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  • 1970-1974  (30)
  • Chemistry  (30)
  • 27Al-NMR spectroscopy
  • Ab initio calculations
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  • 1
    Electronic Resource
    Electronic Resource
    Beiträge zur Chemie des Bors, LIV. Chemische Eigenschaften von Tris(2.2-dimethyl-hydrazino)-boran (1971)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 104 (1971), S. 549-557 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Boron, LIV. Chemical Properties of Tris(2.2-dimethylhydrazino)boraneIn contrast to the ready cleavage of BN-bonds in tris(dialkylamino)boranes by BCl3, (BH3)2, HCl or CH3J the prefered reactions of these acids with tris(2.2-dimethylhydrazino)borane (1) are additions. Due to the greater basicity of the dimethylamino group as compared to the NH moiety, additions occur at the group (CH3)2N before the group NH is attacked. Solvolysis of B[NH—N(CH3)2]3 (1) by H2O or C2H5OH yields (CH3)2 N—NH2 and B(OH)3 or B(OC2H5)3, respectively, but no mixed compounds XnB[NH—N(CH3)2]3 n are formed in these reactions or by ligand exchange with B(OCH3)3 or B[N(CH3)2]3. 1 is stable up to 280° at higher temperature condensation with formation of N.N-dimethylhydrazine occurs.
    Notes: Während die Verbindungen BCl3, (BH3)2, HCl und CH3J die B N-Bindungen von Tris(dialkylamino)-boranen spalten, lagern sie sich an Tris(2.2-dimethyl-hydrazino)-boran (1) an. Dabei erfolgt zunächst Addition an die stärker basische Dimethylaminogruppe, danach reagiert auch die schwächer basische NH-Gruppe. Solvolysen von 1 mit H2O und C2H5OH oder Komproportionierungen mit B(OCH3)3 oder B[N(CH3)2]3 führen nicht zu gemischten Verbindungen XnB[NH—N(CH3)2]3 n(X—OH, OR, N(CH3)2). Im Vergleich zu Tris(alkylamino)-boranen ist 1 thermisch sehr stabil. Erst oberhalb 280° spaltet sich N,N-Dimethylhydrazin ab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19711040225
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  • 2
    Electronic Resource
    Electronic Resource
    Beiträge zur Chemie des Bors, LV. Intramolekulare Wasserstoffbrückenbindungen in (2.2-Dimethyl-hydrazino)-boranen (1971)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 104 (1971), S. 558-576 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Boron, LV. Intramolecular Hydrogen Bonding in (2.2-Dimethylhydrazino)boranesN. m. r. spectroscopic investigations on (2.2-dimethylhydrazino)boranes demonstrate the presence of intramolecular hydrogen bonds in these compounds, and this is further proved by comparison with isopropylaminoboranes. The planar configuration of B[NH—N(CH3)2]3 and B2[NH—N(CH3)2]4 is determined by this bonding. The N—H … N bond energy has been estimated as ∼2.5 kcal/mole from the temperature dependence of the n. m. r. spectra. Intermolecular association is indicated in the compounds R2B—NH—N(CH3)2. - The basicity towards the acid CDCl3 decreases in the isopropylaminoborane series for (2.2-dimethylhydrazino)boranes the series has been found confirming the effects of intramolecular hydrogen bonding.
    Notes: Kernresonanzspektroskopische Untersuchungen an (2.2-Dimethyl-hydrazino)-boranen belegen durch Vergleich mit Isopropylamino-boranen intramolekulare Wasserstoffbrückenbindungen. Diese sind insbesondere für B[NH—N(CH3)2]3 und B2[NH—N(CH3)2]4 konfigurationsbestimmend. Ihre Bindungsenergie beträgt ∼2.5 kcal/Mol. In R2B—NH—N(CH3)2 erfolgt Assoziation über intermolekulare N—H … N-Bindungen, die in Lösung leicht aufbrechen. - Basizitätsbestimmungen mit der Referenzsäure CDCl3 ergeben die Reihe für die Isopropylamino-borane, jedoch für die (2.2-Dimethyl-hydrazino)-borane in Übereinstimmung mit den durch intramolekulare Wasserstoffbrückenbindungen bewirkten Effekten.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19711040226
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  • 3
    Electronic Resource
    Electronic Resource
    Beiträge zur Chemie des Bors, LVI. Derivate des Hydrazino-diphenylborans (1971)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 104 (1971), S. 722-733 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contribution to the Chemistry of Boron, LVI. Derivatives of HydrazinodiphenylboraneHydrazinodiphenylboranes of the type XNH—NH—B(C6H5)2 are monomeric (1a). The acyl derivatives (1b—d) (X = C6H5CO, CH3CO, (C6H5)2P(O)) are all internally coordinated through BO-bonds. -N.N′-Bis(diphenylboryl)derivatives of hydrazines (2a—c) are obtained from (C6H5)2BN(C2H5)2 and N2H4, CH3NH—NH2, or CH3NH—NHCH3 but no N.N′-bis-(diphenylboryl)hydrazines can be prepared by this method. Compounds of the latter type (3) are accessible via N-lithiohydrazines. - The structures of the new compounds are discussed and some of their chemical properties reported.
