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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 113 (1980), S. 1566-1574 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Structure and Reactions of the Phosphinic Ester Me2P(:O)OC(CF3)2C(CF3)2OHThe product obtained from the reaction of the Me3SiO-functional 1,3,2λ5-dioxaphospholane 1 with water or hydrogen chloride has the structure 2b of a phosphinate; the expected isomeric hydroxyphosphorane 2a has not been observed. The structure of 2b has been determined by X-ray crystal structure analysis. Crystals of 2b are monoclinic; space group P21/c. In the crystalline state 2b forms dimers, as a result of strong hydrogen bonding between the P(:O)-group of one molecule and the OH-group of a second molecule. Reactions of 2b with chlorotrimethylsilane in the presence of triethylamine resulted in cyclisation with formation of the phosphorane 1. With thionyl chloride 2b gave the cyclic chlorophosphorane 3, while 2b and 3 reacted with formation of the cyclic anhydride 4 of the hypothetical hydroxyphosphorane 2a.
    Notes: Das Produkt der Umsetzung des Me3SiO-funktionellen 1,3,2λ5-Dioxaphospholans 1 mit Wasser oder Chlorwasserstoff besitzt die Konstitution 2b eines Phosphinsäureesters; das erwartete isomere Hydroxyphosphoran 2a wird nicht beobachtet. Die Struktur von 2b wurde durch Röntgen-analyse bestimmt. 2b kristallisiert monoklin, Raumgruppe P21/c, und bildet im kristallinen Zu-stand Dimere, in denen starke Wasserstoffbrückenbindungen zwischen der P(:O)-Gruppe eines Moleküls und der OH-Gruppe eines zweiten Moleküls vorliegen. Durch Umsetzung von 2b mit Chlortrimethylsilan in Gegenwart von Triethylamin erfolgt Cyclisierung zum Phosphoran 1. Umsetzung von 2b mit Thionylchlorid liefert das cyclische Chlorphosphoran 3, während aus 2b mit 3 das Anhydrid 4 des hypothetischen Hydroxyphosphorans 2a gebildet wird.
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  • 2
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Bis(trimethylsilyl)phosphates of 1,1,1,4,4,4-Hexafluoro-2,3-bis(trifluoromethyl)-2,3-butanediol and 1,1,1,3,3-Pentafluoro-2-propenolThe monocyclic phosphorane (EtO)3P[OC(CF3)2C(CF3)2O] 1 was hydrolized to give a mixture of an acyclic and a cyclic phosphate, 3 and 4.The trihydroxyphosphorane 2 could not be obtained. Iodotrimethylsilane 6 converts 1 into the silylated derivative of 4 which was found also besides (Me3SiO)2P(O)OC(CF3)2C(CF3)2OSiMe3 8 in the reaction of 3 and 4 with Me3SiCl/(Me3Si)2NH. (Me3SiO)3P 10 and hexafluoroacetone did not yield the tris(trimethylsiloxy)phosphorane 5, but the phosphonate 11 which gave (Me3SiO)2P(O)OC(CF3) — CF2 12 upon heating with the loss of fluorotrimethylsilane.
    Notes: Das monozyklische Phosphoran (EtO)3P[OC(CF3)2C(CF3)2O] 1 hydrolysierte zu einem Gemisch zweier Phosphorsäureester, einem azyklischen 3 und einem zyklischer 4, ohne daß das Trihydroxyphosphoran 2 erhalten werden konnte.Iodtrimethylsilan 6 überführte 1 in das silylierte Derivat von 4, welches neben (Me3SiO)2P(O)OC(CF3)2OSiMe3 8 auch bei der Umsetzung von 3 und 4 mit Me3SiCl/(Me3Si)2NH entstand. Die Reaktion von (Me3SiO)3P 10 mit Hexafluoraceton ergab kein Tris(trimethylsiloxy)-phosphoran 5, sondern den Phosphonsäureester 11, der beim Erhitzen unter Fluortrimethylsilanabspaltung in (Me3SiO)2P(O)OC(CF3) — CF2 12 überging.
