bluuebunny/crossref_metadata_2025_split huggingface dataset:
1,3‐Diethoxy‐2‐azaindenylium‐hexachloroantimonat – ein destabilisiertes, cyclisches 1,3‐Dialkoxy‐2‐azaallyl‐Kation
Authors: Funke Wolfgang , Würthwein Ernst‐Ulrich 
Published: July 2007

1,3‐Diethoxy‐2‐azaindenylium Hexachloroantimonate – a Destabilized, Cyclic 1,3‐Dialkoxy‐2‐azaallyl CationRegioselective alkylation at the carbonyl oxygen atom of 3‐ethoxyisoindolenone (3) by using a triethyloxonium salt yields the title salt 4, a new anti‐Hückel‐aromatic compound. The isomeric N‐acyliminium salt 5 is not observed. 13C‐ and 14N‐NMR‐spectroscopic methods indicate unusual charge distribution in the five‐membered ring of 4; on the basis of AM1 calculations, this is attributed to ring strain exerted on the 2‐azaallyl moiety. Antiaromatic π‐interactions in this formally 8π‐electron system are minimized by lengthening of the benzylic bonds, as indicated by AM1 data.
Enthalogenierung und regioselektive Phosphiniden‐Fragmentierung unsymmetrisch substituierter Methylenbisphosphane RXP–CH2–PXR′ mit Fe2(CO)9
Authors: Adelt Stephan , Bitterer Frank , Fischer Jörg , Rothe Jürgen , Stelzer Othmar , Sheldrick William S. 
Published: July 2007

Dehalogenation and Regioselective Phosphinidene Fragmentation of Unsymmetrically Substituted Methylenebisphosphanes RXP‐CH2‐PXR′ with Fe2(CO)9Reductive dehalogenation of the unsymmetrically substituted methylenebisphosphanes RXP–CH2‐PR′X [X = Cl, Br; R = tBu, NEt2; R′ = 2,4,6‐R”3C6H2 (R” = Me, tBu), NEt2, 2,6‐iPr2C6‐H3O, 2,6,4‐tBu2MeC6H2O] with Fe2(CO)9 affords, depending on the reaction conditions employed, phosphido complexes [μ2‐(RP‐CH2‐PR′)]Fe2(CO)6 (2) or phosphaalkene clusters (μ3‐PR′)(η2,μ3‐PRCH2)Fe3(CO)9(6) or [(μ‐PR)(η2,μ3PR′CH2)]Fe3‐(CO)9 (7), respectively, by regioselective phosphinidene fragmentation of the RP–CH2‐PR′ skeletons. The unstable cluster compounds [μ3‐PR′–CH2–PR)]Fe3(CO)9 (4) are formed as intermediate products. X‐ray structural analysis of 6c (R = tBu; R′ = NEt2) reveals a flat butterfly (μ3‐PR)Fe3 structure bridged by the phosphaalkene ligand tBuP = CH2 with a short P = C distance [177.2(4) pm].
Zur Existenz zwitterionischer λ5‐(Ammonioorganyl)tetrafluorosilicate: Synthese sowie Kristall‐ und Molekülstruktur von Tetrafluoro(pyrrolidiniomethyl)silicat
Authors: Tacke Reinhold , Becht Joachim , Mattern Günter , Kuhs Werner F. 
Published: July 2007

On the Existence of Zwitterionic λ5‐(Ammonioorganyl)tetrafluorosilicates: Synthesis and Crystal and Molecular Structure of Tetrafluoro(pyrrolidiniomethyl)silicateThe zwitterionic tetrafluoro(pyrrolidiniomethyl)silicate (6) was synthesized by the reaction of trimethoxy(pyrrolidinomethyl)silane (7) with hydrogen fluoride in ethanol/hydro‐fluoric acid (yield 83%). 6 crystallizes in the space group P1/c with two crystallographically distinct molecules in the asymmetric unit. In both molecules the pentacoordinate silicon atom is surrounded by four fluorine atoms and one carbon atom, the latter being in an equatorial position. The coordination polyhedron of the silicon atoms can be described as a slightly distorted trigonal bipyramid. The zwitterionic structure was also proved for dissolved 6 (solution in CD3CN, NMR‐spectroscopic studies).
1,3‐Addition von Aziden an Azadecaboran: 6‐Azadecaboran‐4,9‐diyltriazene
Authors: Meyer Franc , Paetzold Peter , Englert Ulli 
Published: July 2007

