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  • 1
    Electronic Resource
    Electronic Resource
    Strukturchemische Untersuchungen an Verbindungen mit formalen , und -Heteroalleneinheiten (1982)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 115 (1982), S. 2981-2996 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Structural Chemical Investigations on Compounds with Formal , and Heteroallene UnitsX-ray structures and syntheses of an (alkylidenamino)sulfonium salt (8), of an (alkylidenamino)-phosphonium salt (9c), and of a sulfimidophosphonium salt (10) are reported. These compounds which can formally be regarded as heteroallenes , , and , resp., are bent pseudoallenes in the crystal. The C—N—S bond angle of 8 is 118°. The positive charge is located on sulfur. According to 13C DNMR measurements 8 is bent also in solution. The bond angle of the C—N—P unit in solid 9c is 128°. The positive charge is delocalized between P and N. The activation energy of the geometrical isomerization around the C=N double bond in 9a, e in solution has been measured by dynamic 13C NMR spectroscopy to be ΔGTc≠ = 32.5 and 30.6 ± 1 kJmol-1, respectively. The S—N—P bond angle in 10 is 124°. The positive charge is delocalized between S and P.
    Notes: Es werden Synthesen und Röntgenstrukturanalysen eines (Alkylidenamino)sulfoniumsalzes (8), eines (Alkylidenamino)phosphoniumsalzes (9c) und eines Sulfimidophosphoniumsalzes (10) beschrieben. Diese als Heteroallene , bzw. formulierbaren Verbindungen sind im Kristall alle gewinkelte Pseudoallene. Verbindung 8 zeigt einen C-N-S-Bindungswinkel von 118°. Die positive Ladung ist am Schwefel lokalisiert. Nach 13C-DNMR-Messungen liegt 8 auch in Lösung gewinkelt vor. Der Bindungswinkel der C—N—P-Einheit in 9c beträgt im Kristall 128°. Die positive Ladung ist zwischen P und N delokalisiert. Für die Aktivierungsenergie der geometrischen Isomerisierung um die C=N-Doppelbindung in 9a, e werden in Lösung aus temperaturabhängigen 13C-NMR-Spektren δGTc≠ = 32.5 bzw. 30.6 ± 1 kJmol-1 gemessen. Der S—N—P-Bindungswinkel in 10 beträgt 124°. Die positive Ladung ist zwischen S und P delokalisiert.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19821150905
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  • 2
    Electronic Resource
    Electronic Resource
    2-Azaallenium salts from the reaction of 1-oxa-3-azabutatrienium salts with cyanamides and carbodiimides (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1887-1902 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Darstellung von 2-Azaallenium-Salzen durch Reaktionen von 1-Oxa-3-azabutatrienium-Salzen mit Cyanamiden und CarbodiimidenDie 1-Oxa-3-azabutatrienium-Salze 2 reagieren mit disubstituierten Cyanamiden unter [2 + 2 + 2]-Cycloaddition zu den 2-(Alkylidenamino)-4,6-diamino-1,3,5-oxadiazinium-Salzen 7a - o, die man als oxysubstituierte 2-Azaallenium-Salze betrachten kann. Durch Anlagerung von Methanol entstehen die Oxadiazinium-Salze 8a, d, p. Aus 2n und Dimethylcyanamid erhält man das 2-Azaallenium-Salze 11, dessen Bildung eine [1,5]-isocyanatotrope Umlagerung einschließt. Die Butatrienium-Salze 2 reagieren meist mit zwei Äquivalenten Carbodiimid vom Typ R1 — N = C = N — CHR22 zu den 2-Azaallenium-Salzen 17a - k, die durch eine [1,5]-Hydridverschiebung entstehen. Sterisch anspruchsvoll substituierte Butatrienium-Salze 2 lagern drei Moleküle Diisopropylcarbodiimid and und ergeben die 1,3,5-Triazinium-Salze 20n, o. Es werden Röntgenstruktur-analysen der Verbindungen 7a und 17a angegeben.
