C≡CR)2}Ni(CO) (3a, [Hf] = (η5-C5H5)2Hf, R = Ph; 3b, [Hf] = (η5-C5H4SiMe3)2Hf, R = tBu) in which an early (Hf) and a late (Ni) transition metal atom are bridged by σ - and π-bound alkynyl groups succeeds by treatment of [Hf](C≡CR)2 (1a, [Hf] = (η5-C5H5)2Hf, R = Ph; 1b, [Hf] = (η5-C5H4SiMe3)2Hf, R = tBu) with equimolar amounts of Ni(CO)4 (2). The reaction chemistry of 1and 3towards different substrates is discussed. Treatment of 3bwith P(OMe)3 (4a) affords the mononuclear nickel monocarbonyl complex Ni(CO)[P(OMe)3]3 (5), while the reaction of 1aor 1bwith MCl2 (6a, M = Fe; 6b, M = Ni; 6c, M = Co) produces by an cyclopentadienyl transfer from hafnium to M the sandwich compounds (η5-C5H4R’)2M (M = Fe: 7a, R’ = H; 7b, R’ = SiMe3; M = Ni: 7c, R’ = H; 7d, R’ = SiMe3; M = Co: 7e, R’ = H). Addition of KOH to 1b or 3b, respectively, affords the homobimetallic hafnium complex {[Hf](C≡CR)}2O (8) in which two [Hf](C≡CR) fragments are bridged by an oxygen atom. Possible reaction mechanisms for the formation of 5, 7and 8by starting from 1or 3will be given. The result of the X-ray structure analysis of 8is reported. Complex 8crystallises in the monoclinic space group C2/c with the cell parameters a = 24.437(8), b = 14.655(5), c = 14.123(4) Å, β = 101.67(2)◦, V = 4953(3) Å3, Z = 4 and D = 1.454 g cm−3. Complex 8contains a linear Hf-O-Hf unit with pseudo-tetrahedral coordinated hafnium atoms.

Dinuclear nickel(II) and palladium(II) complexes with Schiff-base ligands (derived form salicylaldehyde condensed with 2-amino-1-alcohols or from 2-hydroxy-5-methylisophthaldialdehyde and pyridine-2-carboxaldehyde condensed with semicarbazide, thiosemicarbazide, carbonodihydrazide, or thiocarbonodihydrazide) can be activated with the co-catalysts methylalumoxane (MAO) or tris(pentafluorophenyl)borane/triethylaluminium, B(C6F5)3/AlEt3 for the vinyl/addition polymerization of norbornene to reach activities of up to 2.4 · 107 gpolymer/mol(metal)·h (molar ratios metal:AlMAO = 1:100, metal:borane:AlEt3 = 1:9:10). Polymer characterization by GPC gave molar mass distributions of Mw/Mn ≈ 2, thereby indicating a coordination polymerization with a single-site character of the active species.

The preparation of the first and second generation carbosiloxane dendrimers Si[OCH2- CH2CH2 SiMe(OCH2C=CH)2]4 (3) and Si{OCH2H2CH2SiMe[OCH2CH2CH2SiMe(OCH2 - C=CH)2]2}4 (5) by the reaction o f Si(OCH2CH2CH2SiMeCl2)4 (1) or Si[OCH2CH2CH2SiMe- (OCH2CH2CH2SiMeCl2)2]4 (4) with HOCH2C =CH (2) in the presence o f NEt3 is described. Dendrimers 3 and 5 contain propargyloxy units as terminal groups, which can be transferred to Co2((CO)8 (6) to give the hexacarbonyldicobalt functionalized dendritic molecules Si{OCH2CH2CH2[(η-OCH2C=CH)CO2(CO)6]2}4 (7) and Si{OCH2CH2CH2SiMe-(OCH2CH2CH2SiMe[(η-OCH2C=CH)CO2(CO)6]2)2}4 (8). All compounds were characterized by elemental analyses, spectroscopic studies (IR,1H-, 13C{1H }-, 29Si{1H} NMR) as well as GPC investigations