1,3‐Addition of Azides to Azadecaborane: 6‐Azadecaborane‐4,9‐diyltriazenesnido‐NB9H12 (1) reacts with azides RN3 to form a coordinative B–N bond between B9 and N1 of RN3, accompanied by the α‐addition of the B4–H bond of 1 to the N3 atom of RN3. The products 2a, b (R = H, CH2Ph, respectively) thus contain an azadecaborane skeleton and a five‐membered unsaturated B2N3 ring with a common B–B edge. The product 2a crystallizes in the space group Pna21.
(E,Z)‐Gleichgewichte, 15. Synthesen und erhöhte Konfigurationslabilität von 2‐Iminoindan‐Derivaten mit Vorderseitenspannung
Authors: Knorr Rudolf , Ferchland Kathrin , Mehlstäubl Johann , Hoang Thi Phung , Böhrer Petra , Lüdemann Hans‐Dietrich , Lang Elmar 
Published: July 2007

(E,Z) Equilibria, 15[1]. – Syntheses and Lability of the Configuration of 2‐Iminoindan Derivatives with Front StrainSyntheses and properties are described for sterically shielded imines R2C = NR (3c, e, g–k), which are rather inert toward nucleophiles. Nucleophilic attack at the nitrogen atom of 3k is indicated by the formation of the azine 4. (E,Z) Configurational diastereotopomerization (anti/syn) is strongly dependent on N substituents [CH3, phenyl, 1‐naphthyl, acetyl, Si(CH3)3, cyano, SC6H5, SOC6H5, SO2C6H5, and nitro]. It is accelerated by front strain along the CN bond in 3a–c, e, g, h, j, and k and provides an energetic basis (by ΔG≠ and ΔΔG≠ values) for the gauging of force‐field parameters. This (E,Z) stereo‐mutation is characterized by a vanishing solvent dependence and a positive volume of activation (+10.2 cm3 mol‐1 for 3a). In contrast to other π acceptor substituents, the N‐nitro group in 31 retards (E,Z) interconversion.
Synthese und optische Eigenschaften endständig substituierter konjugierter Polyene mit Bicyclo[2.2.2]octan als Spacer
Authors: Effenberger Franz , Kesmarszky Thomas 
Published: July 2007

Synthesis and Optical Properties of Terminally Substituted Conjugated Polyenes with Bicyclo[2.2.2]octane as SpacerThe conjugated polyenes 10, 11, and 17 respectively, with 9‐anthryl‐ and 2‐tetraphenylporphyrinyl (TPP) terminal groups and a bicyclooctane unit incorporated into the polyene chain were synthesized by Wittig olefinations. In all cases it was possible to obtain the all‐(E) compounds from the (E)/(Z)‐isomeric mixtures by chromatographic purification and several recrystallizations. From the UV/Vis spectra the separation of the TPP group and the polyene chain in 10, 11, and 17 can be deduced whereas in 10 and 11 the two conjugated double bonds are amalgamated into the anthryl group. In 17 the anthryl group is electronically separated from the polyene chain, and a selective excitation therefore is possible.
Organometall‐Imide – Höhervalente Derivate der d‐Metall‐Säure, 2. Alkyl‐, Aryl‐ und Cyclopentadienyl‐substituierte Molybdän(VI)‐ und Wolfram(VI)‐Imide
Authors: Radius Udo , Sundermeyer Jörg 
Published: July 2007

