bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthese und Kristallstrukturen von Carbonyleisen‐ und Cyclopentadienyleisen‐Zweikernkomplexen des 2,3‐Diethyl‐1,4‐dihydro‐1,4‐dimethyl‐1,4‐diboranaphthalins
Authors: Schulz Hartmut , Pritzkow Hans , Siebert Walter 
Published: July 2007

Synthesis and Crystal Structures of Carbonyliron and Cyclopentadienyliron Dinuclear Complexes of 2,3‐Diethyl‐1,4‐dihydro‐1,4‐dimethyl‐1,4‐diboranaphthalene*Reactions of the 1,4‐Diboranaphthalene derivative 1a with (CO)3Fe(C8H14)2 lead to the orange anti dinuclear complex [(CO)3Fe(η6, η4‐1a)Fe(CO)3] (4a) and to the cherry‐red syn complex [(CO)3Fe(η4, η61a)Fe(CO)2] (5a). The X‐ray structure of 5a reveals an Fe—Fe interaction (2.98 Å), 1a reacts with [(C5H5)Fe(C8H12)]2Zn to give the 30‐VE triple‐decker 7a, in which the diene of the benzo ring can be complexed with a Fe(CO)3 moiety to yield the trinuclear complex 9a.
Synthesis and Reactivity of Mixed Arene Halides of Niobium(I). Crystal and Molecular Structure of Nbmes2 and [Nbmes2(CO)][Nb2(μ‐I)3(CO)8]
Authors: Calderazzo Fausto , Pampaloni Guido , Rocchi Lucia , Gingl Franz , Strähle Joachim 
Published: July 2007

AbstractBis(mesitylen)niobium(0), Nbmes2, prepared via the NbCl5/Al/AlCl3/mes system by exaustive reduction in the presence of 1,2‐dimethoxyethane or tetrahydrofuran as previously reported, has been studied by X‐ray diffraction methods. The sandwich molecule has parallel, substantially planar, aromatic rings, in an eclipsed conformation. Nbmes2 is oxidized to Nbmes2X by reaction with 1,1‐dimethyl‐4,4′‐bipyridinium halides [methylviologen halides, mvX2 (X = Cl, I)]. The reaction of both halo compounds with CO yielded the niobium(I) derivatives [Nbmes2(CO)] [Nb2(μ‐X)3(CO)8]. In the case of X = I an IR study at low temperature has shown the presence of intermediate carbonyl compounds, presumably Nbmes2I(CO) and [Nbmes2(CO)]+. The ionic iodide derivative was shown by X‐ray diffraction methods to consist of discrete [Nbmes2(CO)]+ cations and [Nb2(μ‐I)3(CO)8]‐ anions. The two mesitylene groups in the cation are bent and in an eclipsed conformation.
Metallkomplexe mit funktionalisierten Schwefel‐Liganden, III. Reaktionen von (Ph3P)2Pt(η2‐C2H4) mit acyclischen und cyclischen Thiosulfinaten: Platin(II)‐thiolato‐Komplexe mit Sulfenato‐Liganden. Kristallstrukturanalyse von (4‐Sulfido‐1‐butansulfenato‐S,S′)‐bis(triphenylphosphan)platin(II)
Authors: Weigand Wolfgang , Bosl Gabriele , Robl Christian , Amrein Walter 
Published: July 2007