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 2380-2388 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On 2-tert-Butyl-l,3,2λ5-dioxaphospholanes and 2-tert-Butyl-1,2λ5-oxaphosphetanesOxidative addition of hexafluoroacetone to the phosphorus(III) compounds 1c-g furnished the 1,3,2λ5-dioxaphospholanes 2c, 2d, 2f, 2g, and the 1,2λ5-oxaphosphetane 3, respectively; 2d undergoes thermal rearrangement to the corresponding l,2λ5-oxaphosphetane 4. The phospholes 5 and 6 are formed from hexafluorobiacetyl with phosphinous acid esters. 19F NMR spectroscopy was employed to investigate dynamic effects in the compounds obtained. For the phosphorane 2 c magnetic nonequivalence of the CF3 groups of the dioxaphospholane ring system as well as of those of the (CF3)2CHO group was observed. The related compounds 7-9 were studied for comparison, and the influence of the bulky tert-butyl groups at phosphorus was investigated.
    Notes: Durch oxidative Addition von Hexafluoraceton an die Phosphor(III)-Verbindungen 1c-g werden die 1,3,2λ5-Dioxaphospholane 2c, 2d, 2f und 2g bzw. das 1,2λ5-Oxaphosphetan 3 gebildet; 2d lagert sich thermisch in das entsprechende 1,2λ5-Oxaphosphetan 4 um. Die Phosphole 5 und 6 entstehen aus Hexafluorbiacetyl und Phosphinigsäureestern. Mit Hilfe der 19 F-NMR-Spektroskopie wurden dynamische Effekte untersucht. Bei dem Phosphoran 2c tritt magnetische Nichtäquivalenz sowohl der CF3-Gruppen des Dioxaphospholan-Ringsystems als auch der des (CF3)2CHO-Restes auf. Die analogen Verbindungen 7-9 wurden zur vergleichenden Betrachtung herangezogen und der Einfluß der raumerfüllenden tert-Butylgruppe am Phosphor studiert.
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  • 4
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Chemistry of 4-Chloro-1,3,5,7-tetramethyl-1,3,5,7-tetraaza-4λ5-phosphaspiro[3.3]heptane-2,6-dione; Crystal and Molecular Structure of a Chlorotetraaza-and of Two PentaazaphosphoranesThe reaction of the chlorophosphorane, 4-Chlor-1,3,5,7-tetramethyl-1,3,5,7-tetraaza-4λ5-phosphaspiro[3.3]heptan-2,6-dione (1) with methanol or phenol/triethylamine, trimethylsilyl thioethers, (dimethylamino)trimethylsilane, and sodium azide has furnished a series of N,N′-dimethylurea-substituted phosphoranes, 2-7, involving the above ring system. The azide group of 7 was found to react with trimethylphosphane in a Staudinger-type reaction to give the novel, mixed-valence diphosphorus compound 8 with the λ5P—N=P(λ4) grouping. The new compounds were characterized by analysis, NMR and IR spectra as well as by their mass spectra. - X-ray crystal structural analyses have been performed for the compounds 1, 6, and 7. In all cases a strongly distorted, trigonal-bipyramidal framework was found. Significantly different equatorial P—N bond lengths have been observed for 6 (164.4 pm) and 7 (169.8 pm), and for P—N(urea) (166.8-169.1 pm). For all three compounds, 1, 6, and 7, the axial P—N bond lengths are near 176 pm.
    Notes: Durch Umsetzung des Chlorphosphorans 4-Chlor-1,3,5,7-tetramethyl-1,3,5,7-tetraaza-4λ5-phosphaspiro[3.3]heptan-2,6-dion (1) mit Methanol bzw. Phenol/Triethylamin, Trimethylsilylthioethern, (Dimethylamino)trimethylsilan und Natriumazid wurde eine Reihe von N,N′-Dimethylharnstoff-substituierten Phosphoranen, 2-7, mit dem oben genannten Ringsystem dargestellt. Die Azidgruppe in 7 reagierte mit Trimethylphosphan im Sinne einer Staudinger-Reaktion unter Bildung der neuartigen gemischtvalenten Diphosphorverbindung 8 mit dem λ5P—N=P(λ4)-Strukturelement. Die neuen Verbindungen wurden analytisch, NMR-und IR-spektroskopisch sowie durch ihre Massenspektren charakterisiert. - Für die Verbindungen 1, 6 und 7 wurden Röntgenstrukturanalysen durchgeführt. In allen Fällen liegt ein stark verzerrtes, trigonal-bipyramidales Gerüst vor. Signifikant unterschiedliche äquatoriale P—N-Bindungslängen wurden für 6 (164.4 pm) und 7 (169.8 pm) beobachtet. Für die äquatorialen P-N(Harnstoff)-Bindungen wurden Werte von 166.8 bis 169.1 pm, für alle drei Verbindungen, 1, 6 und 7, axiale P—N-Bindungslängen um 176 pm gefunden.
