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  • 1
    ISSN: 0044-2313
    Keywords: P—Donor/Sn—Acceptor Ligands ; Pentacarbonyl Chromium Complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Alternative Ligands. XXXIV. Synthesis and Ligating Properties of P-Donor/Sn-Acceptor LigandsDonor/acceptor ligands of the type Me2PCH(R)OSnMe3 [R = H(5), Me (6), Ph (7)] have been prepared by reaction of Me3SnCl with HOCH(R)PMe2 and insertion of RCHO into the SnP bond of the stannylphosphane Me3SnPMe2, respectively. The new ligands, including the ethylen-bridged analogue Me2PCH2CH2SnMe3 (1), were used for the synthesis of the pentacarbonyl chromium complexes Cr(CO)5Me2PCH2CH2SnMe3 (11) and Cr(CO)5Me2PCH(R)OSnMe3 [R = H (12), Me (13), Ph (14)]. In addition, different routes were investigated to prepare the ligand 5-7 in the coordination sphere of the Cr(CO)5-fragment. For this purpose the ligands Me2PCH(R)OH [R = H (5′), Me (6′), Ph (7′)] and the complexes Cr(CO)5Me2PCH(R)OH [R = H (15), Me (16), Ph (17)], Cr(CO)5Me2PSnMe3 (18) and Cr(CO)5PMe2H (19) were prepared. Suitable pathways were found in the two-step process of 15-17 with nBuLi to give Cr(CO)5Me2PCH(R)OLi, followed by reaction with Me3SnCl, and the condensation of 15-17 with Me3SnCl using NEt3 as base. Besides ligands 5-7 were transformed to the corresponding phosphane sulfides Me2P(S)CH(R)OSnMe3 [R = H (8), Me (9), Ph (10)] by reaction with sulfur. Analytical (C, H) and spectroscopic investigations (NMR, IR, MS,Mößbauer), in addition to an X—ray diffraction study of 7, were performed to characterize the new compounds and to deduce information on structure and bonding.
    Notes: Donor/Akzeptor-Liganden des Typs Me2PCH(R)OSnMe3 [R = H (5), Me (6), Ph (7)] wurden durch Umsetzung von Me3SnCl mit HOCH2PMe2 bzw. durch Insertion von RCHO in die SnP-Bindung des Stannylphosphans Me3SnPMe2 dargestellt. Die neuen Liganden wurden unter Einbeziehung des ethylenverbrückten Vertreters Me3SnCH2CH2PMe2 (1) zur Synthese der Chrompentacarbonylkomplexe Cr(CO)5Me2PCH2CH2SnMe3 (11) und Cr(CO)5Me2PCH(R)OSnMe3 [R = H (12), Me (13), Ph (14)] genutzt. Zusätzlich wurden unterschiedliche Wege zur Darstellung der Liganden 5-7 in der Koordinationssphäre des Cr(CO)5-Fragments untersucht und dafür die Liganden Me2PCH(R)OH [R = H (5′), Me (6′), Ph (7′)] und die Komplexe Cr(CO)5Me2PCH(R)OH [R = H (15), Me (16), Ph (17)], Cr(CO)5Me2PSnMe3 (18) und Cr(CO)5PMe2H (19) dargestellt. Als geeignet erwiesen sich die zweistufige Umsetzung von 15-17 mit nBuLi zu Cr(CO)5Me2PCH(R)OLi, gefolgt von der Reaktion mit Me3SnCl, und die Kondensation von 15-17 mit Me3SnCl unter Verwendung von NEt3 als Hilfsbase. Die Liganden 5-7 werden schließlich noch mit Schwefel zu den Phosphansulfiden Me2P(S)CH(R)OSnMe3 [R = H (8), Me (9), Ph (10)] umgesetzt. Zur Charakterisierung und zur Absicherung der Bindungsbeschreibung dienen analytische (C, H) und spektroskopische Untersuchungen (NMR, IR, MS, Mößbauer) sowie für 7 eine Röntgenbeugungsanalyse an Einkristallen.