Metal Complexes of Functionalized Sulfur‐Containing Ligands, III[1]. – Reactions of (Ph3P)2Pt(η2‐C2H4) with Acyclic and Cyclic Thiosulfinates: Platinum(II)‐thiolato Complexes with Sulfenato Ligands. Crystal Structure Determination of (4‐Sulfido‐1‐butanesulfenato‐S,S′)bis(triphenylphosphane)platinum(II) magnified imageOxidative addition of acyclic thiosulfinates R′–S(O)–S–R (1a: R′ = R = CH3; 1b: R′ = R = Ph; 1c: R′ = R = p‐CH3C6H4;1d: R′ = p‐ClC6H4, R = C6H5) to (Ph3P)2Pt(η2‐C2H4) (4) leads to the monomeric trans‐configurated complexes (Ph3P)2Pt[S(O)R′](SR) (5a–d) which loose one PPh3 ligand in solution and form the dimetallic thiolato‐bridged compounds [(Ph3P)Pt[S(O)R′](μ‐SR)]2. The cyclic thiosulfinates 1,2‐dithiane S‐oxide (2) and 1,4‐dihydro‐2,3‐benzodithiine S‐oxide (3) react with 4 to yield the monomeric seven‐membered chelate magnified image(7) and the dimetallic complex [(Ph3P)Pt–S(O)–CH2–C6H4–CH2–μ‐S]2 (8), respectively. In 7, characterized by X‐ray diffraction, a tetrahedral distortion of the square planar coordination of the platinum(II) atoms is remarkable; the planes Pt,P(1),P(2) and Pt,S(1),S(2) form an angle of 16.1°.
Isocyanid‐ und Heteroallen‐verbrückte Metallkomplexe, IX. Di‐ und Trieisenkomplexe mit funktionellen Isocyanidbrücken
Authors: Christian Götz , Lentz Dieter , Hartl Hans , Fehlhammer Wolf Peter 
Published: July 2007

Isocyanide‐ and Heteroallene‐Bridged Metal Complexes, IX[1,2]. – Di‐ and Triiron Complexes with Functional Bridging IsocyanidesThe reactions of ten mainly functional isocyanide dichlorides RN = CCl2 with Na[FeCp(CO)2] in tetrahydrofuran give mono‐isocyanide derivatives [Fe2(Cp)2(CO)3CNR] (1 a–g) of [Fe‐Cp(CO)2]2 in which the isocyanide occupies a bridging position. In three cases also minor amounts of diisocyanide complexes [FeCp(μ‐CNR)CO]2 (2c, 2e, 8) have been isolated. The chlorocarbonyl‐substituted aryl isocyanide dichlorides and pentafluorophenyl isocyanide dichloride in addition suffer (CO)Cl/ and F/ metal exchange, respectively, with formation of μ3‐isocyanide‐bridged triiron complexes (4 a–c, 7) via the intermediates 5 and 6, 7 has been studied by X‐ray analysis.
Monomere und dimere 1,3‐Diaza‐2‐phosphaallyllithium‐Komplexe: Strukturen und ambidente Reaktivität
Authors: Detsch Ralph , Niecke Edgar , Nieger Martin , Schoeller Wolfgang W. 
Published: July 2007

Monomer and Dimer 1,3‐Diaza‐2‐phosphaallyllithium Complexes: Structures and Ambident Reactivity*Metallation of the NH‐functional amino(imino)phosphanes Mes*NPNHR (R = CPh3, Ad, tBu) 1a–c yields the 1,3‐diaza‐2‐phosphaallyllithium compounds 2a–c. The crystal structure shows an ether‐stabilized monomer of 2a and a solvent‐free dimer with an eight‐membered ring in the case of 2b, c. The reaction of 2b with chlorodiphenylphosphane yields, dependent on the reaction conditions, (phosphanylamino)iminophosphane 3 or bis(imino)phosphanylphosphorane 4. The structural and reactivity is discussed on the basis of ab initio calculations.
Mehrstufige reversible Redoxsysteme, LVIII. 2,5‐Bis(cyanimino)‐2,5‐dihydrothieno[3,2‐b]thiophene – ein neuer Acceptortyp: Synthese und allgemeine Eigenschaften
Authors: Günther Erhard , Hünig Siegfried 
Published: July 2007

Multistep Reversible Redox Systems, LVIII[1]. – 2,5‐Bis(cyanoimino)‐2,5‐dihydrothieno[3,2‐b]thiophenes – a New Acceptor Type: Synthesis and Common PropertiesThe synthesis of a variety of substituted 2,5‐bis(cyanoimino)‐2,5‐dihydrothieno[3,2‐b]thiophenes (4) and the corresponding diones (5) is described. Different substituents on the acceptors 4 and 5 allow the redox potentials of these reversible two‐step redox systems to be varied over a wide range.
Epoxidation of Enamines by Dimethyldioxirane: Formation of 1,4‐Dioxanes by Enamine Epoxide Dimerization
Authors: Adam Waldemar , Peters Eva‐Maria , Peters Karl , Schnering Hans Georg Von , Voerckel Volkmar 
Published: July 2007

