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  • Cell & Developmental Biology  (89)
  • Inorganic Chemistry  (12)
  • 1
    Electronic Resource
    Electronic Resource
    Notiz zur Veröffentlichung von W. Sucrow und B. Radüchel: „Die synthese von (24(28)Z)-Δ7.24(28)-5α-Stigmastadienol-(3β)“ (1970)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 655-655 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19701030240
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  • 2
    Electronic Resource
    Electronic Resource
    Neue Synthesen und Reaktionen von Phosphetaniumsalzen mit planarem Gerüst (1992)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 1987-1997 
    Details
    ISSN: 0009-2940
    Keywords: Phosphetanium salts ; Phosphoranes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Novel Syntheses and Reactions of Phosphetanium Salts with a Planar SkeletonCleavage of the P-Si bond of silylphosphanes R2P-SiMe3 (R = iPr, tBu, 2,4,6-Me3C6H2) with excess 1,3-dihalogenpropanes X-[CH2]3-X (X = Br, I) affords phosphetanium salts (3) in good yields. These strained four-membered ring systems are also obtained by alkylation of secondary phosphanes R2PH with X-[CH2]3-X followed by deprotonation of the intermediate phosphonium salts [R2P(H) - [CH2]3-X]+ X- (R e.g. tBu; X = Br, 7b). Silylphosphanes and secondary phosphanes with less bulky substituents preferably form open-chain phosphonium salts with [CH2]3-X or allyl substituents in these reactions. X-ray structural analysis of (3h) reveals planar geometries for the PC3 skeletons of the cations. The reactivity of 3b towards different types of nucleophiles [F-, NH2-, OH-, OR-, Fe(CO)2Cp-, NaN(SiMe3)2, RR′PLi] has been studied. Reaction with CsF or NaNH2, leads to a stable monofluoro or monoamino phosphorane, respectively, with cyclic four-membered PC3 skeletons. In all other cases opening of the phosphetanium ring system occurs leading to derivatives with R2P - [CH2]3 terminal groups. Bidentate and polydentate ligands, e.g. 19-25, with bulky substituents in terminal position have been synthesized in high yields by cleavage of 3b with mono- and bifunctional lithium phosphides. By deprotonation of 3b with MeLi the cyclic ylide 14 is formed. Treatment with acetone or benzaldehyde leads to the unsaturated open-chain phosphane oxides 15a or 15b in a Wittig-type reaction.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19921250904
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  • 3
    Electronic Resource
    Electronic Resource
    Reaktionen koordinierter Liganden, XIV. Synthese eines vierzähnigen Phosphor-Makrocyclus im Palladium(II)-Templat (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 349-365 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of Coordinated Ligands, XIV. Synthesis of a Tetradentate Phosphorus Macrocycle in a Palladium(II) TemplateCyclisation of the disecondary phosphane HMeP—CH2—CH2-PMeH (1) with o-xylylene dichloride within a PdII template affords tetradentate macrocyclic complexes (5a-c) as mixture of three diastereoisomers Recrystallisation from methanol yields the pure syn-(RSRS) isomer (5a · CH3OH). X-ray crystal structure determination (orthorhombic, space group P212121) reveals a 16-membered tetradentate ring system. The four phophorus atoms and one chlorine form a square pyramidal arrangement at palladium in the monocation [Pd(7)Cl]+ (Pd—P = 2.302(1), 2.304(1), 2.311(1), 2.306(1), Pd—Cl = 3.107(1)Å). Both seven-membered chelate ring systems adopt a chair configuration. If the palladium complexes 5a-c are treated with KCN, the macrocyclic ligand may be released from the template center and transferred to another transition metal (10, 11).
    Notes: Die Cyclisierung des disekundären Phosphans HMeP—CH2—CH2—PMeH (1) mit o-Xylylendichlorid im PdII-Templat liefert den Komplex des vierzähnigen makrocyclischen Liganden 7 in hoher Ausbeute als Gemisch dreier Stereoisomerer (5a-c). Umkristallisation aus Methanol liefert das syn-(RSRS)-Isomere in reiner Form (5a · CH3OH). Nach der Röntgenstrukturanalyse (orthorhombisch, Raumgruppe P212121) liegt im ionogen aufgebauten Komplex [Pd(7)Cl]+Cl-. CH3OH ein 16-gliedriges Ringsystem vor, das mit seinen vier P-Atomen die Basis der quadratisch pyramidalen Ligandenanordnung im Monokation bildet (Pd—P = 2.302(1), 2.304(1), 2.311(1), 2.306(1), Pd—Cl = 3.107(1)Å). Die beiden siebengliedrigen Chelatringe besitzen Sesselkonformation. Durch Behandeln der Palladiumkomplexe 5a-c mit KCN läßt sich der makrocyclische Ligand vom Templatzentrum ablösen und auf andere Übergangsmetalle übertragen (10, 11).