    Additional Material: 3 Ill.
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 411-414 
    ISSN: 0009-2940
    Keywords: Phosphaalkyne, amino- ; [3 + 2] Cycloaddition ; 1,2,4-Diazaphospholes ; 1,2,3-Diazaphospholes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactive E = C(p - p)π Systems, XXXII[1].  -  First Representatives of Amino-Substituted 1,2,4-Diazaphospholes(Diisopropylamino)phosphaethyne iPr2N - C≡P reacts at 20° C in a [3 + 2] cycloaddition with (trifluoromethyl)diazomethane (2a) or methyl diazoacetate (2b) to yield a mixture of the corresponding regioisomers 1H-1,2,4-diazaphospholes (5a or 5b) and 1H-1,2,3-diazaphospholes (6a or 6b) in quantitative yields (isomer ratio: 5a/6a = 2:1; 5b/6b = 4:1). X-ray diffraction studies on 5a and 5b indicate a delicate charge balance in the bonding system of 1H-1,2,4,σ2-diazaphospholes under the influence of the exocyclic push/pull substituents iPr2N and CF3 or CO2Me, respectively.
    Additional Material: 2 Ill.
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  • 3
    ISSN: 0009-2940
    Keywords: Phosphaalkyne, amino- ; Nickel carbonyl phosphane complex ; π Coordination ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactive E = C(p-p)π Systems, XXXIII.  -  Side-on Coordination of the Phosphaalkyne P ≡ C  -  N(iPr)2 in the 16e Nickel(0) Complex Ni(CO)PCy3[PCN(iPr)2]The reaction of (diisopropylamino)phosphaethyne P ≡ C  -  N(iPr)2 with the nickel complex [Ni(CO)3PCy3] - in contrast to the analogous reactions with Ni(CO)4 or Ni(CO)3PR3 (R = Me, Ph) - leads to the novel 16e nickel(0) system [Ni{η2-P ≡ C  -  N(iPr2)}(CO)PCy3] with a planar geometry of all skeleton atoms besides the methyl and cyclohexyl groups. Side-on coordination of the P ≡ C triple bond results in an increase of the PC distance to 1.665 Ȧ typical for phosphaalkenes.
    Additional Material: 1 Ill.
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  • 4
    ISSN: 0009-2940
    Keywords: Methylcarbene complexes of chromium and tungsten ; Cyclohexadienyl tricarbonyliron, carbene derivatives of ; Cycloheptadienyl tricarbonyliron, carbene derivatives of ; Cycloheptatrienyl, carbene derivatives of ; Enol ether, elimination from carbene complexes ; Spirocyclopropanes, elimination from carbene complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Organic Syntheses via Transition Metal Complexes, 71[1].  -  Methylcarbene Complexes of Chromium and Tungsten with Cycloheptatrienyl-, Cyclohexadienyl[Fe(CO)3]- and Cycloheptadienyl[Fe(CO)3] SubstituentsMethylcarbene complexes LnM=C(OEt)CH3 1 [LnM = (CO)5Cr, (CO)5W] react with tropylium tetrafluoroborate (2a) or coordinated olefins of [C6H7Fe(CO)3]BF4 (2c), [C7H9Fe-(CO)3]BF4 (2d), and [C7H7Fe2(CO)6]BF4 (2d) in the presence of Et3N to give complexes LnM=C(OEt)CH2R 3a-e and LnM=C(OEt)CHR2 7a-d by substitution of one or two α-hydrogen atoms. The trimetallic WFe2 carbene complexes 7c, d derived from 1b with 2c, d form three stereoisomers each, which are fully characterized spectroscopically, (R*,R*,S*)-7c additionally also by an X-ray structure analysis, Ligand elimination from 3 and 7 may involve a-and/or β-hydrogen transfer reactions: Thus enol ethers (Z/E)-6 are eliminated from α-monosubstituted methylcarbene complexes 3a, c, d in yields of 62-90% by a pyridine-induced transfer of an α-hydrogen to the carbene carbon atom; with increasing steric demand of R the elimination of the (Z) isomer (Z)-6 from 3 is favoured over the formation of the (E) isomer (E)-6. The enol ether 10 becomes a minor side product in the pyridine-induced ligand elimination from α-disubstituted complexes 7a, b. In these cases the spirocyclopropane 8 is formed as the main product (60-82%) besides the 4,5-homotropylidene 9 by a conformationally directed β-hydrogen transfer reaction.