    Notes: Hydrazino-diphenylborane des Typs XNH—NH—B(C6H5)2 sind monomer (1a); in den N-Acyl-N′-diphenylboryl-hydrazinen (1b—d) (X = C6H5CO, CH3CO, (C6H5)2P(O)) liegt vierbindiges Bor vor. - N.N′-Bis-diphenylborylierung an Hydrazinen gelingt durch Einwirkung von (C6H5)2BN(C2H5)2 auf Hydrazin, Methylhydrazin und N.N′-Dimethyl-hydrazin (Bildung von 2a—c). Diese Umaminierung kann zur Darstellung von N.N′-Bis(diphenylboryl)-hydrazinen nicht herangezogen werden; sie (3) sind jedoch über mit LiCH3 metallierte Hydrazinderivate zugängig. - Die Strukturen der neuen Verbindungen werden diskutiert und einige ihrer chemischen Eigenschaften beschrieben.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19711040309
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  • 4
    Electronic Resource
    Electronic Resource
    Kernresonanzspektroskopische Untersuchungen an Bor-Verbindungen, V. 1lB- und 14N-Kernresonanzmessungen an Alkoxy-, Alkylthio- und 1-Pyrrolylboranen (1973)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 106 (1973), S. 1145-1164 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Nuclear Magnetic Resonance Studies on Boron Compounds, V. 11B and 14N N.M.R. Measurements of Alkoxy-, Alkylthio- and 1-Pyrrolylboranesδ11B and δ14N data for amino(alkoxy)- and amino(alkylthio)boranes as well as for a series of 1-pyrrolylboranes and related compounds are discussed. The δ14N data can be interpreted in terms of donation of the nitrogens free pair of electrons to the boron atoms as well as by the influence of inductive and steric effects, provided that only comparable series of compounds are discussed.
    Notes: Die chemischen Verschiebungen δ11B und δ14N für Amino(alkoxy)- und Amino(alkylthio)-borane sowie für eine Reihe von 1-Pyrrolylboranen und verwandten Verbindungen werden diskutiert. Die beobachteten δ14N-Werte erlauben Aussagen über die relative Beanspruchung des freien Elektronenpaares der Stickstoffatome durch das Boratom sowie über den Einfluß induktiver und sterischer Effekte bei vergleichbaren Verbindungsreihen.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19731060413
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  • 5
    Electronic Resource
    Electronic Resource
    Beiträge zur Chemie des Bors, LXII. N-Funktionelle Aminoborane : (Thiophosphorylamino)- und (Thiophosphinylamino)-diorganylboraneTeil der Staatsexamensarbeit D. Reiner, Univ. München 1972, und Teil der einzureichenden Dissertation W. Storch, Univ. München. (1973)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 106 (1973), S. 1508-1524 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Boron, LXII. N-Functional Substituted Aminohoranes : (Thiophosphorylamino)- and (Thiophosphinylamino)-diorgan ylboranesCompounds of the type R2P(S)—NR′—BR2″ (R=CH3, C6H5, (CH3)2N.—CH2(CH3N; R′ = CH3, C2H5, C6H5) are obtained a) by Si—N bond cleavage of R2P(S)—NR′—Si(CH3)3, b) by reaction of N-metallated thiophosphoryl- or thiophosphinylamines with diorganylboron halides, or c) by addition of sulfur to R2P—NR—BR2″. Si—N cleavage of silylamino-boranes by R2P(S)Cl predominantly yields borazines. As shown by n.m.r. investigations the barrier of rotation of the B—N bond decreased by introducing the R2P(S) group at the N atom of a monoaminoborane in accordance with the observed deshielding of the boron nucleus. This indicates a weakening at the B—N bond.