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 123 (1990), S. 1307-1312 
    ISSN: 0009-2940
    Keywords: 1,3,2-Diazaphosphetidin-4-one derivatives ; Urea, phosphorylated ; P-Oxides ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Compounds Involving the 1,3-Dimethyl-1.3,2-diazaphosphetidin-4-one Framework Synthesis of 1,3-Dimethyl-1.3,2-diazaphosphetidin-4-one 2-Oxide DerivativesThe oxidation of 1,3,2-diazaphosphetidinones 3, 4, 7-9 to the respective P-oxides using NO2 (3→5 and 4→6) or (Me3SiO)2 (7→10, 8→11, and 9→12) is described. Other diazaphosphetidinone P-oxides 13-15 are obtained by the reaction of N,N′-dimethylurea with phosphonic dichlorides in the presence of triethylamine as an HCl acceptor. The compounds 5, 6, 10 - 15 contain the novel structural element, involving λ4P. The reaction of 10 and 15 with methanol leads to the formation of the acyclic methyl esters MeOP-(=O)(Y)N(Me)C(=O)N(Me)H (20) [Y = N(CH2)4] and (21) [Y = Ph].
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 123 (1990), S. 1759-1766 
    ISSN: 0009-2940
    Keywords: λ4-Phosphorus(V) compounds ; Donor-acceptor interactions, intramolecular ; N,N,N′-Trimethylethylenediamine, phosphorus(V) derivatives ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Intramolecular Donor-Acceptor Interactions in λ4P(V) Compounds.  -  Phosphorus(V) Derivatives of N,N,N′-Trimethyl-ethylenediamineThe chlorophosphino derivative of N,N,N′-trimethylethyl-enediamine Me2NCH2CH2(Me)NP(Cl)Me (1) and the 2-(diethylamino)-λ3-phospholidinium salt [Me2NEt2]+ Cl- (5) have been allowed to react with several oxidizing agents. Reaction of 1 with dimethyl sulfoxide furnishes the phosphonamidic chloride Me2NCH2CH2(Me)NP(=O)(Cl)Me (3) while with elemental sulfur the phosphonamidothioic chloride Me2NCH2CH2(Me)NP(=S)(Cl)Me (2) is obtained. The reaction of 2 with sodium tetraphenylborate furnished the 1,1,2,3-tetramethyl-1,3,2-λ4-diazaphospholidinium tetraphenylborate [Me2(=S)Me]+ [BPh4]- (4). The reaction of 5 with phenyl azide, followed by sodium tetraphenylborate led to 2-(diethylamino)-2-(phenylimino)-1,3,2λ4-diazaphospholidinium tetraphenylborate [Me2(=NPh)NEt2]+ [BPh4]-1 (7). The methoxy-λ3-diazaphospholidinium salt [Me2OMe]+ [BPh4]- (6) does not react with phenyl azide to produce the 2-methoxy-2-(phenylimino)-1,3,2λ4-diaza-phospholidinium salt analogous to 7; instead its rearrangement product, the dimeric 1,3,2λ4,4λ4-diazadiphosphetidine tetraphenylborate [Me3NCH2CH2(Me)NP(=O)NPh]22+2[BPh4]- (8), is isolated in low yield. Singlecrystal X-ray structure determinations of 4 and 8 are described.
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  • 7
    ISSN: 0009-2940
    Keywords: Fluorophosphoranes ; Donor-acceptor interaction ; Azonium salts ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of the tetrafluorophosphoranes RPF4 [R = CH3, C6H5, C6F5, (CH3)3SiCH2, and 2,5-(CH3)2C6H3] with N,N,Ń-trimethyl-N′-(trimethylsilyl))ethylenediamine (1) yields the corresponding triflurophosphoranes 2-6 by cleavage of the Si - N bond and elimination of (CH3)3SiF. In an analogous reaction the difluorophosphoranes R1R2PF2N(CH3)CH2CJ2N-(CH3)2 (R1 = R2 = C6H5, 7: R1 = C6H5, R2 = C4H4N, 8) are formed. Some of these N,N,Ń-trimethylethylenediamine-substituted di- and trifluorophosphoranes react with PF5 as a Lewis acid to form the corresponding azonium hexafluorophosphates 9-12 as a result of fluoride abstraction and intramolecular (CH3)2N→P donor-acceptor interaction. Compound 13 shows dynamic behaviour in solution. An exchange process is observed for the axial and equatorial fluorine atoms by 19F- and 31P-NMR spectroscopy. An X-ray structure analysis of the compounds 10 - 12 reveals the expected trigonal-bipyramidal geometry at phosphorus. The ethylenediamine ligand is found to form a chelate ring, whereby one axial and one equatorial site are bridged. The coordinative P - N bonds are very long (up to 207 pm).
