bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthese und Struktur von Bis(trimethylstannyl)‐ und Bis(dimethylhalogenstannyl)aminen: zur Rolle des Stickstoff‐Elektronenpaares
Authors: Diemer Stefan , Noth Heinrich , Polborn Kurt , Storch Wolfgang 
Published: July 2007

Synthesis and Structure of Bis(trimethylstannyl) and Bis(dimethylhalostannyl) Amines: The Role of the Nitrogen Lone PairMonoaminostannanes RNH— SnMe3 (1) with substituents R = tBu, Mes, 2,6‐iPr2C6H3 are obtained by transmetallation from Me3SnX and RNH—Li, the distannylamines RN(SnMe3)2 (2) by transamination of Et2N —SnMe3 with RNH2, and bis(dimethylhalostannyl)amines R—N(SnMe2X)2 (8) by stannazane cleavage of 2 with Me2SnX2 or by SnC cleavage with BX3 (8n, o). Me2Sn(NtBuH)2, prepared from tBuNHLi and Me2SnBr2, decomposes with tBuNH2 elimination into the diazadistannetidine 4 already below room temperature. Information from multinuclear NMR spectra of type 2, 4, and 8 compounds ascertain the proposed relation between the value of the geminal coupling constant 2J(119Sn117Sn) of distannazanes and the Sn—N—Sn bond angle as determined by the X‐ray structure analysis of 2c and of (8a)2 as well as the participation of the electron pair at the nitrogen atom in bonding. 2c has C2 symmetry, contains a planar nitrogen atom with SnN bond lengths of 2.044 Å and an Sn—N—Sn bond angle of 125.0°. The aryl group stands perpendicular to the Sn2N plane. These data exclude any π interaction between the N atom and the substituents. 2c, therefore, represents an example of a tertiary amine with the lone electron pair at the nitrogen atom in a p‐type orbital. The supposed distannylamine (ClMe2Sn)2NMe (8a) is actually a dimer, whose unexpected structure contains a diazadistannetidine unit bearing two Me2SnCl2 groups at its nitrogen atoms in cis‐configuration. This arrangement allows the formation of weak intramolecular SnCl bonds.
Beiträge zur Chemie des Bors, 211. Zum Aufbau von Bor‐Germanium‐Bindungen mit Dimethylgermylen
Authors: Mayer Erwin P. , Nöth Heinrich , Rattay Winfried , Wietelmann Ulrich 
Published: July 2007

Contributions to the Chemistry of Boron, 211[1]. — On the Formation of Boron‐Germanium Bonds with Dimethylgermylene2‐(Dimethylgermyl)‐1,3,2‐benzodioxaborole (3) is formed by insertion of dimethylgermylene into the BH bond of catechol borane (2). According to the same principle, the trigermylborane 5 is obtained by insertion of three Me2Ge units into the BCl bond of chloro(2,2,6,6‐tetramethylpiperidino)borane (4). Me2Ge reacts with 9‐fluorenylidene(tetramethylpiperidino)‐borane 8 to yield the trigermaborolane 10, which is characterized by an X‐ray structure analysis.
Das Koordinationsverhalten der Stickstoffbasen R—CN (R = H, Cl, I, CH3) und des Pyridins gegenüber AsF5 in Lösung
Authors: Tornieporth‐Oetting Inis C. , Klapötke Thomas M. 
Published: July 2007

The Coordination Behaviour of the Nitrogen Bases R—CN (R = H, Cl, I, CH3) and Pyridine towards AsF5 in SolutionThe coordination behaviour of the nitriles R—CN (R = H, Cl, I, CH3) and of pyridine towards the strong Lewis acid AsF5 in solution is investigated and discussed on the basis of the hardsoft acid‐base (HSAB) principle. Solution equilibria are studied by means of 1H‐NMR spectroscopy. For the equilibrium of HCN, ICN, and AsF5 with the corresponding coordinated Lewis acid—Lewis base adducts the estimated value for the equilibrium constant is in good agreement with the experimental data.
Strukturaufklärung eines doppelsträngigen Polymers mittels Modellstudien
Authors: Godt Adelheid , Enkelmann Volker , Schlüter Arnulf‐Dieter 
Published: July 2007