    Additional Material: 1 Ill.
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  • 5
    ISSN: 0009-2940
    Keywords: 1,2-Dihydro-1,3,2λ5,4λ5-diazadiphosphete ; Isomerization ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1,2-Dihydro-1,3,2λ5,4λ5-diazadiphosphete - Synthesis, Structure and Isomerization to the „Inner Salt“ of 1,3,2,4λ5-Diazadiphosphetan-2-ium HydroxideThe photochemical reaction of the azidophosphane (iPr2N)2PN3 (1) with the tetraazaphospholene (3) and the bis(imino)phosphorane (Me3Si)2NP(=NSiMe3)2 (6) proceeds by elimination of N2 to yield (5) and by 1,3-silyl group shift to furnish (8) the structures of which were determined by means of NMR data and, in the case of 5, additionally by X-ray structure analysis.
    Additional Material: 1 Ill.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 127 (1994), S. 2475-2482 
    ISSN: 0009-2940
    Keywords: Vinylcarbene complexes ; Chromium complexes ; Tungsten complexes ; Phosphorus ylide complexes ; Alkynylcarbene complexes ; Allene complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Alkynylcarbene complexes (CO)5M≡C(OEt)-C≡C—R 1 (M = Cr, W; R = Ph, tBu, SiMe3) readily add tertiary phosphanes PPhR2′ 4 (R′ = Ph, Me) to form stable zwitterionic phosphonium allenide complexes (CO)5M--C(OEt) = C≡C(R)-P+PhR2′ 5. Complex 5a (M = Cr, R = R′ = Ph) was characterized by X-ray diffraction. The addition of secondary phosphanes PHR2 6 to 1 affords red (2-phosphanyl ethenyl)-carbene complexes (CO)5M≡C(OEt)-CH≡C(R)-PR2 (E)-8 (R = tBu, cC6H11, Ph) in 34-89% isolated yields. Dinuclear complexes (CO)5M≡C(OEt)-CH≡C(R)-P(R2)M(CO)5 (E)-9 are obtained as byproducts. Compounds (E)-8b (M = Cr, R = cC6H11) and (E)-9i (M = Cr, R = Ph) were characterized by X-ray analyses.
    Additional Material: 3 Ill.
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  • 7
    ISSN: 0044-2313
    Keywords: Aluminum sulfide ; crystal structure ; chemical transport ; five-coordinated aluminum ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Crystal Structure of a Novel Hexagonal Modification of Al2S3 with Five-coordinated AluminumA new hexagonal high temperature modification of Al2S3 could be prepared by chemical vapour transport with iodine (860 → 750°C) or by annealing of α -Al2S3 at 550°C. According to the single crystal X-ray structure determination the novel form of Al2S3 crystallizes in space group P 61 (No. 169) with a = 6.491(1), c = 17.169(4) Å, V = 626.5 Å3, Z = 6; R = 0.0253. In this modification one half of the aluminum atoms are tetrahedrally coordinated [d(Al—S): 2.226-2.267 Å], whereas the other half are in trigonal bipyramidal coordination of five S atoms with bond lengths of 2.272-2.315 Å (equatorial) and 2.495-2.521 Å (axial).Aluminum in AlS5 coordination is observed for the first time in this compound. The crystal structure is isotypic to In2Se3 and AlInS3. In addition, results of a refinement of the α -Al2S3 crystal structure are reported which were obtained on crystals prepared also by chemical vapour transport with iodine.