Organometallic Imido Complexes – Highervalent Derivatives of the d‐Metal Acids, 2[4]. – Alkyl‐, Aryl‐, and Cyclopentadienyl‐Substituted Molybdenum(VI) and Tungsten(VI) Imido ComplexesCpMo(NtBu)2Cl (1a) and CpW(NtBu)2Cl (1b) (Cp = η5‐C5H5) react with organolithium reagents to form alkyl and aryl complexes of the type CpMo(NtBu)2R 2a–4a and CpW(NtBu)2R 2b–4b, resp., (R = Me, CH2SiMe3, Ph), highly volatile organo‐metallic compounds, which were isolated as analytically and spectroscopically pure oils by vacuum destillation. On the other hand, the protolysis reaction of 1a and 1b with excess of HCl gas affords monoimido complexes CpMo(NtBu)Cl3 (5a) and CpW(NtBu)Cl3 (5b), respectively.
Mixed amide thiolate complexes of zinc with low coordination number at the metal atom
Authors: Grützmacher Hansjörg , Steiner Matthias , Pritzkow Hans , Zsolnai Laszlo , Huttner Gottfried , Sebald Angelika 
Published: July 2007

AbstractThree different thiophenoles 2,4,6‐(CF3)3C6H2SH (4), 2,4,6‐(iPr)3C6H2SH (5), and 2,6‐(Me3Si)2C6H3SH (6) with bulky sub‐stituents in ortho position were treated with Zn[N(SiMe3)2]2 (7) in a non‐coordinating solvent like CH2Cl2 or toluene to yield mixed amide thiolate zinc complexes Zn2[N(SiMe3)2]{S[2,4,6‐(CF)3C6H2]}3 (8), Zn3[N(SiMe3)2]2{S[2,4,6‐(iPr)3C6H2]}4 (9), and Zn2{S[2,6‐(Me3Si)2C6H3]}4 (10), respectively. These compounds comprise low‐coordinated zinc atoms. Initially, the reactions were performed in a 1:1 ratio of the reactants. However, in no reaction the expected {Zn[N(SiMe3)2](SR)}x (X = 1,2,3…) species were obtained but compounds which are richer in thiolate substituents (SR/NR2 > 1) even if a large excess of amide 7 was used. Distinct from these, the reaction between 7 and 2,6‐(iPr)2C6H3OH (14) in a 1:1 ratio afforded indeed dimer Zn2[N(SiMe3)2]2{O[2,6‐(iPr)2C6H3]}2 (15). The molecular structures of 8, 9, 10, and 15 in the crystal are elucidated by X‐ray structural analyses and compared with proposed structures in solution based on multinuclear NMR experiments.
Photoinduced electron transfer in porphyrin‐quinone cyclophanes, 6. Porphyrin‐quinone cyclophanes with gradually varied acceptor strength: Syntheses and characterizations
Authors: Staab Heinz A. , Weiser Jürgen , Futscher Michael , Voit Guido , Rückemann Andreas , Anders Christine 
Published: July 2007

AbstractFor studying intramolecular electron‐transfer reactions, three groups of double‐ and single‐bridged porphyrin‐quinone cyclophanes 1–4, 5–9, and 11–14, resp., with gradual variation of quinone acceptor strengths were synthesized. As key intermediates for building up the porphyrin‐cyclophane skeleton the correspondingly 3,6‐substituted 1,4‐bis[4‐(2‐formylphenyl)‐butyl]‐2,5‐dimethoxybenzenes 15–20 were synthesized. Condensation with pyrrole yielded the doubly bridged porphyrin cyclophanes 42–45; via the bis(dipyrrolylmethyl) derivatives 46–51 and 64–67 the single‐bridged porphyrin cyclophanes 58–63 and 72–75 were obtained by acidic condensation with triethyl formate. Cleavage of the methoxy groups and oxidation yielded the corresponding porphyrin‐quinone systems. Some magnesium and zinc complexes of these cyclophanes are described. Spectroscopic data (MS, 1H NMR) are reported in support of the proposed structures.
Siderophore, II. Tetrazolylenolat‐ und Semicorrinat‐Anionen als Chelatliganden für Eisen(II)‐und Kupfer(II)‐Ionen: Vom Molekül zum Kollektiv. Siderophores, II[1]. – Tetrazolyl Enolate and Semicorrinate Anions as Chelate Ligands for Iron(II) and Copper(II) Ion: From Molecular to Collective Structures
Authors: Saalfrank Rolf W. , Struck Oliver , Nunn Kurt , Lurz Claus‐Jürgen , Harbig Roland , Peters Karl , Schnering Hans Georg Von , Bill Eckhard , Trautweinc Alfred X. 
Published: July 2007