Structure Elucidation of a Double‐Stranded Polymer by Using Model StudiesSyntheses and complete structural characterization (including constitution, configuration, conformation) of the double‐stranded compounds Ua‐5b, Ss‐5b, U‐7b, S‐7b, UUa‐8, SUs‐8, UUUaa‐9, USUas‐9, SUUsa‐9, and SSuss‐9 are described. These compounds contain up to three repeating units of the ladder polymer 3 and are therefore used as model compounds to elucidate interesting structural aspects of this polymer. A model for the spherical shape of 3 is presented. The molecular structures in the crystals of S‐7b, SUs‐8, Ua‐5b have been determined.
Synthesis of a Novel Optically Active C2‐Symmetric 2,2′‐Bipyridine
Authors: Bolm Carsten , Ewald Martina , Zehnder Margareta , Neuburger Markus A. 
Published: July 2007

AbstractOptically active 2,2′‐bipyridine (S,S)‐1 was synthesized by radical cyclization and a nickel(0)‐mediated coupling of enantiomerically pure bromopyridine (S)‐8. Palladium, copper, and cobalt complexes of 1 were prepared. The solid‐state structures of meso‐1 and 11 were determined by X‐ray crystal structure analysis.
Synthesis, Fluorescence, and Photostabilities of 3‐(Perfluoroalkyl)coumarins
Authors: Matsui Masaki , Shibata Katsuyoshi , Muramatsu Hiroshige , Sawada Hideo , Nakayama Masaharu 
Published: July 2007

AbstractThe regioselective reaction of coumarins 1 with bis(perfluo‐roalkanoyl) peroxides affords 3‐(perfluoroalkyl)coumarins 2 in moderate yields. The absorption and emission maxima of coumarins 2 show bathochromic shifts compared with the 3‐unsubstituted coumarins. The fluorescence intensities of 3‐(perfluoroalkyl)coumarins 2 are smaller than those of the 3‐unsubstituted ones. However, the photostabilities of coumarins 2 are higher than those of the 3‐unsubstituted ones.
Zur Kenntnis der thermischen Umlagerung des Bicyclo[1.1.0]butan‐Systems. Eine kinetische Studie des Übergangs von Tricyclo[4.1.0.02,7]heptanen in Bicyclo[3.2.0]hept‐6‐ene
Authors: Christl Manfred , Stangl Roland , Jelinek‐Fink Hans 
Published: July 2007

On the Thermal Rearrangement of the Bicyclo[1.1.0]butane System. A Kinetic Investigation of the Conversion of Tricyclo[4.1.0.02,7]heptanes into Bicyclo[3.2.0]hept‐6‐enesTricyclo[4.1.0.02,7]heptane (7), its 1‐ (20) and 2‐phenyl derivatives (22), tetracyclo[5.1.0.02,4.03,5]octane (17), 1,2,3,4‐tetrahydro‐1,2,3‐methenonaphthalene (25) as well as its 1‐ (35), 2‐ (32), and 3‐phenyl derivatives (27) have been thermolyzed in solution in the temperature range between 110 and 230° C. The activation parameters of these reactions have been determined. The parent hydrocarbon 7 is converted into bicyclo[3.2.0]hept‐6‐ene (11) in high yield, and the other substrates behave analogously, i.e. the cyclobutene derivatives 18, 21, 23, 26, 28, 33, 34, and 36 are formed. Arising from 27, the cyclobutene 28 is observed as intermediate, which is transformed rapidly to a mixture of the benzocycloheptenes 29 and 31. To undergo this ring enlargement, the other cyclobutenes require more severe conditions. The thermal rearrangements of 20, 22, and 27 are accompanied by parallel reactions, which have been identified as acid‐catalized processes in the case of 22 and 27 giving rise to the norcarene derivatives 24 and 30, respectively. In 2‐phenylmethenonanpthalene 32 two pathways to a cyclobutene derivative exist; they are found to be followed in a 82:18 ratio. The relative reaction rates of all substrates investigated can be interpreted in terms of a consistent mechanistic model. Accordingly, the tricyclo[4.1.0.02,7]heptane system is transformed in a concerted but highly asynchronous process to an (E,Z)‐1,3‐cycloheptadiene, which then undergoes a rapid conrotatory ring closure to yield the corresponding bicyclo[3.2.0]hept‐6‐ene.
2,3‐(Ethylenedisulfonyl)‐1,3‐butadiene, à Versatile Diels‐Alder Diene and Dienophile
Authors: Lee Shwu‐Jiuan , Peng Man‐Li , Lee Jui‐Chen , Chou Ta‐Shue 
Published: July 2007