    Notes: 1-Oxa-3-azabutatrienium salts 2 react with disubstituted cyanamides under [2 + 2 + 2] cycloaddition affording the 2-(alkylideneamino)-4,6-diamino-1,3,5-oxadiazinium salts 7a - o, which can be regarded as oxy-substituted 2-azaallenium salts. Addition of methanol leads to the oxadiazinium salts 8a, d, p. From 2n and dimethylcyanamide the 2-azaallenium salt 11 was obtained, which must be formed by an [1,5] isocyanatotropic rearrangement. Most butatrienium salts 2 react with two equivalents of carbodiimides R1 — N = C = N — CHR22 to form the 2-azaallenium salts 17a - k. The reaction mechanism includes an [1,5] hydride shift. Bulky substituted butatrienium salts 2 add three molecules of diisopropylcarbodiimide to give the 1,3,5-triazinium salts 20n, o. X-Ray structural analyses for 7a and 17a are reported.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19851180514
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  • 3
    Electronic Resource
    Electronic Resource
    Metal Complexes of Cyanamides and their Alkylation to Cyanamidium Salts. A General Synthesis of Highly Substituted Ureas, Isoureas, and Guanidines (1984)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 117 (1984), S. 1161-1177 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Metallkomplexe von Cyanamiden und ihre Alkylierung zu Cyanamidiumsalzen. Eine allgemeine Synthese hochsubstituierter Harnstoffe, Isoharnstoffe und GuanidineAus disubstituierten Cyanamiden und Lewis-Säuren werden die Komplexe 3a - p erhalten. Nach einer Röntgenstrukturanalyse hat der Antimonpentachlorid-Komplex 3a weder s̰- noch π-Symmetrie ( ∡ C≡N - Sb 133°). Die Komplexe 3 mit SbCl5 oder FeCl3 können mit tertiären Alkylchloriden zu den kristallinen Cyanamidiumsalzen 5a - m alkyliert werden. Mit Wasser, primären oder sekundären Alkoholen reagieren die Verbindungen 5 zu Harnstoffen (11) bzw. Uroniumsalzen (8a - z), mit Ammoniak, primären oder sekundären Aminen zu Guanidiniumsalzen (9a - s).
    Notes: The complexes 3a - p were prepared from disubstituted cyanamides and Lewis acids. According to a X-ray structural analysis, the antimony pentachloride complex 3a is neither a s̰ nor a π complex (∡ C≡N - Sb 133°). The complexes 3 with SbCl5 and FeCl3 can be alkylated with tertiary alkyl chlorides, affording crystalline cyanamidium salts (5a - m) which were characterized by reactions with water, primary or secondary alcohols to give ureas (11) and uronium salts (8a - z), respectively. The guanidinium salts 9a - s were obtained with ammonia, primary and secondary amines.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19841170330
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  • 4
    Electronic Resource
    Electronic Resource
    Zum Koordinationsverhalten von Alkinylphosphanen RnP(C≡C-R')3-n (1991)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 259-264 
    Details
    ISSN: 0009-2940
    Keywords: Alkynylphosphines ; Cobalt complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Coordination Ability of Alkynylphosphines RnP(C≡C - R')3 - nAlkynylphosphines RP(C≡C-R')2 (2) react with one equivalent of octacarbonyldicobalt to yield selectively the η2-μ side-on-coordinated alkyne complexes (R)(R' - C≡C)P[(η2-C≡C-R')Co2(CO)6] (6); with another equivalent of Co2(CO)8 the dicoordinated compounds (R)P[(η2-C≡C-R')Co2(CO)6]2 (7) are obtained. 7 may also be synthesized directly by the reaction of 2 with two equivalents of Co2(CO)8. However, P(C≡C-Ph)3 yields with two equivalents of Co2(CO)8 the cyclic Co2P2C2 system {(Ph-C≡C)(R')P[(η2-C≡C-Ph)Co2(CO)5]} 2 (4) [R' = (η2-C≡C-Ph)Co2(CO)6]. Decarbonylation of 6a gives the six-membered cyclic compound {(Ph)(Ph - C ≡ C)P[(η2-C ≡ C - Ph)Co2(CO)5]}2 (8), while 6b yields the cluster Co3(CO)9(μ3-PtBu) (9). The structure of (tBu)P[(η2-C ≡ C - H)Co2)CO)6]2 (7b) is elucidated by an X-ray analysis.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19911240203
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  • 5
    Electronic Resource
    Electronic Resource
    Mixed amide thiolate complexes of zinc with low coordination number at the metal atom (1992)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 2199-2207 