AbstractThe 1,4‐dioxanes 3a–f, which constitute dimers of the enamine epoxides 2a–f, were obtained in excellent yields as crystalline products during the oxygen transfer to the corresponding enamines by dimethyldioxirane (DMD) in acetone. In methanol at –78°C, enamine 1b gave with dimethyldioxirane the β‐hydroxy acetal 4b as the expected trapping product of the intermediary enamine epoxide 2b.
Stabilisierung von Uran(IV)‐Alkylen durch raumerfüllende Chelatliganden: Molekülstruktur von [PhC(NSiMe3)2]3UMe
Authors: Wedler Michael , Knösel Friedrich , Edelmann Frank T. , Behrens Ulrich 
Published: July 2007

Stabilization of Uranium(IV) Alkyls by Bulky Chelating Ligands: Molecular Structure of [PhC(NSiMe3)2]3UMeChelate ligand‐stabilized uranium σ‐methyl complexes are obtained in good yields by treatment of [RC6H4C‐(NSiMe3)2]3UCl (1) with methyllithium. The molecular structure of [PhC(NSiMe3)2]3UMe (3a) has been determined by X‐ray crystallography. A long uranium – carbon bond [249.8(5) pm] indicates steric crowding in the molecule. Analogously the dimethyluranium complex [(CF3)3C6H2C(NSiMe3)2]2UMe2 (4b) is prepared from [(CF3)3C6H2C(NSiMe3)2]2UCl2 and two equivalents of methyllithium. Reaction of 1 with NaBH4 yields the tetrahydroborates [RC6H4C(NSiMe3)2]3UBH4 (5). The strongly temperature‐dependent 1H‐NMR spectra of the complexes 1 and 3 have been studied in detail.
Spektroskopischer Nachweis eines Bis(amino)silylens
Authors: Veith M. , Werle E. , Lisowsky R. , Köppe R. , Schnöckel H. 
Published: July 2007

Spectroscopic Identification of a Bis(amino)silyleneThe photolysis of the silicon diazide 3a in benzene solution and in an Ar matrix is described. Both irradiations cause the elimination of 3 equivalents of N2. Loss of N2 from 3a in benzene leads to the formation of the analytically investigated product or products 4 of uncertain structure. However, the matrix photolysis of 3a results in a compound which is stable up to 77 K and has been identified as the bis(amino)silylene 2d by comparison of its IR spectra with those of the homologous Sn and Ge compond.
Wasserstoffübertragungen, 20[1a] Konkurrierende pericyclische Reaktionen von Dihydroarenen mit gespannten Cycloalkenen und ‐alkinen
Authors: Gerres Thomas , Heesing Albert 
Published: July 2007

Hydrogen Transfer Reactions, 20[1a]. – Competitive Pericyclic Reactions of Dihydro Arenes with Strained Cycloalkenes and CycloalkynesWhile several highly strained cycloalkenes and cycloalkynes react with dihydroarenes to give products of Diels‐Alder or ene reactions only, 7 dehydrogenates two dihydroarenes as well. Semiempirical AM1 calculations on the transition structures for the [4 + 2] cycloadditions and the hydrogen transfer reactions show the independence of their geometry from the starting compounds. The preference for dehydrogenations by 7 is caused by both steric and solvent effects.
Benzoanellated centropolyquinanes, 11. Synthesis of tribenzotriquinacene and some centro‐substituted derivatives
Authors: Kuck Dietmar , Lindenthal Thomas , Schuster Andreas 
Published: July 2007

AbstractThe syntheses of tribenzotriquinacene (1a) and five centro‐substituted derivatives, 1b–1e and 1g, as well as of the related diindan 13 are reported. The three‐step synthetic sequences include the reduction of suitably substituted 2‐benz‐hydryl‐1,3‐indandiones 3 to the corresponding 1,3‐indandiols 4 and the twofold cyclodehydration of the latter to close two additional five‐membered rings at a time. Although the yields of the cyclodehydration step 4 · 1 are only low to moderate (10–33%), the overall approach allows the preparation of 5–50‐gram amounts of the centropolyindans in most cases by starting from simple 1,3‐indandiones 2a–2c. This includes the new synthesis of the parent tribenzotriquinacene (1a). The related Cs‐symmetrical diindan, 4b,9,9a,10‐tetrahydroindeno[1,2‐a]indene (13), has been prepared in high yield by using the same cyclodehydration technique. Scope and limitations of the double cyclodehydration strategy are described concerning the synthesis of 1,3‐indandiones with bulky substituents at C–2 and the cyclization of 1,3‐indandiols with an aptitude to undergo heterolytic cleavage of an exocyclic C–2–C‐α bond, in particular 4f. The course of the reduction of the 2,2‐disubstituted 1,3‐indandiones with lithium aluminum hydride is discussed on the basis of the stereochemistry of the product 1,3‐indandiols.
Mass‐spectrometric characterization of isomeric NNCCN and NCNCN Ions and neutrals
Authors: Muedas César A. , Sülzle Detlev , Schwarz Helmut 
Published: July 2007