Abstract2,3‐(Ethylenedisulfonyl)‐1,3‐butadiene (1) may be readily prepared from its stable 3‐sulfolene precursor 10. Compound 1 undergoes Diels‐Alder reactions with a number of dienophiles ranging from electron‐deficient to electron‐rich alkenes as well as an aldimine. It also reacts as both the diene and the dienophile in some [4 + 2] cycloadditions.
Reductive Transformations, 16[1] Electron Transfer and Regioselectivity in the Alkylation of a Hydrocarbon Mono‐ and Dianion
Authors: Müllen Klaus , Alexander Jürgen , Klabunde Kay‐Uwe , Klärner Frank‐Gerrit , Lund Henning , Lund Torben 
Published: July 2007

AbstractThe reductive alkylation of the pyrene isomer 1 affords bridged [14]annulenes (2) and 2a,3‐dihydro‐2a,3‐dialkyldicyclopenta[ef,kl]heptalenes (3). The involvement of an electron transfer (ET) in this reaction is demonstrated by optically pure electrophiles. Supporting evidence for ET processes is provided by cyclic voltammetric measurement of rate constants for both the ET process and the SN2 reaction. The choice of the electrophile is relevant not only for the importance of electron transfer, but also for the regioselectivity of the alkylation reaction.
Fluor‐ und Fluoroxodithietane
Authors: Viets Detlef , Waterfeld Alfred , Mews Rüdiger , Weiss Ilse , Oberhammer Heinz 
Published: July 2007

Fluoro‐ and Fluorooxodithietanes (1) was isolated from the reaction of 2,2,4,4‐tetrafluoro‐1,3‐dithietane (3) with CIF in an unpassivated monelcylinder. The hydrolysis of 1 gives (2): the trans derivative (2b) and the cis isomer (2a) are formed in a 4:1 ratio. (7) is oxidized by CIF at room temperature to give the known (8) in 87% yield. At 50°C from 8 and (9) is formed besides the ring cleavage products CF3SO2CF2SF4Cl (10) and CF3SO2CF2SF5 (11). The gasphase structure of 9 (e.d.) is described. (5) and (13) coordinate by the oxygen of the SO group to AsF5, with an unstable sulfonium salt is formed, while from the reaction of AsF5 and SbF5 with 8 (15 a, b, M = As, Sb) are isolated.
η1‐P‐ und η2‐OP‐gebundene (Ether‐phosphan)osmium(II)‐Komplexe und ihre gegenseitige Umwandlung
Authors: Lindner Ekkehard , Rothfuß Helmut , Fawzi Riad , Hiller Wolfgang 
Published: July 2007

η1‐P‐ and η2‐OP‐Bonded (Ether‐Phosphane)Osmium(II) Complexes and their Mutual ConversionReactions of cis‐Br2Os(CO)4 with the (ether‐phosphane) ligands 2a–f results in the formation of the cis,cis,trans‐complexes Br2Os(CO)2(P ∼ O)2 (3a–f). 3b crystallizes in the mono‐clinic space group P21/c with Z = 4. Irradiation of 3a–f leads to the cleavage of a further CO group and the formation of an OsO bond to give the mono(chelate) complexes Br2Os(CO)‐(PO) PO (5a–f), with one of the O,P ligands being bidentate. 5a–f exist as mixtures of different trans‐P (A,B) and cis‐P isomers (C–G). Dependent on the fact that a reversible cis/trans equilibrium or an irreversible trans → cis transformation is possible or that no trans‐P isomers are present at any temperature, 5a–f may be classified in three categories. Inter‐conversion of the isomers A–G results from dissociation of the η1‐P coordinated ether‐phosphane and concomitant occurrence of the 16e− species Br2Os(CO)(PO) (8). From temperature‐dependent 31P{1H}‐NMR spectroscopic investigations the temperature for the reversible opening of the metal‐oxygen contact is determined. The reversible opening leads to the complexes Br2Os(CO)(PO)2 (9) with a vacant coordination site depending on the Os–O bonding strength. 5a–f react with CO to give all‐trans‐Br2Os(CO)2(PO)2 (4a–f). The action of the ether‐phosphanes 2a–f on OsBr2(PPh3)4 (7) affords the bis(chelate) complexes Br2Os(PO)2 (6a–f) which add carbon monoxide to form all‐trans‐4a–f.
Tantaloxide durch Gasphasenhydrolyse, Druckhydrolyse und Transportreaktion aus 2H‐TaS2: Synthesen von TT‐Ta2O5 und T‐Ta2O5 und Kristallstruktur von T‐Ta2O5
Authors: Hummel Hans‐U. , Fackler Richard , Remmert Peter 
Published: July 2007