    Details
    ISSN: 0009-2940
    Keywords: Zinc complexes ; Low coordination ; Amide complexes ; Thiolate complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Three 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.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19921251006
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  • 6
    Electronic Resource
    Electronic Resource
    Dimeric Silver(I) Complexes of Some Isothiazole-Based LigandsDedicated to Prof. Dr. Rolf Gleiter on the occasion of this 60th birthday. (1997)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 95-100 
    Details
    ISSN: 0009-2940
    Keywords: Isothiazole complexes ; Dinuclear silver(I) complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of isothiazole-based potential ligands bearing substituents with additional donor sites in the 5-position of the heterocycle was synthesized [3-Me-5-R-C3HNS; R = CH=N(CH2)2py (1), CH=NCH2py (2), CH2N(CH2CH2NEt2)2 (4), (CH2)2SMe (5)]. Upon reaction with AgO3SCF3 they formed complexes [(1)AgOSO2CF3]2 (6), [(2)AgOSO2CF3]2 (7), [(4)Ag]2+2(O3SCF-3)2 (8) and [(5)AgOSO2CF3]2 (9), respectively. 6, 8 and 9 were shown by X-ray structural analyses to consist of dimeric units L2Ag2+2, either discrete (8), coordinated by terminal CF3SO-3 units (6). In 8 and 9 the isothiazole moiety is bonded to the metal center via the ring-N. The coordination potential of the isothiazole heterocycle is discussed.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19971300115
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  • 7
    Electronic Resource
    Electronic Resource
    Reaktionen des Tripod-Co-Templats CH3C(CH2PPh2)3Co(II) mit funktionalisierten HydrazinenMax Herberhold zum 60. Geburtstag gewidmet. (1996)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 129 (1996), S. 1107-1113 
    Details
    ISSN: 0009-2940
    Keywords: Tripod ligands ; Hydrazines, substituted ; Diazenes ; Cobalt(III), fivefold coordination of ; Cobalt(II), fivefold coordination of ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The coordination behaviour of ligands having the same basic constitution RN=NC(=X)R′ (X = O, NR″, S) in their tripod cobalt derivatives has been analyzed. The ligands themselves may be considered as neutral heterodiene compounds and are in this respect vinylogues to diazenes RN=NRy′. Two- electron reduction of these neutral species results in dianionic heterosubstituted heteroolefins RN- -N=C(X-)R′. Due to their redox ambiguity the oxidation state of the metal M in chelate complexes is not a priori evident. Compounds tripod [5: X, R′ = O, Ph; 6; (X, R′) = (py); 7: X, R′ = S, NH2] are best described as containing low-spin Co(III) and dianionic ligands. Co(II) species are obtained with diethyl azodicarboxylate EtOOCN=NCOOEt as the ligand. In the mononuclear compound, with only one nitrogen and one carbonyl oxygen of the ligand acting as donor groups, the neutral ligand is coordinated to give the high-spin cobalt(II) species tripod (8). In the dinuclear compound 9 with both of the nitrogen atoms and carbonyl groups involved in coordination the dianionic ligand bridges two high-spin cobalt(II) centers to give tripod (9) as a derivative with two fused five-membered chelate rings. In addition to the conventional analytical techniques X-ray structure analyses, cyclovoltametric measurements, magnetic susceptibility and ESR data are used to characterize the compounds.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19961290921
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  • 8
    Electronic Resource
    Electronic Resource
    Substituierte einkernige Carbonyleisendihydride (1981)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 114 (1981), S. 3549-3557 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Substituted Mononucleus Carbonyliron HydridesSubstitution of H2Fe(CO)4 by ligands like L = As(C6H5)3, Sb(C6H5)3 and P(OC6H5)3 in 1:1 ratio leads to fac monosubstituted compounds H2Fe(CO)3L. A 1:2 ratio results in the isolation of disubstituted complexes H2Fe(CO)2L2, L = P(OCH2)3CC2H5, P(OC6H5)3. The structure of H2Fe(CO)3As(C6H5)3 Was elucidated by X-ray analysis.