AbstractNeutralization‐reionization mass spectrometry as well as charge reversal and collisional activation experiments serve to distinguish and assign the connectivities NNCCN and NCNCN to isomeric pairs of anions, neutral radicals and cations of C2N3. Loss of N2 to generate C2N+ is the critical discriminant, and the assignment is further substantiated by subjecting these fragment ions to collisional activation experiments by using tandem‐mass spectrometry facilities.
CO2‐Aktivierung an Übergangsmetallzentren: Simulation enzymatischer CO2‐Fixierungs‐ und Transferreaktionen durch elektronenreiche (Diazadien)magnesium‐ und ‐mangan‐Komplexe
Authors: Walther Dirk , Ritter Uwe , Undeutsch Zzbernd , Kempe Rhett , Sieler Joachim 
Published: July 2007

Activation of CO2 at Transition‐Metal Centres: Simulation of Enzymatic CO2 Fixation and Transfer Reactions by Electron‐Rich (Diazadiene)magnesium and ‐manganese ComplexesElectron‐rich diazadiene complexes of Mg and Mn can be used as model compounds for enzymatic carboxylation reactions e.g. the „dark reaction”︁ of the photosynthesis or in biotinedependent CO2 conversion reactions. The activity of the complexes to fix and transfer carbon dioxide strongly depends on the nature of the metal (Mg and Mn are active central atoms, other transition metals are inactive), the π aciditiy of the chelate ligand, and the structure of the complexes. The dimeric manganese complex IIa, the structure of which could be determined by X‐ray structure analysis, is one of the most active compounds. NMR studies reveal that the CO2 transfer to substrates with active C—H bonds takes place in the coordination sphere of the metal atom. Carrier of activated CO2 is the N—COO group.
Bis[bis(trimethylsilyl)methyl]galliumbromid und monomeres {Bis[bis(trimethylsilyl)methyl]gallium}[tris(trimethylsilyl)silyl]tellurid [(Me3Si)2CH]2Ga–TeSi(SiMe3)3
Authors: Uhl Werner , Layh Marcus , Becker Gerd , Klinkhammer Karl Wilhelm , Hildenbrand Thomas 
Published: July 2007

Bis[bis(trimethylsilyl)methyl]gallium Bromide and Monomeric {Bis[bis(trimethylsilyl]methyl]gallium} [Tris(trimethylsilyl)silyl]telluride [(Me3Si)2CH]2Ga–TeSi(SiMe3)3Bis[bis(trimethylsilyl)methyl]gallium bromide GaBr[CH(SiMe3)2]2 (4), prepared from Ga2Br4 · 2 dioxane and bis(trimethylsilyl)‐methyllithium in the molar ratio of 1:3, reacts with the sterically high‐shielded lithium tris(trimethylsilyl)silyltelluride · DME to yield [(Me3Si)2CH]2Ga–TeSi(SiMe3)3 (5). 5 can also be synthesized by a metathetic reaction between tetrakis‐[bis(trimethylsilyl)methyl]digallium(4) and bis[tris(trimethylsilyl)silyl]ditellane in toluene at 100°C. A crystal structure determination shows the compound to be monomeric in the solid state and the atoms of the central C2Ga–TeSi moiety to lie in the mirror plane of the molecule. The short Ga–Te distance of 253.5(1) pm as well as a hindered rotation (ΔErot ≈︁ 50 kJ · mol‐1) as detected by NMR measurements might be interpreted in terms of a π interaction between gallium and tellurium.
Polycyclische Verbindungen aus 2,5‐Norbornadien, Isopropylbenzol und Dehalogenierungs‐Produkten von Dihalogeno(diorganylamino)boranen. Reaktion von Bis(diisopropylamino)phenylboran mit Na/K‐Legierung und Difluor(diisopropylamino)boran
Authors: Maringgele Walter , Seebold Uwe , Meller Anton , Dielkus Sven , Pohl Ehmke , Herbst‐Irmer Regine , Sheldrick George M. 
Published: July 2007