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190130
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  • 4
    Electronic Resource
    Electronic Resource
    Lineare Oligophosphaalkane, XVI Achtgliedrige Ringverbindungen von Kupfer(I) und Silber(I) mit PH-funktionellen P - C - P-Brücken (1987)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 120 (1987), S. 81-87 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: With CuCl the secondary-tertiary methylenebisphosphane (iPr)2P - CH2 - P(iPr)H (1) forms a metal complex Cu2Cl2(1)2. The X-ray structural analysis of 2 (space group P21/a) shows a puckered eight-membered ring system formed by two ligands 1 and two trigonal planar Cu1 ions [Cu - P(1) 2.227(1), Cu - P(2′) 2.247(1), Cu - Cl 2.248(1) Å]. Reaction of 1 with AgBF4 or [Cu(CH3CN)4]PF6 leads to the formation of ionic complexes[Ag2(1)2[BF4]2 (4) or [Cu2(1)2(CH3CN)2][PF6]2 (3), repectively. The 1:2 complexes of 1 formed with CuCl or AgCl (5, 6) are assigned a dimeric structure M4Cl4(1)2 on the basis of mass spectroscopic and cryoscopic studies. Metal-ligand exchange observed in the temperature dependent 31P{1H}-NMR spectra of 6 is faster for the (iPr) HP-donor sit compared to the exchange reaction at the tertiary group (iPr)2P.
    Notes: Das Methylenbisphosphan (iPr)2P - CH2 - P(iPr)H (1) bildet mit CuCl einen neutralen Komplex (2) der Zusammensetzung Cu2Cl2(1)2. Nach den Ergebnissen der Röntgenstrukturanalyse (Raumgruppe P21/a) liegt in 2 ein gewelltes achtgliedriges Ringsystem vor, das aus zwei Liganden 1 und zwei CuI-Ionen mit trigonal planarer Koordination aufgebaut ist [Cu-P(1) 2.227(1), Cu - P(2′) 2.247(1), Cu - Cl 2.248(1) Å]. Die Umsetzung von 1 mit AgBF4 bzw. [Cu(CH3CN)4]PF6 führt zu ionogenen Komplexen [Ag2(1)2[BF4]2 (4) bzw. [Cu2(1)2(CH3CN)2][PF6]2 (3). Den 1:2-Komplexen von 1 mit CuCl und AgCl (5, 6) kommt nach massenspektroskopischen Untersuchungen und der kryoskopischen Bestimmung der Molmassen die Zusammensetzung M4Cl4(1)2 zu. Metall-Ligand-Austauschprozesse verlaufen an den (iPr)2P- und (iPr)HP-Gruppierungen in Ag4Cl4(1)2 (6) mit unterschiedlicher Geschwindigkeit ab, wie die Temperaturabhängigkeit der 31P{1H}-NMR-Spektren zeigt.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19871200115
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  • 5
    Electronic Resource
    Electronic Resource
    Reaktionen koordinierter Liganden, XVIII. Templatsynthesen und Peripheriereaktionen makrocyclischer Multiphosphanliganden mit funktionellen Gruppen (1992)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 1785-1794 
    Details
    ISSN: 0009-2940
    Keywords: Template synthesis ; Phosphane complexes, macrocyclic, tetradentate ; Periphery reactions ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactions of Coordinated Ligands, XVIII. - Template Syntheses and Periphery Reactions of Macrocyclic Multiphosphane Ligands with Functional GroupsCyclisation of the tridentate phosphanes PhP([CH2]3PRH)2 (R = H, Me) with the divinyl components R′P(CH=CH2)2 [R′ = Ph, NEt2, O(iPr)] within Ni(II) templates affords complexes NiBr2L (3a-f) of functionalised macrocyclic tetraphosphanes (L) in almost quantitative yields. An X-ray structural analysis of the cyano complex [Ni(CN)L]PF6 (5a), obtained by metathetical reactions, reveals a folded 14-membered macrocyclic ligand L. The P atoms occupy axial and equatorial positions within the trigonal-bipyramidal ligand arrangement with an equatorial CN group. By periphery reactions at the P-NEt2 function of the 14-membered ring system P—OH, P—O-, P—Cl, P—OR″ derivatives (R″ = Me, iPr, CH2CH=CH2) are formed. Addition of methyl acrylate to the P—H functions in 3d and 3f leads to macrocyclic diesters 12a, 12b. By cleavage of the P—N bond in 3a with concentrated aqueous HBr a complex of composition 7a · HBr · 3 H2O is obtained. An X-ray structural analysis of the latter shows a P—OH functionalised macrocyclic tetraphosphane occupying the four basal positions within a square pyramidal coordination geometry at Ni(II).