The reaction of (η5-C5H4SiMe3)2TiCl2 (1) with HO(CH2)nC ≡ CR (2a: n = 1, R = H; 2b: n = 1, R = CH3; 2c: n = 1, R = CH2OH ; 3: n = 2, R = H; 4: n = 4, R = H) affords in toluene at 25 °C in the presence of NEt3 the monoalkyne-ol substituted titanocenes (η5-C5H4SiMe3)2Ti(Cl)[O(CH2)nC ≡ CR] (5a: n = 1. R = H; 5b: n = 1, R = CH3; 5c: n = 1, R = C H2OH; 6: n = 2, R = H; 7: n = 4. R = H ). Compound 5c reacts with one equivalent of 1 in the presence of NEt3 to yield (η5-C5H4SiMe3)2(Cl)Ti-OCH2C ≡ CCH2O -Ti(Cl)(η5-C5H4SiMe3)2 (8). In addition, compound 8 can be synthesized directly by treatment of (η5- C5H4SiMe3)2TiCl2 (1) with 0.5 equivalents of HOCH9C≡CCH2OH (2c) in the presence of NEt3. The reaction of (η5-C5H4SiMe3)2Ti(Cl)(OCH2C ≡ CCH3) (5b) with Co2(CO)8 (9) yields (η5-C5H4SiMe3)2Ti(Cl)[(η2-OCH2C ≡ CCH3)Co2(CO)6] (10). Treatment of 5b or 10 with HCl(aq) (11) leads to the formation of (η5-C5H4SiMe3)2TiCl2 (1) and HOCH2C ≡ CCH3 (2b) (reaction of 5b with 11) or (η5-C5H4SiMe3)2TiCl2 (1) and [(η2-HOCH2C ≡ CCH3)Co2(CO)6] (12) (reaction of 10 with 11). All compounds have been characterized by analytical and spectroscopic data (IR , 1H, 13C NMR, MS) and (η5-C5H4SiMe3)2Ti(Cl)(OCH2C ≡ CCH3) (5b) by X -ray analysis.

The synthesis and reactivity of non-coordinated and coordinated propargyl phosphanes are discussed. The isomerization of the propargyl unit in (R)P(Cl)(CH2C ≡ CH ) (3) (R = 2,4,6-tBu3-C6H2O) in the presence of NEt3 yields the allenyl substituted p roduct (R)P(Cl)(CH = C = CH2) (4). However, in the presence of HNEt2 the dimethylenecyclobutane 7 is formed. Different synthetic pathways for the preparation of LnMP(Ph)m(CH2C ≡ CH)3-m complexes (m = 2: LnM = (η5-C5H5)(CO)2Mn: 10a; LnM = (CO)5Cr: 10b; m = 1: LnM = (η5-C5H5)(CO)2Mn: 13a; LnM = (η5-C 5H4Me)(CO)2Mn: 13b) are described. The synthesis o f the alkynyl substituted phosphane compounds LnMP(Ph)m(C ≡ CR )3-m (m = 2: R = Ph, LnM = (η5-C5H5)(C O )2Mn: 20a; LnM = (CO )5 Cr: 20b; R nBu, LnM = (CO)5 Cr: 20c; m = 1: R = Ph, LnM = (η5-C5H5)(CO)2Mn: 22) was also possible. The reaction of (η5-C5H4Me)(CO)2,MnPPh (CH2C ≡CH)2 (13 b) with Co2(CO)8 affords in high yields (η5-C5H4Me)(CO)2MnPPh[(η2 -CH2C ≡ CH )Co2(CO )6]2 (15). All new com pounds have been characterized by analytical and spectroscopic data (IR , 1H -, 13C {1H }-, 31P { 1H } -NMR , MS) and (η5-C5H5)(CO)2MnP(Ph)(CH2C ≡ CH)2 (13a) by X -ray analysis.

The reaction of bifunctional neutral phosphenium ion complexes, containing a carbon-carbon triple bond next to a phosphorus-molybdenum multiple bond, with carbenes and to carbene isolobal organometallic fragments is discussed. So, the reaction of (R)(PhC=C)P=MoCp′(CO), (R = 2,4,6-′Bu3C6H2O; Cp′ = η5-C5H5: la; Cp′ = η5-C5Me5: 1b) with CH2,Ν2 (2) yields the three membered heterocyclic compound (3). 3 reacts with Co2(CO)8 to afford complex (5) in which the phenylethynyl building block is η2-side-on coordinated to a Co2(CO)6 fragment. Similar to the reaction of 1 with 2, 1 forms with Fe2(CO)9 (6), compound (7). In 7 the PMo double bond is coordinated in a η2 fashion to the 16-electron organometallic fragment Fe(CO)4. Using an excess of 6 and a higher temperature, the phosphorus-alkynyl-carbon σ-bond is cleaved, and cluster MoCp*Fe3(CO)8η3-PR)(C≡CPh) (8) is formed. The reaction of 1 with Cr(CO)5(THF) yields 10, a complex, in which the PhC≡C ligand is η2-coordinated to Cp′(CO)2Mo, and the Cr(CO)5 group forms a dative bond with the phosphorus atom. All new compounds have been characterized by analytical as well as by spectroscopic data (IR, 1H, 31P, 13C NMR, MS), compound 10 by an X-ray analysis.