Polycyclic Compounds from 2,5‐Norbornadiene, Isopropylbenzene, and Dehalogenation Products of Dihalogeno(diorganylamino)boranes. Reaction of Bis(diisopropylamino)phenylborane with Na/K Alloy and Difluoro(diisopropylamino)boraneIn the reaction of 2,5‐norbornadiene with Na/K alloy and dichloro(diisopropylamino)borane the species 1 was isolated, which contains six boron atoms in two triborolane rings. From isopropylbenzene and the dehalogenation products of (diisobutylamino)difluoroborane the ethenodiborolodiborol system 2 was isolated. When bis(diisopropylamino)phenylborane is treated with F2BN(i‐C3H7)2 and Na/K alloy the diborane(4) derivative 5 and 1,1,2,2‐tetrakisborylethane (6) are formed together with bis(diisopropylamino)fluoroborane (7). NMR (1, 11B, 13C, 19F) and MS data are given; for 1, 2, 5, and 6 the X‐ray structure analyses were performed.
Zink‐Komplexe von Tris(2‐pyridyl)phosphan und Tris(2‐pyridyl)arsan
Authors: Gregorzik Ralf , Wirbser Joachim , Vahrenkamp Heinrich 
Published: July 2007

Zinc Complexes of Tris(2‐pyridyl)phosphane and Tris(2‐pyridyl)arsaneReactions of zinc salts with the two title ligands are described which reveal several dissimilarities in their coordination behavior. From tris(2‐pyridyl)phosphane (1) and the zinc halides compounds with an L2Zn3 stoichiometry are isolated which, according to their Raman spectra, have the constitution [LZnHal]2[ZnHal4]. With tris(2‐pyridyl)arsane (2) the zinc halides form the 1:1 complexes LZnHal2. With Zn(SCN)2 and 1 only the L2Zn2+ species can be observed, while 2 produces the molecular complex LZn(SCN)2. Both 1 and 2 form a neutral 1:1 compound with Zn(NO3)2 which was shown for 1 · Zn(NO3)2 by an X‐ray structure analysis to consist in the solid state of octahedral complexes containing tridentate 1 and both monodentate and bidentate NO3‐. According to NMR spectroscopy this constitution seems to be maintained in solution. While the complexes 1 · ZnHal2 are insoluble, the complexes 2 · ZnHal2 and 2 · Zn(NO3)2 can be shown by NMR to undergo an equilibration in solution involving the LZn2+ and L2Zn2+ species of which only the LZn2+ species crystallizes as LZnX2. The zinc salts Zn(ClO4)2 and Zn(BF4)2 with noncoordinating anions react with 1 and 2 to form exclusively the L2Zn2+ complexes whose highly symmetrical octahedral geometry was ascertained for (1)2Zn(ClO4)2 by an X‐ray structure analysis.
Elektronenüberschuß‐Komplexe von Cobalt und Nickel mit Cyclobutadien‐Liganden: Synthese, Cyclovoltammetrie und Reaktivität
Authors: Herberich Gerhard E. , Klein Wolfram , Kölle Ulrich , Spiliotis Demetre 
Published: July 2007