    Notes: Eine bisher noch nicht beschriebene hexagonale Hochtemperatur-Modifikation von Al2S3 konnte in reiner Form entweder durch chemischen Transport mit Iod (860 → 750°C) oder durch Tempern von α -Al2S3 oberhalb 550°C erhalten und durch eine Einkristall-Röntgenstrukturanalyse charakterisiert werden.Die neue Form des Al2S3 kristallisiert in der Raumgruppe P 61 (Nr. 169) mit a = 6,491(1), c = 17,169(4) Å, V = 626,5 Å3, Z = 6; R = 0,0253. In dieser Modifikation liegt die eine Hälfte der Aluminiumatome tetraedrisch koordiniert vor [d(Al—S): 2,226-2,267 Å], während die andere Hälfte trigonal-bipyramidal von fünf S-Atomen mit Al—S-Bindungslängen von 2,272 bis 2,315 Å (äquatorial) und 2,495-2,521 Å (axial) umgeben ist.Aluminium in AlS5-Koordination ist bisher unbekannt und wird hier zum ersten Mal beobachtet. Die Struktur ist isotyp zu In2Se3 und AlInS3. Zusätzlich wird über die Verfeinerung der Kristallstruktur α von -Al2S3 an Einkristallen berichtet, die ebenfalls durch chemischen Transport mit Iod hergestellt wurden.
    Additional Material: 2 Ill.
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  • 8
    ISSN: 0009-2940
    Keywords: Phosphaalkyne ; [3 + 2] Cycloaddition ; 1-Aza-3,4-diphospholenes ; Diphosphiranes ; 1-Aza-3,4-diphospholes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of the (diisopropylamino)phosphaethyne (1) with diazo compounds of the type R1R2C=N2 (2a-2c) unexpectedly leads in high yields (60-90%) to the 1-aza-3,4-diphospholene derivatives 3a-3c, a new class of heterocycles. NMR investigations of the analogous reaction of 1 with diazocyclopentadiene 2d show that the multi-step formation of 3a-3c proceeds via the 1-aza-3,4-diphospholes 6a-6d as intermediates.
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1243-1246 
    ISSN: 0044-2313
    Keywords: Octa(silasesquioxanes) ; hydrolytic polycondensation ; γ-bromopropylocta(silasesquioxane) ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Structures of γ-Halopropyl-octa(silasesquioxanes)As a more rapid and versatile synthetic approach, we have studied the FeCl3-catalyzed hydrolytic polycondensation of suited trichlorosilanes in a biphasic system which yields e.g. the new octa(silasesquioxane) (BrCH2CH2CH2)8Si8O12.
    Notes: Ein Verfahren zur FeCl3-katalysierten Hydrolyse von Trichlorsilanen im Zweiphasensystem wird untersucht und das dargestellte, neue Silasesquioxan (BrCH2CH2CH2)8Si8O12 isoliert und charakterisiert.
    Additional Material: 2 Ill.