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  • 8
    ISSN: 0009-2940
    Keywords: 2,4-Diaza-1,5-diphosphapentan-3-ones, 2,4-dimethyl- ; Coordination compounds ; Chromium complexes ; Molybdenum complexes ; Tungsten complexes ; Iron complexes ; Platinum complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Compounds with the 2,4-Dimethyl-2,4-diaza-1,5-diphosphapentan-3-one Skeleton; Synthesis, Structure, and Properties of 1,5-Di-tert-butyl-2,4-dimethyl-1,5-diphenyl-2,4-diaza-1,5-diphosphapentan-3-one and Its DerivativesN,N′-Dimethyl-N-N′-bis(trimethylsilyl)urea (1) reacts with tert-butylchlorophenylphosphane (2) to form the monophosphino/ trimethylsilyl-substituted urea 3. Under more vigorous conditions the bisphosphino-substituted derivative 4 was also obtained. The reaction of 4 with the tetracarbonyl norbornadiene derivatives of Cr, Mo, and W furnished the unusual chelate complexes 5-7, in which the ligand 4 is coordinated to the metal through one of the two phosphorus atoms and the oxygen atom of the carbonyl group. The free ligand 4 and the isostructural complexes 5 and 6 were subjected to X-ray structure analyses. The approximate twofold symmetry of 4 is lost as a result of a major conformational change on complex formation. In contrast, 4 reacts with Fe2(CO)9 and with (COD)-PtCl2 (COD=1,5-cyclooctadiene) to give the complexes 8 and 9. In both 8 and 9 the ligand 4 is coordinated by both phosphorus atoms. Reaction of 4 with sulfur and selenium led to the disulfide 10 and diselenide 11, whereas with tellurium no reaction was observed.
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 1325-1332 
    ISSN: 0009-2940
    Keywords: 1,5,2,4-Diazadiphosphorinan-6-one ; Tetrachloro-ortho-benzoquinone ; Oxidation ; Spirophosphorane ; Spirophosphorate ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The oxidation of 2,4-bis(diethylamino)-1,5-dimethyl-1,5,2,4-diazadiphosphorinan-6-one (1b) with two equivalents of tetrachloro-ortho-benzoquinone (TOB) (2) leads to the cleavage of the original heterocycle and to the formation of a mixture of compounds, including the 1,3,2-diazaphosphetidine 6 (“λ6P-”) and the spirophosphorane 7. Compound 7 exists as two isomers that undergo slow spontaneous transformation in solution to compound 9, containing a six-coordinate phosphorus atom. When the oxidation of 1b is carried out in two stages, with the second equivalent of TOB being added after an interval of four days, the cleavage of the original molecule does not occur, and compound 17, containing a seven-membered ring with two phosphorus atoms of opposite formal charge and different coordination number (“λ4P+,λ6P-”) is formed. The structures of 6, 7, 9, and 17 were established by low-temperature X-ray analysis. Compound 6 displays crystallographic twofold symmetry; the coordination at phosphorus is octahedral, but distorted by the phosphetidine ring. The phosphorus atom in 7 possesses square pyramidal coordination geometry, the pyramid base being defined by the four oxygen atoms. Compound 9 (“λ6P-”) crystallized with two molecules of CDCl3. Compound 17 crystallized as a dichloromethane solvate. Distorted octahedral and tetrahedral geometries were observed for P1 and P2, respectively. The four-membered ring is planar. The bridging hydroquinone ligand displays much wider O-C-C(-O) and C-O-P angles than the chelating hydroquinone.
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 126 (1993), S. 2379-2382 
    ISSN: 0009-2940
    Keywords: Steric overcrowding ; Trisphosphane, linear, bismethylene-bridged ; Molybdenum, complexes with bis- and trisphosphanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Bis[(di-tert-butylphosphanyl)methyl]methylphosphane[1]The synthesis of [(di-tert-butylphosphanyl)methyl]dimethyl-phosphane (3) and of the title compound 5 is described. 5 reacts with sulfur to form the trisulfide 6. Both 3 and 5 behave as bidentate ligands in forming the molybdenum complexes 8 and 10, which are characterized by single crystal X-ray structure determinations. 10 reacts with sulfur to yield the sulfide 11, which decomposes in solution within 6 h.
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