Electron‐Excess Complexes of Cobalt and Nickel with Cyclobutadiene Ligands: Syntheses, Cyclovoltammetry, and Reactivity[1]A cyclovoltammetric investigation of tetraphenylcyclobutadiene complexes [ML(C4Ph4)]+ [1: ML = NiCp; 2a: ML = Co(C6H6); 2b: ML = Co(mesitylene)] reveals a reversible reduction to paramagnetic complexes 1 and 2a,b with a 19‐electron count, and a subsequent irreversible reduction to anions 1‐ and 2a,b‐ with a 20‐electron shell. Preparative reduction by one equivalent of CpFe(HMB) (HMB = C6Me6) produces the novel 19‐electron complexes 1 and 2b. Complex 1 can also be obtained by treatment of 1 · Br with one equivalent of CoCp2 at room temperature while reduction at ‐20°C with two equivalents of CoCp2 affords a novel C–C‐linked adduct CpNi[μ,η3:η4‐(C4Ph4–C5H5)]CoCp (5). Above ‐10°C a slow equilibrium between 5 and its components 1 and CoCp2 is observed with ΔH = 15 kJ/mol for the dissociation process. With an excess of the stronger reductant sodium amalgam the cations 1+ and 2a+ are reduced to give cyclobutenyl complexes ML(η3‐1,2,3,endo‐4‐C4HPh4) [6: ML = NiCp; 7: ML = Co(C6H6)]. 1 reacts with p‐nitrobenzyl bromide to give 1 Br and a p‐nitrobenzyl addition product CpNi[η3‐exo‐4‐(p‐O2NC6H4CH2)‐1,2,3,endo‐4‐C4Ph4] (11) while 2b reacts with MeI to give 2b · I and two isomeric methyl addition products (η5‐1,3,5,exo‐6‐C6H3Me4)Co(C4Ph4)] (12) and (mes)Co(η3‐exo‐4‐Me‐1,2,3,endo‐4‐C4Ph4) (13). Sodium‐amalgam reduction of the tetramethylcyclobutadiene cations [(arene)Co(C4Me4)]+ (4a: arene = C6H6; 4b: arene = mesitylene) affords diamagnetic dinuclear compounds of type 8–10 with C–C linkages between C4Me4/C4Me4, arene/C4Me4, and arene/arene rings, respectively.
Organotin cations stabilized by π coordination – synthesis and NMR studies in solution and in the solid state
Authors: Wrackmeyer Bernd , Kehr Gerald , Sebald Angelika , Kümmerlen Jörg 
Published: July 2007

AbstractThe organoboration of tetraalkynyltin compounds [Sn‐(CCR1)4 (1): R1 = Me (a), Et (b), Pr (c), iPr (d), tBu (e)] with triethylborane (2) proceeds stepwise. Intermediates with a cationic triorganotin (3, 5) and a dicationic diorganotin fragment (4), stabilized by intramolecular coordination of one and two alkynyl moieties, respectively, were isolated (3e, 4a) and/or identified by multinuclear NMR in solution (1H, 11B, 13C, 119Sn) and in the solid state (13C and 119Sn CP/MAS) (3e, 4a). The magnitude of 1J(13C13C) in 4a (101.0 Hz) is significantly smaller than that for sodium triethyl‐1‐propynylborate (7) (119.2 Hz), proving the weak coordination of the CC bond to the dicationic tin fragment. The final products of the organoboration, 1,4,6,9‐tetraalkyl‐2,7‐bis(diethylboryl)‐3,8‐diethyl‐5‐stannaspiro[4.4]nona‐1,3,6,8‐tetraenes (6b–6e) were obtained in high yield.
Koordinationschemie perhalogenierter Cyclopentadiene und Alkine, X[1] Darstellung und Molekülstruktur eines Cyclopentadienyl‐1,3‐dithiol‐π‐Komplexes, [C5Cl3(SH)2]Mn(CO)3
Authors: Sünkel Karlheinz , Blum Adrian 
Published: July 2007

Coordination Chemistry of Perhalogenated Cyclopentadienes and Alkynes, X[1]. – Synthesis and Molecular Structure of a Cyclopentadienyl‐1,3‐dithiol π Complex, [C5Cl3(SH)2]Mn(CO)3The reaction of [C5Cl4Li]Mn(CO)3 with elemental sulfur leads to [C5Cl4SLi]Mn(CO)3 (1), which is easily oxidized by air to the disulfide (OC)3Mn[C5Cl4S–SCl4C5]Mn(CO)3 (2). Addition of one equivalent of BuLi, followed by an excess of S8 produces the dithiolate [C5Cl3(SLi)2]Mn(CO)3 (3), which yields the dithiol [C5Cl3(SH)2]Mn(CO)3 (5) upon hydrolysis. The molecular structures of 2 and 5 have been determined by X‐ray diffraction.
Zur Darstellung von Nonafluorbutansulfonsäureestern
Authors: Frasch Markus , Sundermeyer Wolfgang , Waldi Joachim 
Published: July 2007