    Notes: Substitution von H2Fe(CO)4 mit Liganden L = As(C6H5)3, Sb(C6H5)3 und P(OC6H5)3 im Molverhältnis 1:1 Führt zu fac-Monosubstitutionsverbindungen H2Fe(CO)3L. Im Verhältnis 1:2 können trans-Disubstitutionskomplexe H2Fe(CO)2L2, L = P(OCH2)3CC2H5, P(OC6H5)3, erhalten werden. Von H2Fe(CO)3As(C6H5)3 wurde eine Röntgenstrukturanalyse ausgeführt.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19811141108
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  • 9
    Electronic Resource
    Electronic Resource
    Cyanamidiumsalze: Bildung und Bau (1981)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 114 (1981), S. 3655-3666 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cyanamidium Salts: Their Formation and Molecular StructureThe hexachloroantimonate 6a, is prepared by methylation of di-tert-butylcarbodiimide. According to an X-ray analysis, 6a is not a carbodiimidium salt 1) but a cyanamidium salt with C2ν symmetry of the molecular frame. the cyanamidium salts 6a - j, are prepared either by alkylation of carbodiimides1) or by alkylation of disubstituted cyanamides. Trisubstituted ureas or their thio analogues are not suitable starting materials for the preparation of compounds 6. Reactions of the cyanamidium salts 6 with HCl, water, and diethylamine are described.
    Notes: Das durch Methylierung von Di-tert-butylcarbodiimid erhältliche Hexachloroantimonate 6a liegt nach einer Röntgenstrukturanalyse nicht als Carbodiimidium-1), sondern als Cyanamidiumsalz mit C2ν-Symmetrie des Molekülgerüstes vor. Die Cyanamidiumsalze 6a - j werden außer durch Alkylierung von Carbodiimiden 1) auch durch Alkylierung von disubstituierten Cyanamiden erhalten. Trisubstituierte Harnstoffe oder Thioharnstoffe sind keine geeigneten Ausgangsverbindungen zur Darstellung der salze 6. Es werden Umsetzungen der cyanamidiumsalze 6 mit HCl, Wasser und Diethylamin beschrieben.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19811141118
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  • 10
    Electronic Resource
    Electronic Resource
    Reaktionen von Arsiniden-Komplexen: Arsen als trigonal planar koordiniertes Brückenelement in dreikernigen Metallkomplexen (1982)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 115 (1982), S. 2035-2043 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reaction of Arsinidene Complexes: Arsenic Atoms as Trigonally Planar Coordinated Bridging Elements within Trinuclear Metal ComplexesThe synthesis of compounds in which all five valence electrons of a μ3-bridging arsenic atom are involved in bonding to three metal ligand fragments is achieved for the first time by the reaction of arsinidene complexes ClAs[MLn]2 (MLn = Cr(CO)5, Mn(CO)2(η5-CH3C5H4)) with η5-C5H5(CO)3Ml′- (M′ = Mo, W); chlorine substitution and MM′ bond formation with accompanying loss of one carbonyl group leads to the complexes 3, (3a, M′ = Mo, MLn = Mn(CO)2(η5-CH3C5H4); 3b, M′ = Mo, MLn = Cr(CO)5; 3c, M′ = W, MLn = Cr(CO)5). In compounds 3 there is no lone pair left at the μ3-arsenic atom which therefore shows trigonal planar coordination. The electron deficiency at the arsenic atom is compensated for by metal-arsenic η-bonding in a manner similar to the bonding situation in arsinidene complexes. X-ray analyses for 3a-c confirm this statement.
    Notes: Die erstmalige Synthese von Verbindungen, in denen alle fünf Valenzelektronen eines μ3-verbrückenden Arsenatoms in die Bindung zu drei Metall-Ligand-Fragmenten einbezogen sind, gelingt durch Umsetzung von Arsiniden-Komplexen ClAs[MLn]2 (MLn = Cr(CO)5, Mn(CO)2(η5-CH3C5H4)) mit η5-C5H5(CO)3M′- (M′ = Mo, W). In den unter Substitution der Chlorfunktion und Ausbildung einer M′M-Bindung unter CO-Abspaltung entstandenen Komplexen 3, (3a, M′ = Mo, MLn = Mn(CO)2(η5-CH3C5H4); 3b, M′ = Mo, MLn = Cr(CO)5; 3c, M′ = W, MLn = Cr(CO)5) besitzt das Arsen kein freies Elektronenpaar mehr. Es ist daher trigonal planar koordiniert; sein Elektronendefizit wird, wie in Arsiniden-Komplexen, durch π-Bindungsanteile in den Metall-Arsen-Bindungen ausgeglichen. Röntgenstrukturanalysen für 3a-c belegen dies.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19821150604
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