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19921250802
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  • 6
    Electronic Resource
    Electronic Resource
    Neue Reaktionen von Schwefeldiimiden mit elektronenreichen und elektronenarmen Alkinen (1987)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 120 (1987), S. 751-760 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Depending on the reaction conditions, the sulfur diimides 1a, b react with the ynamines 2a-c to produce 3a, 4a-d or 6a-d and 8, whereas the reactions of 1a, c, d with 2a, c give the amidines 6e-h. Furthermore, the reactions of 4a with 2c or of 1a with 2b, c lead to products of type 12. On the other hand, dimethyl acetylenedicarboxylate (2d) reacts with 1e to form 17 and 18, whereas the reaction of 1f with 2d leads to the 2(1H)-pyridinone derivative 21. Spectroscopic data as well as the results of an X-ray analysis of 6e are consistent with the structures.
    Notes: In Abhängigkeit von den Reaktionsbedingungen reagieren die Schwefeldiimide 1a, b mit den Inaminen 2a-c zu 3a, 4a-d oder 6a-d und 8, während die Reaktionen von 1a, c, d mit 2a, c die Amidine 6e-h ergeben. Weiterhin führen die Reaktionen von 4a mit 2c oder von 1a mit 2b, c zu Produkten vom Typ 12. Andererseits reagiert Acetylendicarbonsäure-dimethylester (2b) mit 1e zu 17 und 18, während die Umsetzung von 1f mit 2d das 2(1H)-Pyridinon-Derivat 21 liefert. Spektroskopische Daten sowie die Ergebnisse der an 6e durchgeführten Röntgenstrukturanalyse belegen die Konstitutionen.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19871200512
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  • 7
    Electronic Resource
    Electronic Resource
    Pyrrolo[1,2-b]-1,3,4-thiadiazol-Derivate aus mesomeren Heteropentalenen und Azodicarbonestern (1988)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 121 (1988), S. 95-104 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Pyrrolo[1,2-b]-1,3,4-thiadiazole Derivatives from Mesomeric Heteropentalenes and Azodicarboxylic EstersThe mesomeric heteropentalene betaines of type 4, 7, and 18 display an unusual reaction behavior against the azodicarboxylic esters 8a-c. Surprisingly, 4 reacts with 8a, b to produce 17a, b, whereas the reaction of 4 with 8c leads to 11 and the novel azomethine imine 15. Also the reaction of 18 with 8a-c gives in two cases 20 or 25 beside the azomethine imine 19. Furthermore, 7 reacts with 8a to form 26, whereas the reaction of 7 with 8c surprisingly yields 29. Spectroscopic data as well as the results of the X-ray analyses of 17a and 19 are consistent with the structures.
    Notes: Die mesomeren Heteropentalen-Betaine vom Typ 4, 7 und 18 reagieren mit den Azodicarbonestern 8a-c ungewöhnlich. So liefert 4 mit 8a, b überraschend 17a, b, während die Umsetzung von 4 mit 8c zu 11 und dem neuen Azomethin-imin 15 führt. Auch die Reaktionen von 18 mit 8a-c ergeben neben dem Azomethinimin 19 noch in zwei Fällen 20 oder 25. Weiterhin reagiert 7 mit 8a zu 26, wogegen die Umsetzung von 7 mit 8c überraschend zu 29 führt. Spektroskopische Daten sowie die Ergebnisse der an 17a und 19 durchgeführten Röntgenstrukturanalyse belegen die Konstitutionen.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19881210115
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  • 8
    Electronic Resource
    Electronic Resource
    Lineare Oligophosphaalkane, XIV. Synthese und Struktur funktionalisierter 1,2,3,5-Diazadiphospholane (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2767-2776 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Linear Oligophosphaalkanes, XIV. Synthesis and Structure of Functionalized 1,2,3,5-DiazadiphospholanesThe methylenebisphosphanes RC1P—CH2—PC1R (1, 6a, b) (R = Cl, iPr, tBu) react with hydrazine, N,N′-dimethylhydrazine, or phthalohydrazide to give five-membered mono- or bicyclic hydrazinophosphanes 2-4, 7a, b, and 8. The unsymmetrically substituted bicyclic hydrazinophosphane 5 is accessible by a two-stage synthesis. On reaction of 6b with hydrazine the trans-isomer (racemic form) of 7b is formed significantly faster than the cis-isomer. At 60°C it rearranges within several hours to yield the thermodynamically stable trans-form. The X-ray structural analysis of 7b (monoclinic, space group P21/n; a = 1226.1(2), b = 593.32(7), c = 1745.2(2) pm,β = 90.46(1)°) shows a folded five-membered ring with the substituents in all-trans position on P and N (P1-C1 185.0(2), P2-C1 184.6(2), P1-N1 172.9(2), P2-N2 170.9(2), N1-N2 145.4(3) pm).