The synthesis of tri(phenylethynyl)arsane (1) and -stibane (7) is discussed. Octacarbonyldicobalt reacts selectively with 1 or 7 to yield the η2-side-on co-ordinated phenylethynyl complexes (Ph–C=C)nE[(η2-C≡C–Ph)Co2(CO)6]3-n (E = As: n = 2: 3, n = 1: 4, n = 0: 5; E = Sb: n = 2: 8; n = 1: 9; n = 0: 10), which contain sterically hindered carbon-cobalt tetrahedrane cluster units. 3 gives upon heating {(Ph–C≡C)2As[(η2-C=C–Ph)Co2(CO)5]}2 (6) a compound containing a six-membered Co2As2C2 ring. All new compounds have been characterized by analytical and spectroscopic data (IR, 1H, 13C NMR), and (Ph –C≡C)As[(η2-C≡C–Ph)Co2(CO)6]2 (4) by X-ray analysis.

(η5-C5H5)2TiCl2 (1a) reacts with one equivalent of Li–C≡C–Si(CH3)3 to yield the mono alkynyl-substituted titanocene complex η5C5H5)2,Ti(Cl)[C≡C–Si(CH3)3] (2). The reaction of 2 with another equivalent of Li–C≡C–Si(CH3)3 gives the disubstituted compound (η5-C5H5)2Ti[C≡C–Si(CH3)3]2 (3f). In general, complexes of the type (η5-C5H4R)2Ti(C≡C–R′)2 (R = H, CH3, Si(CH3)3; R′ = C6H5, C2H5, nC3H7, nC4H9, ′C4H9, Si(CH3)3), 3-5, can be prepared by the reaction of η5-C5H4R)2,TiCl2 (1) and two moles of E–C≡C–R′ (E = BrMg, Na, Li; R, R′ = see above) to give the compounds 3-5 in yields of up to 95%. The reaction of 2-5 with X2 or HX yields the appropriate compounds η5-C5H4R)2TiX2 (X = F, Cl, Br) and H–C≡C–R′ or X–C≡C–R′.

(nC3H7)As(CN)2 (1) reacts with CO2(CO)8 (2) to yield the cluster 3 in which two (nC3H7)As fragments are coordinated to Co(CO)n (n = 1, 2, 3) groups. The cluster 3 has been characterized by analytical and spectroscopic data and by an X -ray analysis.

Phosphorustrihalides react with Na2[M2(CO)10] (M = Cr. Mo, W) to give phosphinidene complexes [(CO)5M]2P-Hal. These species are transformed into phosphorus(+I)-cheiate compounds [XXX]. = tropolonate or 8-hydroxychinolate.

Compounds RXHal2 (X = P, As, Sb) react with Na2[M2(CO)10] (M = Cr, Mo, W) to yield three types of products: A, [(CO)5M]2X-R containing trigonally planar coordinated X; C, [(CO)5M]3X-R containing coordinated metallacyclic ligands; B, [xxx] D, [(CO)5M]n (R)X = X (R) (n = 0, 1, 2, 3). The relation between these species, especially the one based on the valence tautomerism between A und B, is experimentally verified. Preparative, spectroscopic and X-Ray-structural results reveal a consistent picture of the relevant chemistry.

Complexes of dihalophosphanes LnM-P(R)(Hal)2 (LnM = 16-electron fragment e.g. Cp(CO)2Mn) undergo transformations into phosphinidene-, diphosphene- or diphosphanederivatives upon treatment with metallating agents (e.g. tBuLi/TMEDA). On the basis of many experimental observations a unified reaction scheme is proposed for these syntheses. The preparation and reactivity of diphosphane complexes LnM-(R)P(H) -(R)P(H)-MLn is discussed in some detail. Analytic, spectroscopic and X-ray techniques are used to establish the results. A prominent finding is the observation of an extremely long P-P distance (235.1(3) pm) for the sterically strained meso-[Cp(CO)2Mn]2(tC4H9)P(CH3) -(tC4H9)P(CH3)