Tantalum Oxides by Gasphase Hydrolysis, Pressure Digestion, and Chemical Transport of 2H‐TaS2: Synthesis of TT‐Ta2O5, T‐Ta2O5 and X‐ray Structure Determination of T‐Ta2O5TT‐Ta2O5 is obtained by pressure digestion in water using 2H‐TaS2 as starting material at a temperature of 200°C followed by a dehydratization procedure of initially formed amorphous HTaO3. The X‐ray powder diagram of TT‐Ta2O5 revealed a hexagonal unit cell with space group P6/mmm and lattice constants a = 3.639, c = 3.901 Å. This material undergoes a phase transition during heating from 20 to 900°C. The resulting product is crystallizing orthorhombic with space group Pmm2 and lattice constants a = 43.997(8), b = 3.894(1), c = 6.209(3) Å and Z = 12. Single crystals of this phase (T‐Ta2O5) have been prepared by chemical transport reaction using TT‐Ta2O5 as starting material and NH4Cl as transport agent. The structure of T‐Ta2O5 consists of pentagonal‐bipyramidal coordinated tantalum atoms connected with distorted TaO6 octahedra. The Ta–O distances vary between 1.84 and 3.09 Å and the mean Ta–O distance is 1.99 Å.
Organoborierung von Tetrakis(trimethylsilylethinyl)stannan – Röntgenstrukturanalyse eines 5‐Stannaspiro[4.4]nona‐1,3,6,8‐tetraen‐Derivates[1]
Authors: Wrackmeyer Bernd , Kehr Gerald , Boese Roland 
Published: July 2007

Organoboration of Tetrakis(trimethylsilylethynyl)stannane – X‐ray Structure of a 5‐Stannaspiro[4.4]nona‐1,3,6,8‐tetraene DerivativeTetrakis(trimethylsilylethynyl)stannane (1) reacts with non‐cyclic trialkylboranes BR3 [2, R = Me (a), Et (b), Pr (c), iPr (d)] and 9‐alkyl‐9‐borabicyclo[3.3.1]nonanes[2e (alkyl = Et), 2f (alkyl = neopentyl)] to give the 3,8‐dialkyl‐2,7‐bis(dialkylboryl)‐1,4,6,9‐tetrakis(trimethylsilyl)‐5‐stannaspiro[4.4]nona‐1,3,6,8‐tetraenes 5a to f in high yield. The reaction proceeds stepwise, and intermediates as well as final products were characterized by 1H, 11B, 13C, 29Si, 119Sn NMR spectroscopy. According to an X‐ray structure analysis of 5f · 0.5 CH2Cl2 (space group P2/c) the endocyclic CSnC bond angles are small [84.9(2) and 84.2(2)°] and the two five‐membered rings are not exactly planar. Steric crowding causes a strong twist of the skeleton of the other ring systems. The agreement between solid‐state and liquid‐phase NMR data shows that main structural features are retained in solution.
Reaktionen an Silicium‐Silicium‐Bindungen, 2[1] Trichlorsilylierung von tert‐Butyldichlorphosphan und tert‐Butylbis(trimethylsilyl)phosphan mit Hexachlordisilan: Ein Weg zu neuen bifunktionellen (Trichlorsilyl)phosphanen
Authors: Martens Rainer , Mont Wolf‐Walther Du 
Published: July 2007

Reactions of Silicon‐Silicon Bonds, 2[1]. – Trichlorosilylations of tert‐Butyldichlorophosphane and tert‐Butylbis(trimethylsilyl)phosphane with Hexachlorodisilane: Synthesis of New Bifunctional (Trichlorosilyl)phosphanesDi‐tert‐butyl(trimethylsilyl)phosphane (1) and tert‐butylbis(trimethylsilyl)phosphane (3) react with one equivalent of hexachlorodisilane with exchange of one trimethylsilyl group by a trichlorosilyl group under mild conditions to give di‐tert‐butyl(trichlorosilyl)phosphane (2) and tert‐butyl(trichlorosilyl)(trimethylsilyl)phosphane (4) in fair yields. tert‐Butylbis(trichlorosilyl)phosphane (5) is available from tert‐butyldichlorophosphane without organometallic reagents and solvents by simple reductive trichlorosilylation with the help of two equivalents of hexachlorodisilane. 5 is a useful precursor for phosphaalkane synthesis: with pivaloyl chloride, 5 leads to tert‐butyl‐[tert‐butyl(trichlorosilyloxy)methylene]phosphane (6). From 4 with pivaloyl chloride mainly 6 and some known tert‐butyl[tert‐butyl(trimethylsilyloxy)methylene]phosphane (7) are formed.
„2,2′‐Bisdimedonyliden” – ein neues elektrophiles Olefin
Authors: Schank Kurt , Fünfrocken Michael 
Published: July 2007