    Notes: Durch Umsetzung der Methylenbisphosphane RC1P—CH2—PC1R (1, 6a, b) (R = Cl, iPr, tBu) mit Hydrazin, N,N′-Dimethylhydrazin bzw. Phthalsäurehydrazid lassen sich fünfgliedrige mono- und bicyclische Hydrazinophosphane 2-4, 7a, b und 8 darstellen. Das unsymmetrisch substituierte bicyclische Hydrazinophosphan 5 ist in einer Zweistufenreaktion zugänglich. Das trans-Isomere (Racemat) von 7b bildet sich bei der Umsetzung von 6b mit Hydrazin wesentlich rascher als die cis-Verbindung (Mesoform). Sie lagert sich bei 60°C innerhalb weniger Stunden in das thermodynamisch stabilere trans-Isomere um. Die Röntgenstrukturanalyse von 7b (monoklin, Raumgruppe P21/n; a = 1226.1(2), b = 593.32(7), c = 1745.2(2) pm, β = 90.46(1)°) zeigt das Vorliegen eines gewellten Fünfrings mit all-trans- Position der Substituenten an P und N (P1 -C1 185.0(2), P2-C1 184.6(2), P1 - N1 172.9(2), P2-N2 170.9(2), N1 -N2 145.4(3) pm).
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190909
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  • 9
    Electronic Resource
    Electronic Resource
    Reactions of (CF3)2BNMe2 with ω-Halonitriles  -  Crystal and Molecular Structure of [cyclo-C3H4(CN)](CF3)2B·NHMe2Dedicated to Professor Peter Sartori on the occasion of his 65th birthday. (1996)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 129 (1996), S. 1541-1545 
    Details
    ISSN: 0009-2940
    Keywords: Dimethylaminobis(trifluoromethyl)borane ; Nitriles ; Cyclopropanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Dimethylaminobis(trifluoromethyl)borane, (CF3)2BNMe2 (A), reacts with Cl(CH2)3CN to yield [Cl(CH2)2CH(CN)](CF3)2B·NHMe2 (1) whereas Br(CH2)3CN and A combine in a 1:2 ratio to form [cyclo-C3H4(CN)](CF3)2B·NHMe2 (2) and Br(CF3)2B·NHMe2. Br(CH2)nCN and A yield [Br(CH2)n-1 CH-(CN)](CF3)2B·NHMe2, n=4 (3), n=5 (4) and n=6 (5). Compound 2 and (NCCH2)CF3)2B·NHMe2 can be alkylated at nitrogen with CH3I/KOH in ether to yield [cyclo-C3H4(CN)]-(CF3)2B·NMe3 (6) and (NCCH2)(CF3)2B·NMe3 (7), respectively. treatment of 1 and 3 with hydroxide in ether gives the respective five- and six-membered heterocycles (CF3)2 (8) and (9). Reduction of the nitrile group with (iBu)2Alh in CH2Cl2 at -50°C followed by hydrolysis furnishes the corresponding aldehydes (OCHCH2) (CF3)2B·NMe3 (10), [cyclo-C3H4(CHO)](CF3)2B·NMe3 (11) and (12). The structure of 2 was determined by an X-ray investigation.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19961291222
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  • 10
    Electronic Resource
    Electronic Resource
    Die Molekülstrukturen zweier Komplexe mit Dimethylphosphonium-bis(methylid) als Liganden (1974)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 107 (1974), S. 3706-3715 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Molecular Structure of two Complexes with Dimethylphosphonium-bis(methylide) as LigandsThe X-ray analyses of one isomeric form (1) of the compound dinickel-tetrakis[dimethylphosphonium-bis(methylide)] and of dimethylbis(trimethylphosphine)cobalt(III)-[dimethylphosphonium-bis(methylide)] (2) were carried out and the results are discussed. Both compounds contain the new ligand dimethylphosphonium-bis(methylide). In the nickel compound the ligand bridges two nickel atoms and also acts as a chelating ligand.
    Notes: Es werden die Röntgenstrukturanalysen einer isomeren Form (1) des Dinickel-tetrakis[dimethylphosphonium-bis(methylids)] (a = 11.8445(6), b = 10.7782(8), c = 9.3078(6) Å, β = 99.672(6)°, R = 0.037) sowie des Dimethylbis(trimethylphosphin)kobalt(III)-[dimethyl-phosphonium-bis(methylids)] (2) (a = 9.0217(11), b = 11.767(2), c = 9.0769(9) Å, β = 109.12(1)°, R = 0.062) vorgestellt und die gefundenen Bindungsverhältnisse diskutiert. In beiden Verbindungen tritt der neuartige Ligand Dimethylphosphonium-bis(methylid) auf, wobei er in der Nickelverbindung sowohl als Chelat-Ligand wie auch als verbrückender Ligand beobachtet wird.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19741071124
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