    Notes: Verbindungen des Typs R2P(S)—NR′—BR2″. (R=CH3, C6H5, (CH3)2N,—CH2(CH3)N; R′ = CH3, C2H5, C6H5) erhält man a) durch Silazanspaltung von R2P(S)—NR′—Si(CH3)3 und b) durch Umsetzung N-metallierter Thiophosphoryl- oder Thiophosphinylamine mit Diorganylborhalogeniden sowie c) durch Schwefeladdition an R2P—NR′—BR2″. Die Si—N-Spaltung von Silylaminoboranen durch R2P(S)Cl führt hingegen bevorzugt zu Borazinen. Wie die NMR-Spektren zeigen, senkt die Einführung der R2P(S)-Gruppe am N-Atom eines Aminoborans die Höhe der Rotationsbarriere um die B—N-Bindung in Übereinstimmnng mit dem beobachteten Abschirmungsverlust des B-Atoms. Dies zeigt eine Schwächung der B—N-Bindung an.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19731060517
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  • 6
    Electronic Resource
    Electronic Resource
    Beiträge zur Chemie des Bors, LXVII. Silaborazine aus Cyclosilazanen (1974)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 107 (1974), S. 3113-3120 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Boron, LXVII. Silaborazines from CyclosilazanesPhenyldichloroborane reacts with [(CH3)2SiNH]3 (5) to yield the disilaboranine 8, the monosilaborazine 7, and/or B,B′, B″-triphenylborazine (9), depending on the ratio of the reactants. Reaction with octamethylcyclotetrasilazane, [(CH3)2SiNH]4 (12), in a 1:1 molar ratio leads to NH4Cl, 8, and a polymer. Product analysis shows that only part of 8is formed by direct SiN-cleavage, the other part results from a substitution leading to NH4Cl.
    Notes: Phenylbordichlorid reagiert je nach Molverhältnis mit [(CH3)2SiNH]3 (5) zum Disilaborazin 8, Monosilaborazin 7und/oder B,B′, B″-Triphenylborazin (9). Bei der Umsetzung mit Octamethylcyclotetrasilazan, [(CH3)2SINH] 4 (12), im Molverhältnis 1:1 entstehen NH4Cl, 8 und Polymere. Aus der Stoffbilanz folgt, daß nur ein Teil von 8über direkte Silazanspaltung entstehen Kann; der andere ist die Folge einer zu NH4Cl führenden Substitutionsreaktion.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19741070932
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  • 7
    Electronic Resource
    Electronic Resource
    Kernresonanzspektroskopische Untersuchungen an Borverbindungen, VIII. Vergleichende Betrachtungen von 11B- und 14N-Kernresonanzdaten dreifach Koordinierte Bor-Verbindungen mit 13C- und 14N-Kernresonanzdaten von Carbonsäure-derivaten und Carbonium-Ionen (1974)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 107 (1974), S. 3089-3103 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Nuclear Magnetic Resonance Studies on Boron Compounds, VIII Comparison of 11B and 14N N.M.R. Data of Tervalent Boron Compounds with 13C and 14N N.M.R. Data of Derivatives of Carbonic Acids and Carbonium IonsThe δ14N data of N-methylureas, -carbamates, -acetamide, and -diacetamide correlate linearly with the δ δ14N data of the isosteric aminoboranes B[N(CH3)2]3, (CH3B[N((CH3)2]2, and (CH3)2-BN(CH3)2. The same is true for the series of the guanidinium, amidinium, and imonium ions and the corresponding isoelectronic aminoboranes. A comparison of δ13C and δ11B n.m.r. chemical shifts for the first series of compounds only shows a trend towards low field shift as the positive charge at the respective atoms increases. However, in the case of carbonium ions and isoelectronic boranes there is a linear relationship between δ 13C and δ11B, as given by the equation δ 11B = 0.393 δ 13C - 30.73. From the data δ 11B = -70.0 ppm is deduced for monomeric BH3.
    Notes: Die δ14N-Werte von N-Methyliertem Harnstoff, Carbamidsäureester, Acetamid und Diacetamid stehen mit den δ14N-Daten der isosteren Aminoborane B[N(CH3)2]3, CH3B[N(CH3)2]2 und (CH3)2BN(CH3)2 in linearer Beziehung. Dies gilt auch für die Reihe der Guanidinium-, Amidinium- und Imonium-Ionen und die mit ihnen isoelektronischen aminoborane. Ein Vergleich der δ13C- und der δ11B-Daten für die erste Verbindungsreihe spiegelt zwar die zunehmende positive Ladung am betrachteten Zentrum  -  allerdings nur im Trend - wieder, da keine lineare Korrelation erkennbar ist. Diese 1st. Diese ist jedoch für die Reihe der Carbonium-Ionen und Borane gegeben. Es gilt δ11B = 0.393 δ 13C - 30.73. Für BH3 leitet sich δ 11B zu -70.0 ppm ab.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19741070930
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  • 8
    Electronic Resource
    Electronic Resource
    Beiträge zur Chemie des Bors, LXVIII. Cyclische Verbindungen mit Bor, Stickstoff und Phosphor als Ringgliedern („Phosphaborazine“) (1974)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 107 (1974), S. 3806-3817 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Boron, LXVIII. Cyclic Compounds with Boron, Nitrogen, and Phosphorus as Ring Members (‘Phosphaborazines’)N-Metalated ‘triazaboradecalin’ reacts with (CIRP)2 NR′ and [Cl2P(O)]2NCH3, respectively, with ring formation yielding ‘phosphaborazines’ of the type 14. Ring closure to a B2N3P-ring system 17, is also achieved by SiN-cleavage from the BNSi-chain compound 15 with CH3P(O)Cl2, but BN-cleavage dominates. Spectroscopic data indicate the ring system 17 not to be planar, furthermore, that with the exception of 14a all other derivatives of 14 are formed in one geometric form only.