„2,2′‐Bisdimedonylidene‘ – a Novel Electrophilic OlefinHerrn Professor Michael Hanack zum 60. Geburtstag gewidmet.
The title compound has been prepared unambiguously by dehydrogenation of known „2,2′‐bisdimedonyl’ (8). Its typical electrophilic character leads to additions of various nucleophiles which prove the molecular structure. Physical data are in disagreement with those mentioned in the literature.
Synthesen mit dem Reagenz Pentamethylcyclopentadienylbromid/Silbertetrafluoroborat: Das Pentamethylcyclopentadienyl‐Kation als reaktive Zwischenstufe
Authors: Jutzi Peter , Mix Andreas 
Published: July 2007

Syntheses with the Reagent Pentamethylcyclopentadienyl Bromide/Silver Tetrafluoroborate: The Pentamethylcyclopentadienyl Cation as Reactive IntermediatePentamethylcyclopentadienyl bromide 1 reacts with silver tetrafluoroborate with abstraction of the halide ion to form pentamethylcyclopentadienylium tetrafluoroborate (2). The 4π‐antiaromatic cation in 2 can be trapped with different nucleophiles. Thus, 2 reacts with methanol to give 5‐methoxy‐1,2,3,4,5‐pentamethyl‐1,3‐cyclopentadiene (4). In the presence of methylamine, dimethylamine, or diethylamine, the corresponding pentamethylcyclopentadienyl‐substituted amines 5, 6, and 9 are formed. Trapping of 1 with pyridine or dimethyl sulfide leads to the ionic compounds 7 and 8, respectively. The reaction of 2 with sterically crowded amines leads to tetramethylfulvene (3).
Oxidative Addition von Aldehyden und Schiffbasen an Ru3(CO)12
Authors: Scott Bohle D. , Breidt Verena F. , Powell Anne K. , Vahrenkamp Heinrich 
Published: July 2007

Oxidative Addition of Aldehydes and Schiff Bases to Ru3(CO)12Aldehydes show a wide variation of their reactive behaviour towards Ru3(CO)12. Aliphatic and simple aromatic aldehydes form simple oxidative addition products Ru3(CO)10(μ‐H)(μ‐RC = O) (1) either not at all or in low yields as impure compounds, while under forcing conditions dinuclear ruthenium μ‐carboxylate complexes or the hydride H2Ru4(CO)13 are formed. Electron‐rich aldehydes give good yields of cluster type 1 (R = p‐MeOC6H4, p‐Me2NC6H4, ferrocenyl). Schiff bases behave similarly, their oxidative addition products being Ru3(CO)10(μ‐H)(μ‐RC = NR′) (10, R = C6H5, p‐MeOC6H4, p‐Me2NC6H4, R′ = C6H5, p‐MeC6H4). Of the ortho‐substituted benzaldehydes, the methoxy compound produces clusters 6 and 7 resulting from aldehyde oxidative addition and aromatic ortho metalation. Salicylaldehyde and its p‐tolylimine give the compounds Ru3(CO)8(μ‐η2‐OC6H4CH = X)2 (9, 11, X = O, NC6H4Me) with a bridging phenolate and a terminally bound aldehydic O or Schiff base NR function. 3‐Pyridinecarbaldehyde reacts quickly with Ru3(CO)12 to give products 8 derived from pyridine CH rather than aldehyde CH oxidative addition. The crystal structures of 9 and 11 were determined.
Organische Synthesen mit Übergangsmetall‐Komplexen, 58. Heptafulvenylcarben‐Komplexe von Chrom und Wolfram. – Azaspiro[4]‐Anellierung an 1‐Metalla‐1,3‐diene mit Isocyaniden; Liganden‐Abspaltung mit Pyridin oder durch Thermolyse
Authors: Aumann Rudolf 
Published: July 2007