AbstractReaction of tetrazolyl enolate 2 (HL2) with Cu(II) acetate yields the 3D‐coordination polymer 4 ([CuL22]n). the structure of which is unequivocally established by single‐crystal X‐ray diffraction. The formation of 4 is understandable if 2 or its enolate is considered as tridentate chelate ligand and if an intermediate formation of the coordinatively unsaturated copper(II) building block 6 is assumed. The monomers 6 are bidentate coordinating by the two CN groups, which leads to linking of monomers and to coordinative saturation at the copper(II) center of 6 with formation of three‐dimensional 4. Semicorrin 8 (HL4), however, reacts with Fe(II) to give the exceptional mononuclear tetrahedral chelate complex 10 (X‐ray). EPR and Mössbauer spectra of 4 and 10 are discussed.
Phosphane – Tetrahalodiborane(4) Adducts: Formation of closo‐3,4,5,6‐Tetrabromo‐1,2‐diphosphahexaborane(4)
Authors: Keller Willi , Sneddon Larry G. , Einholz Wolfgang , Gemmler Armin 
Published: July 2007

AbstractTetrabromodiborane(4), B2Br4, forms a 1:2 adduct 1 with PBr3, which reacts at 350°C to closo‐1,2‐P2B4Br4 (4a) in 25% yield. Compound 4a neither rearranges to the 1,6‐isomer nor decomposes to an appreciable extent upon heating to 650°C. B2C14 reacts with equimolar amounts of either tris(trimethylsilyl)‐phosphane or 1,2‐bis(dichlorophosphanyl)ethane to give B2Cl4 · P(SiMe3)3 (2) and B2Cl4 · Cl2PCH2CH2PCl2 (3), respectively. Compound 2 represents the first phosphane – diborane(4) monoadduct with two boron atoms in different coordination environment.
Lanthanoiden‐Komplexe, II. Tris(tert‐butylcyclopentadienyl)neodym, ‐dysprosium und ‐thulium. Kristall‐ und Molekülstruktur von Bis(tert‐butylcyclopentadienyl)‐hydroxidoneodym und ‐dysprosium
Authors: Herrmann Wolfgang A. , Anwander Reiner , Kleine Matthias , Öfele Karl , Riede Jürgen , Scherer Wolfgang 
Published: July 2007

AbstractComplexes of the Lanthanides, II[1]. – Tris(tert‐butylcyclopentadienyl)neodymium, ‐dysprosium, and ‐thulium. Crystal and Molecular Structure of Bis(tert‐butylcyclopentadienyl)hydroxidoneodymium and ‐dysprosiumNdCl3, DyCl3, and TmI3 (1a–c) react with the potassium salt K(tBuCp) (2) of tert‐butylcyclopentadiene in THF to yield the sublimable homoleptic tris(tert‐butylcyclopentadienyl) complexes of formula Ln(tBuCp)3 (3a–c). The thermal behavior makes these compounds potential precursors for chemical vapour deposition techniques (MOCVD).
Lanthanoiden‐Komplexe, III. Flüchtige Neodym‐ und Yttrium‐Alkoxide mit neuen sperrigen Chelatliganden
Authors: Herrmann Wolfgang A. , Anwander Reiner , Denk Michael 
Published: July 2007

AbstractComplexes of the Lanthanides, III[1]. – Volatile Neodymium and Yttrium Alkoxides with New Bulky Chelating LigandsThe synthesis of a new type of lanthanide alkoxides is described. The “clinching alcohols” HOCHtBuCH2OEt (1a), HOCHtBuCH2NEt2 (1b), HOCtBu2CH2OEt (1c), and HOCH‐i Pr2CH2OEt (1d) react with Nd[N{Si(CH3)3}2]3 (2a) to form the corresponding homoleptic alkoxide complexes 3a–d. The same procedure is applied to obtain the novel yttrium alkoxide 4 from the amide precursor 2b and the alcohol 1d. The new complexes are all very soluble in aliphatic hydrocarbons and were characterized by means of analyses and spectroscopy. The interesting property of these complexes is their remarkable volatility, the highest so far achieved for lanthanide alkoxides.
Two‐Photon Chemistry in the Laser Jet: Photochemistry of the Diphenylhydroxymethyl Radical
Authors: Adam Waldemar , Oestrich Rolf Schulte 
Published: July 2007