Preparation of Esters of Nonafluorobutanesulfonic AcidA series of new alkyl (2a–e), silyl (6a–1), germyl (7) and stannyl esters (8a, b) of nonafluorobutanesulfonic acid has been prepared by different methods (A–I) e.g. C4F9SO2OR [R = Me,Et, CH2CF3, CH2CCl3, CF3, GeMe3, SnMe3, SnEt3] and C4F9SO2OSiR3 [R = Me, Et, iPr, Bu, H, F, Cl, Ph, Ph2Me, PhMe2, Cl2Me]. These compounds are useful and extremely powerful alkylating or silylating reagents.
Diels‐Alder‐Reaktionen des Cyclobuta[1,2:3,4]dicycloheptatetraens, eines [4]Radialens
Authors: Hashmi Stephen , Szeimies Günter 
Published: July 2007

Diels‐Alder Reactions of Cyclobuta[1,2:3,4]dicycloheptatetraene, a [4]Radialene[4]Radialene 1 selectively adds active dienophiles like tetracyanoethylene, dimethyl acetylenedicarboxylate, 4‐phenyl‐1,2,4‐triazoline‐3,5‐dione, N‐phenylmaleimide, maleic anhydride, and benzyne at C‐1 and C‐10 to give Diels‐Alder adducts of type 6.
Polar Effects in Halogen Abstraction Reactions of Alkyl Radicals
Authors: Giese Bernd , Hartung Jens 
Published: July 2007

AbstractIn a series of structurally similar alkyl radicals 1a–c the tertiary 1,1‐dimethyl‐5‐hexenyl radical 1c reacts 30 times faster with carbon tetrachloride than the primary 5‐hexenyl radical 1a. The reactivity of the secondary 1‐methyl‐5‐hexenyl radical 1b aligns itself in between the primary and the tertiary radical 1a and 1c. The results indicate that the increasing nucleophilicity of the alkyl radicals is the major factor contributing to the reactivity.
Regiospezifische Insertion von Phenylacetylen in die ZrP‐Bindung von Cp2Zr{P(SiMe3)2}(Cl) und Folgereaktionen des Insertionsprodukts (Z)‐Cp2Zr{C(Ph)  C(H)P(SiMe3)2}(Cl)
Authors: Hey‐Hawkins Evamarie , Lindenberg Frank 
Published: July 2007

Regiospecific Insertion of Phenylacetylene into the ZrP bond of Cp2Zr{P(SiMe3)2}(Cl) and Derivatives of the Insertion Product (Z)‐Cp2Zr{C(Ph)  C(H)P(SiMe3)2}(Cl)The reaction of Cp2Zr{P(SiMe3)2}(Cl) (1) with phenylacetylene in boiling toluene yields regiospecifically the insertion product (Z)‐Cp2Zr{C(Ph)  C(H)P(SiMe3)2}(Cl) (2) which reacts with MeLi or nBuLi by forming the corresponding alkyl‐substituted zirconocene derivatives (Z)‐Cp2Zr{C(Ph)  C(H)P(SiMe3)2}(R) [R  Me (3), nBu (4)]. The attempt to prepare the C(Ph)  C(H)P(SiMe3)2− ligand directly from Li(THF)2P(SiMe3)2 and phenylacetylene yields HP(SiMe3)2 and LiCCPh. An X‐ray structure determination of 2 and 3 was carried out.
Makrobicyclische Endorezeptoren: Synthese, Kristallstruktur und Einschluß organischer Gastmoleküle
Authors: Lüer Ingo , Rissanen Kari , Vögtle Fritz 
Published: July 2007

Macrobicyclic Endoreceptors: Synthesis, Crystal Structure, and Inclusion of Organic GuestsThe macrobicyclic ligand 2 is synthesized in a one‐step cyclization procedure. According to an X‐ray structure analysis three dichloromethane guest molecules are included inside the cavity, whereas water and methanol are found outside the cavity. The rigid endo preorganization of the nitrogen donors allows the complexation of three 2,9‐disubstituted 1,10‐phenanthrolines inside the cavity.