    Notes: N-Metalliertes„Triazaboradecalin“ reagiert mit ( (CIRP)2 NR′ bzw. [Cl2P(O)]2NCH3 unter Ringschluß zu„Phosphaborazinen“ des Typs 14. Die Heterocyclensynthese zu einem B2N3P-Ringsystem 17 gelingt auch durch SiN-Spaltung der BNSi-Kettenverbindung 15 mit CH3 P(O)Cl2, wobei allerdings die BN-Spaltung dominiert. Die spektroskopischen Daten legen ein nicht planares Ringsystem 17 nahe. Mit Ausnahme von 14a werden alle Derivate von 14 in geometrisch einheitlicher Form erhalten.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19741071211
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  • 9
    Electronic Resource
    Electronic Resource
    Beiträge zur Chemie des Bors, L Dimethylamino-polyborane (1970)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 516-527 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Boron, L Dimethylamino-polyboranesDehalogenation of chloro(dimethylamino)boranes such as R2NBCI2, (R2N)2BCl or (R2N)3B2C1 (R = CH3) by liquid Na K-alloy yields dimethylaminopolyboranes of the type Bn(NR2)n + 2. The boron atoms form chains in these type of compounds and this chain is retained on partial substitution of their dimethylamino groups by chlorine. Tris(dimethyl-amino)borane and Tris(dimethylamino)boroxine are formed by the reaction of molecular oxygen with B3[N(CH3)2]5 or B4[N(CH3)2]6.
    Notes: Durch Enthalogenieren von Chlor-dimethylamino-boranen wie R2NBCl2, (R2N)2BC1 oder (R2N)3B2C1 (R = CH3) mit Na/K-Legierung erhält man Dimethylamino-polyborane Bn(NR2)n + 2 mit kettenförmiger Verknüpfung der Boratome. Partielle Substitution der R2N-Gruppen in den Polyboranderivaten durch Chlor ist unter Erhalt der Kettenstruktur möglich. Oxydation von B3[N(CH3)2]5 bzw. B4[N(CH3)2]6 mit Sauerstoff liefert B[N(CH3)2]3 und [(CH3)2NBO]3.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19701030221
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  • 10
    Electronic Resource
    Electronic Resource
    Beiträge zur Chemie des Bors, LVII. Monomere Phosphino-, Arsino- und Stibinoborane (1972)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 105 (1972), S. 1962-1971 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Boron, LVII. Monomeric Phosphino-, Arsino- and StibinoboranesThe reactions of (dialkylamino)haloboranes with LiP(CH3)2, LiAs(C2H5)2, or LiSb(C2H5)2 yield the following monomeric borane derivatives: [(CH3)2N]2B—P(CH3)2, [(CH3)2N]2- B—As(C2H5)2, [(CH3)2N]2B—Sb(C2H5)2, and (C2H5)2N—B[As(C2H5)2]2. Their n.m.r. spectra as well as those of [(CH3)2N]2B—P(C2H5)2 and (C2H5)2N—B[P(C2H5)2]2 are discussed.
    Notes: Die Umsetzung von Dialkylaminoborhalogeniden mit LiI(CH3)2, LiAs(C2H5)2 bzw. LiSb(C2H5)2 liefert die folgenden monomeren Boran-Derivate: [(CH3)2N]2B—P(CH3)2, [(CH3)2N]2B—As(C2H5)2, [(CH3)2N]2B—Sb(C2H5)2 sowie (C2H5)2N—B[As(C2H5)2]2. Ihre NMR-Spektren sowie jene von [(CH3)2N]2B—P(C2H5)2]2 und (C2H5)2N—B[P(C2H5)2]2 werden diskutiert.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19721050621
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