AbstractIn the laser‐jet mode (argon ion laser) the excited hydroxy‐diphenylmethyl radical (3*) underwent H expulsion in inert solvents (benzene, acetonitrile) to produce benzophenone (two‐photon product), besides dimerization of its ground state 3 to benzpinacol (one‐photon product). In ethanol, the laser‐jet photolysis of benzophenone afforded as new products (two‐photon chemistry) benzhydrol, 4‐(1‐hydroxyethyl)benzophen‐one (1), together with benzpinacol and 1,1‐diphenyl‐1,2‐propandiol (4), which are also observed in low‐intensity photolyses (one‐photon chemistry). Benzhydrol is formed through H abstraction from the excited radical 3* and ketone 1 possibly by coupling of an excited radical 3* at its para position (highest spin density) with a transient 1‐hydroxyethyl radical. Photolysis of α‐phenylbenzoin (2) produced benzpinacol, benzophenone, pinacol 4, benzhydrol, ketone 1, and the benzoyl‐derived products benzil and benzaldehyde. Also benzhydrol was observed as a two‐photon product.
1,1,3,3‐Tetraalkoxy‐2‐azaallylium‐Salze: Darstellung und stereochemische Eigenschaften
Authors: Kupfer Rainer , Meier Stefan , Würthwein Ernst‐Ulrich 
Published: July 2007

Abstract1,1,3,3‐Tetraalkoxy‐2‐azaallylium Salts: Synthesis and Stereochemical Properties The title salts 1 were synthesized in satisfactory yield by regioselective alkylation at the carboxyl oxygen atom of N‐(dialkoxymethylene)carbamates 7 with oxonium salts 8. According to IR, 1H‐ and 13C‐NMR spectra, in solution a bent 2‐azaallyl cation structure is strongly favored over a linear cumulenic form. Dynamic NMR spectra indicate a barrier of ca. 11.7 kcal/mol between these two valence isomers. – Quantum mechanical calculations (ab initio 3–21G optimizations) on the model compound 1,1,3,3‐tetrahydroxy‐2‐azaallylium (9) confirm the 2‐azaallyl structure as the global minimum on the energy hyperface. 2‐Azaallenium structures are calculated to be ca. 20 kcal/mol higher in energy. The conformations of the hydroxy groups depend on the C – N – C bond angle. The best isomeric N‐protonated N‐(dialkoxymethylene)carbamate 10a is predicted to be favored by ca. 3 kcal/mol over the energy lowest 2‐azaallylium structure 9a.
Neue Untersuchungen zur Reaktivität von Formaldehyd‐O‐oxid, Acetaldehyd‐O‐oxid und Propionaldehyd‐O‐oxid
Authors: Reiser Ralf , Süling Carsten , Schröder Gerhard 
Published: July 2007

AbstractNew Studies Concerning the Reactivity of Formaldehyde Oxide, Acetaldehyde Oxide, and Propionaldehyde OxideReactivity and selectivity of formaldehyde oxide (1a), acetaldehyde oxide (1b), and propionaldehyde oxide (1c) is tested by adding a cooled solution of one or two dipolarophiles to a solution of the primary ozonides of the olefins 2a, 2b or the ketene acetals 7a–c, respectively. Different selectivities are observed for the different carbonyl oxides. Only 1a is able to react with non‐activated olefins like methylenecyclopentane (4a), norbornene (4b), 3‐methylstyrene (4c), and cyclopentadiene (4d) under these conditions. Activated olefins turn out to be good quenchers for 1a. Both 1a and 1b react with fulvene 4e in completely different ways. Contrary to 1a, the carbonyl oxides 1b and 1c clearly prefer carbonyl compounds to activated olefins.
Tricarbonylchrom‐Komplexe von chiralen [2.2]Metacyclophanen: Darstellung, Struktur und chiroptische Eigenschaften
Authors: Schulz Jürgen , Bartram Stefan , Nieger Martin , Vögtle Fritz 
Published: July 2007