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  • 10
    ISSN: 0044-2313
    Keywords: Phosphaalkyne, amino- ; nickel, platinum, cobalt complexes ; 1 λ3, 3 λ5-diphosphetene ; 1H, 13C{1H} and 31P{1H} NMR spectra ; X-ray structure determination ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactive E = C(pp)π-Systems. XLII [1]. Novel Coordination Compounds of 2-(Diisopropylamino)-1-phosphaethyne: [{η4-(iPr2NCP)2}Ni{η2-(iPr2NCP)}], [(Ph3P)2Pt{η2-(iPr2NCP)}], and [Co2(CO)6{η2-μ2-(iPr2NCP)}]2-(Diisopropylamino)-phosphaethyne iPr2N—C≡P (2) reacts with the Ni(0)-complexes [Ni(1,5-cyclooctadiene)2] and [Ni(CO)3(1-azabicyclo[2.2.2]octane)], respectively, to give the novel complex [{η4-(iPr2NCP)2}Ni{η2-(iPr2NCP)}] (5), with the 1,3-diphosphacyclobutadiene derivative and 2 (side-on) as π-ligands. The molecular structure of 5 determined by X-ray diffraction on single crystals proves the spin systems and rotational barriers deduced from NMR-data (1H, 13C-, 31P). The PC distances of the four-membered ring of 1.817(2) and 1.818(2) Å - as expected - are considerably longer than the PC bond of the η2-coordinated phosphaalkyne 2 [1.671(2) Å]. - In the reactions of 2 with [(Ph3P)2Pt(C2H4)] or [Co2(CO)8] the ligand properties of 2 resemble those of alkynes affording the complexes [(Ph3P)2Pt{η2-(iPr2NCP)}] (7) with side-on coordinated 2 and [Co2(CO)6{η2-μ2-(iPr2NCP)}] with 2 acting as a 4e donor bridge in quantitative yield.In attempts to prepare copper(I) complexes of the aminophosphaalkyne 2 by reaction with CuCl or CuI the only isolable product formed in reasonable amounts under the influence of air and moisture is the 1 λ3, 3 λ5-diphosphetene (iPr2N) (10) (isolated yield: ca. 20%). The crystal structure analysis of 10 indicates a strong structural relationship to the diamino-2-phosphaallyl cation [Me(iPr2N)]+ (12), the 1,3-diphosphacyclobutadiene ligand (iPr2NCP)2 in the binuclear complex [{η1, μ2-(iPr2NCP)2}Ni2(CO)6] (3a) as well as to the heterocycles (dme)2LiOE2′ (E′ = S, 11a; E′ = Se, 11b) prepared by Becker et al. [11b, 35].
    Notes: 2-(Diisopropylamino)-phosphaethin iPr2N-C≡P (2) reagiert mit den Ni(0)-Komplexen [Ni(1,5-Cyclooctadien)2] bzw. [Ni(CO)3(1-Azabicyclo[2.2.2]octan)] zu dem neuen Komplex [{η4-(iPr2NCP)2}Ni{η2-(iPr2NCP)}] (5), der zwei Moleküle 2 in Form des 1,3-Diphosphacyclobutadiensystems und ein Molekül 2 „side-on“ koordiniert als π-Liganden enthält. Die Molekülstruktur von 5, ermittelt durch Röntgenbeugung an Einkristallen, bestätigt die aus den NMR-Daten (1H-, 13C-, 31P) abgeleiteten Spinsysteme und Rotationsbarrieren. Die PC-Abstände des Vierrings sind mit 1,817(2) bzw. 1,818(2) Å erwartungsgemäß erheblich länger als die PC-Bindung des η2-koordinierten Phosphaalkins 2 [1,671(2) Å]. Bei den Umsetzungen von 2 mit [(Ph3P)2Pt(C2H4)] bzw. [Co2(CO)8] entspricht das koordinative Verhalten dem von Alkinen; sie liefern die Komplexe [(Ph3P)2Pt{η2-(iPr2NCP)}] (7) mit side-on gebundenem 2 bzw. [Co2(CO)6{η2-η2-(iPr2NCP)}] mit 2 als 4e-Donorbrücke in quantitativer Ausbeute.Bei dem Versuch, aus 2 und CuCl bzw. CuI Kupfer(I)-Komplexe des Aminophosphaalkins darzustellen, bildet sich unter Einwirkung von Luft und Feuchtigkeit als einziges isolierbares Produkt das 1λ3, 3λ5-Diphospheten (iPr2N) (10) in beträchtlicher Menge (Reinausbeute: ca. 20%). Für 10 ergibt sich aus der Kristallstrukturanalyse eine enge Beziehung zu dem Diamino-2-phosphaallyl-Kation [Me(iPr2N)]+ (12), dem 1,3-Diphosphacyclobutadien-Liganden (iPr2NCP)2 im Zweikernkomplex [{η1-μ2-(iPr2NCP)2}Ni2(CO)6] (3a) sowie zu den von Becker et al. [11 b, 35] dargestellten Heterocyclen (dme)2LiOE2′ (E′ = S, 11a; E′ = Se, 11b).
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