Organic Syntheses via Transition Metal Complexes, 58[1]. – Heptafulvenylcarbene Complexes of Chromium and Tungsten. – Azaspiro[4] Anellation to 1‐Metalla‐1,3‐dienes with Isocyanides; Displacement of Ligands by Pyridine or by Thermolysis*(Cycloheptatrien‐1‐ylmethyl)carbene complexes LnM = C(OEt)CH2‐c‐C7H7 3 [LnM = Cr(CO)5 (a), W(CO)5 (b)] are transformed into heptafulven‐8‐ylcarbene complexes LnM = C(OEt)CH = c‐C7H7 5 in two steps. The first step involves the formation of (tropyliummethyl)carbene complexes [LnM = C(OEt)CH2‐c‐C7H6]+ [BF4]‐ 4 by a hydride abstraction from the cycloheptatriene ring of 3 with [Ph3C]+ [BF4]‐ (4a, 4b: 70%). 4 is deprotonated with Et3N to give 5 (5a: 89%; 5b: 92%). 5 adds one equivalent of cyclohexyl isocyanide (6) to the LnM = C – C = C unit via the intermediate ketenimine complexes LnM[c‐C6H11N = C = C(OEt) – CH = c‐C7H6] 7, which cyclize spontaneously and form the (thermolabile) azaspiro[4.6]undecatetraene complexes 8 (8a: 91%; 8b: 93%). The reaction of 8a, b with pyridine leads to the disengagement of a pyrrole 10 in almost quantitative yields. Thermolysis of 8a, b in the absence of pyridine gives an azulene 12.
Catalytic Enantioselective Conjugate Addition of Dialkylzinc Compounds to Chalcones
Authors: Bolm Carsten , Ewald Martina , Felder Marcel 
Published: July 2007

AbstractConjugate addition of diethylzinc to enones is catalyzed by a complex derived from Ni(acac)2 and C2‐symmetric 2,2′‐bipyridine 3 or chiral pyridines 5–12. The products are obtained with optical purities up to 89% ee. A strong positive nonlinear relationship between the enantiomeric excess of the ligand and the ee of the product has been observed. The factors which govern catalyst activity and enantioselectivity have been investigated.
Substituierte 2,5‐Dihydro‐1,2,5‐oxoniadiboratole, cis‐1,2‐Diborylalkene und 1,2,5‐Oxadiborolane – Herstellung und Charakterisierung
Authors: Köster Roland , Seidel Günter 
Published: July 2007

Substituted 2,5‐Dihydro‐1,2,5‐oxoniadiboratoles, cis‐1,2‐Diborylalkenes, and 1,2,5‐Oxadiborolanes – Preparation and CharacterizationThe potassium salts magnified image (A: R = R′ = Et; B: R2 = C8H14, R′ = Me; C: R2 = C8H14, R′ = Et) react with various electrophiles (H+, R+, Me3ElIV+) to form substituted 1,3,2‐diboroxanes (1, iso8b) including 1,2,5‐oxadiborolanes (2, 4, 6, 9, 10), dialkylvinylboranes (1'), 2,5‐dihydro‐1,2,5‐oxoniadiboratoles (3, 5) and cis‐1,2‐diborylalkenes (7, 8). In particular, A–C react with HCl (as Me3NHCl/THF or HCl/Et2O) to give O[B(Et)C(Et) = CHR]2 (1a: R = Me; 1b: R = Et), R2BCR′ = CHEt (1'a: R = R′ = Et; 1'b: R2 = C8H14, R′ = Me; 1'c: R2 = C8H14, R′ = Et) and magnified image (2a: R,R′ = Et; 2b: R2 = C8H14, R′ = Me; 2c: R2 = C8H14, R′ = Et). With MeI in THF the cyclic compounds magnified image (3a) or magnified image (4b/4'b: R = Me; 4c/4'c: R = Et) and with Et3O · BF4 in CH2Cl2 the heterocycle magnified image‐ (5a) and cis‐EtOB(C8H14)C(Et) = C(Et)BEt (5c) and/or magnified image (6b: R = Me; 6c: R = Et) are obtained. The reactions of A with ClElIVMe3 (ElIV = Si, Ge, Sn) lead to cis‐Et2BC(Et) = CB(Et)OE1IVMe3 [ElIV=Si(7a), Ge (8a)] and to cyclic magnified image (9a). The salts B and C react with ClElIVMe3 (ElIV = Si, Ge) to form cis‐C8H14BC(R) = C(Et)B(Et)OElIVMe3 (ElIV = Si: 7b: R = Me; 7c: R = Et; ElIV = Ge: 8b: R = Me, 8c: R = Et). On heating 8b isomerizes to cis‐Me3GeC(Me) = C(Et)B(Et)OBC8H14 (iso8b). From B and C with ClSnMe3 the substituted 1,2,5‐oxadiborolanes magnified image (10b/10'b: R = Me; 10c: R = Et) are obtained together with (C8H14B)2O.
Synthese, Kristallstruktur und fluktuierendes Verhalten von cis‐Cl2Ru(CO)(P∽O)(PˆO) mit cis‐ständigen (Ether‐Phosphan)‐Liganden
Authors: Lindner Ekkehard , Möckel Andrea , Mayer Hermann August , Fawzi Riad 
Published: July 2007