AbstractTricarbonylchromium Complexes of Chiral [2.2]Metacyclophanes: Syntheses, Structures, and Chiroptical PropertiesHPLC‐baseline separations of three racemic cyclophanes 3, 4, and 6 on cellulose tris(3,5‐dimethylphenyl)carbamate led to their enantiomers with high optical purity. Complexation of (‐)‐3 and (+)‐3 with triamminetricarbonylchromium yielded chiral Cr(CO)3 complexes (‐)‐(S)P‐(3S)M‐3a and (+)‐(R)P‐(3R)M‐3a stereoselectively. Derivatisation of the complexes by lithiation and reaction with electrophiles gave new substituted chiral Cr(CO)3 complexes of [2.2]metacyclophanes regio‐selectively. X‐ray structure analyses of one chiral chromium complex (‐)‐(R)P‐(5S)M‐14a and three chiral chromium‐free ligands (‐)‐(S)P‐3, (‐)‐(S)P‐4, and (‐)‐(S)P‐6 led to the assignment of the absolute configurations of all chiral compounds discussed here. The influences of substituents on the chiroptical properties are investigated. The helicity of [2.2]metacyclophanes is discussed. For the first time X‐ray structure analyses were performed of a bis‐Cr(CO)3 complex (9a) as well as of the first chromium complex 10a of a heteraphane. Dethioketalisation of (‐)‐(S)P‐3 with NBS gave (‐)‐(S)P‐18, the absolute chirality of which has been known, under retention of configuration.
Reversible [4 + 1]‐Selbstaddition von Alkyl(arylimino)phosphanen und regioselektive Cycloaddition mit (E)‐ und (Z)‐Azobenzol
Authors: Niecke Edgar , Link Manfred , Nieger Martin 
Published: July 2007

Reversible [4 + 1] Selfaddition of Alkyl(arylimino)phosphanes and Regioselective Cycloaddition to (E)‐ and (Z)‐AzobenzeneDehydrohalogenation of the amino(chloro)phosphanes RP(Cl)N(H)Aryl (1; RMe, Et; Aryl = 2,4,6‐Tri‐tert‐butylphenyl) affords the corresponding iminophosphanes RP NAryl (2) which undergo a reversible [4 + 1] selfaddition with participation of the aryl substituent to form 3,3a‐Dihydro‐2H‐1,2,3λ5‐benzoazadiphospholes 3. The regioselective cycloaddition of 2b towards (E)‐ and (Z)‐azobenzene (4a and b) has been demonstrated in the formation of two different phospholes 6 and 8 which are formed by a [2 + 1] and [4 + 1] cycloaddition reaction of the iminophosphane 2b. The structure of the fiveymembered ring systems 3, 6 and 8 has been elucidated by NMR spectroscopy and single‐crystal X‐ray studies of 3b and 6.
1,2,3,4–Diazadiboretidine: Reaktionen einer neuen Klasse ungesättigter Bor–Stickstoff–Vierringe
Authors: Thiele Björn , Paetzold Peter , Englert Ulli 
Published: July 2007

1,2,3,4–Diazadiboretidines: Reactions of a Novel Class of Unsaturated Boron–Nitrogen Four–Membered Rings1,2,3,4–Diazadiboretidines [B(tBu)–B(tBu)NR–NR] (REt, iPr: 2a, b) belong to the hitherto unknown class of head–head isomers of the known 1,3,2,4–diazadiboretidines (1). They are formed from the diborane(4) Cl–B(tBu)–B(tBu)–Cl and the hydrazines RHN–NHR in the presence of NEt3 via the partially unsaturated four–membered rings [–B(tBu)Cl–B(tBu)NR–NHR–] (4a, b), which are transformed into 2a, b by the abstraction of HCl by means of the base LiNC9H18. Whereas the pure products 2a, b are instable, solutions of 2a, b in alkanes can be handled at 0°C without considerable decomposition. Reaction of 2a, b with the amine oxide Me3NO leads to insertion of an O atom, reaction with diazoalkane tBuCR′N2 (R′  H, Me) to insertion of its β–N atom, and reaction with the azide PhCH2N3 to insertion of a nitrene N atom into the B–B bond of 2a, b with formation of five–membered rings 5a, b or 6a, b or 7a, b, respectively. Six–membered rings 8a, 9a, 10a, respectively, are the products of the insertion of the CC unit of 3–hexyne, the NN unit of EtO2C–NN–CO2Et, or the unsaturated C atoms of two molecules of CNtBu into the B–B bond of 2a. The condensation of the diaminodiborane(4) Cl–B(NMe2)–B(NMe2)–Cl with the hydrazine EtHN–NHEt in the presence of NEt3 yields the corresponding eight–membered ring [–B(NMe2)–B(NMe2)–NEt–NEt–]2 (11), which crystallizes in a twist conformation with symmetry group D2.
Beiträge zur Chemie des Bors, 213. Reaktionen eines Amino–imino–borans mit Triboran(7) und Decaboran(14)
Authors: Geisberger Gilbert , Linti Gerald , Nöth Heinrich 
Published: July 2007