Synthesis, Crystal Structure, and Fluxional Behavior of cis‐Cl2Ru(CO)(P∽O)(PˆO) with cis‐Positioned (Ether‐Phosphane) LigandsReaction of the ether‐phosphane ligands 2a–c with Cl2Ru‐(PPh3)3 (1) results in the formation of the bis(chelate) complexes trans‐Cl2Ru(PˆO)2 (3a–c) (P∽O = η1‐P‐coordinated; Pb̂O = η2‐O,P‐coordinated). With CO both Ru–O bonds are cleaved to give all‐trans‐Cl2Ru(CO)2(P∽O)2 (4a–c). The mono(chelate) complexes 5a–c are obtained from stoichiometric amounts of 3a–c and 4a–c. Upon heating the kinetically controlled products 5a–c are transformed into the thermodynamically more stable isomers cis‐Cl2Ru(CO)(P∽O)(PˆO) (6a–c). Both 5a–c and 6a–c show fluxional behavior. The higher coalescence temperatures and estimated ΔG≠ values of 6a–c (75, 67, and 70°C, respectively) compared to 5a–c (55, 0, and ‐10°C, respectively) indicate different exchange mechanisms for 5 and 6. According to an X‐ray structure analysis, 6b crystallizes in the monoclinic space group P21/c with Z = 4. The action of CO on 6a–c affords the cis,cis,trans complexes 7a–c.
Kohlenwasserstoffverbrückte Komplexe, XXV[1] C–C‐Kupplung von anionischen Tricarbonylmangan‐Komplexen cyclischer Polyene mit kationischen Tropylium‐Metallverbindungen; Darstellung und Struktur von (OC)3Mn(μ‐η5:η6‐C7H8–C7H7)M(CO)3, (OC)3Mn(μ‐η5:η6‐C8H10–C7H7)M(CO)3 und (OC)3Mn(μ‐η5:η6‐C8H8–C7H7)M(CO)3(M = Cr, Mo, W)
Authors: Wieser Michael , Sünkel Karlheinz , Robl Christian , Beck Wolfgang 
Published: July 2007

Hydrocarbon‐Bridged Complexes, XXV[1]. – C–C Coupling of Anionic Tricarbonyl Manganese Complexes of Cyclic Polyenes with Cationic Tropylium Metal Compounds; Preparation and Structure of (OC)3Mn(μ‐η5:η6‐C7H8‐C7H7)M(CO)3, (OC)3Mn(μ‐η5:η6‐C8H10–C7H7)M(CO)3, and (OC)3Mn(μ‐η5:η5‐C8H8–C7H7)M(CO)3 (M = Cr, Mo, W)The addition of the anionic complexes [(η4‐C7H8)Mn(CO)3]‐, [(η4‐C8H10)Mn(CO)3]‐ and [(η4‐C8H8)Mn(CO)3]‐ to the cations [(η7‐C7H7)M(CO)3]+ (M = Cr, Mo, W) gives the hydrocarbon‐bridged complexes (OC)3Mn(μ‐η5:η6‐C7H8–C7H7)M(CO)3, (OC)3Mn(μ‐η5:η6‐C8H10–C7H7)M(CO)3, and (OC)3Mn(μ‐η5:η6‐C8H8–C7H7)M(CO)3 (M = Cr, Mo, W). The structures of 4b and 6a have been determined by X‐ray diffraction.