Contributions to the Chemistry of Boron, 213[1]. – Reactions of an Amino–imino–borane with Triborane(7) and Decaborane(14)Triborane(7)‐THF hydroborates (tert‐butylimino)(tetramethylpiperidino)borane 1 slowly to form μ‐(tert‐butylamino)‐μ‐(tetramethylpiperidino)tetraborane(8) 5. This molecule shows fluxional behaviour at ambient temperature in solution. In the solid state, an X–ray structure analysis reveals the presence of the asymmetric 1104–styx valence tautomer. 1 does not react at ambient temperature with pentaborane(9) in dichloromethane/hexane solution. However, 1 reacts rapidly with decaborane(14) to produce a tetramethylpiperidine adduct of an 11‐(tert‐butylamino)undecaborane(14) as determined by an X–ray structure analysis. The same kind of reaction occurs between decaborane(14) and (2,6–diisopropylphenylimino)‐(2,2,6,6–tetramethylpiperidino)borane. Thus, decaborane(14) acts as a diprotic acid towards amino–imino–boranes.
Solid–State Structure of Tris(phenylsilyl)amine
Authors: Mitzel Norbert , Schier Annette , Schmidbaur Hubert 
Published: July 2007

AbstractThe solid–state structure of tris(phenylsilyl)amine (1) has been determined by single–crystal X–ray diffraction analysis. The compound crystallizes in the trigonal space group R3 with three formula units in the unit cell. The molecules, which display crystallographic C3 symmetry, contain almost completely planar NSi3 units with a propeller–like arrangement of the phenyl rings attached to them. By contrast, the carbon analogue tribenzylamine is strongly pyramidal at nitrogen, which – in the absence of steric effects – clearly demonstrates the planarization effect of silicon as a substituent to nitrogen in tertiary amines.
Dimethyldioxirane Oxidation of Enamines: First Spectral Evidence for Enamine Oxides by Stabilization through N‐Silylation
Authors: Adam Waldemar , Ahrweiler Michael , Paulini Klaus , Reißig Hans–Ulrich , Voerckel Volkmar 
Published: July 2007

AbstractThe oxygen transfer to the enamines 1a–f by dimethyldioxirane (DMD) in acetone solution leads to the α–amino epoxides 2a–f. The stability of the α–amino epoxides 2a–f depends only on the type of substitution at the nitrogen atom. Thus, while the epoxides 2a, b could be characterized spetroscopically, the epoxidation of the enamines 1c–f resulted in the corresponding α–amino ketone 3c (hydride shift) and the amides 4d–f (alkyl shift). The α‐[bis(trimethylsilyl)]amino epoxides 2a, b represent the first observable enamine oxides and emphasize the value of stabilizing such labile epoxides through disilylation of the enamine nitrogen atom.
Synthesis of Homobenzoctamine [9,10–Dihydro–9‐(1–methylaminomethyl)‐9,10–propanoanthracene] and Homomaprotiline [9,10–Dihydro–9‐(3–methylaminopropyl)‐9,10–propanoanthracene]
Authors: Karama Usama , Martin H. , Hoffmann R. 
Published: July 2007

AbstractThe synthesis of homobenzoctamine (10) and homomaprotiline (19) is described.