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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 113 (1980), S. 1549-1565 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Investigations in the System Iminophosphane/Diazoalkane: Iminomethylenephosphoranes and their Addition ProductsThe reaction of the fully silylated iminophosphane 1 with α-alkylated diazoethanes or -methanes gives iminomethylenephosphoranes 6 - 9, 12, 13. The ethylidenephosphorane 12 forms the cyclic diazadiphosphetidine 15 with accompanying migration of silyl groups, while in the presence of iminophosphane 1 an azadiphosphetidine 16 is obtained. The corresponding conversion of 1 with diazomethane leads, on the other hand, directly to the diphosphetane 19.  -  In contrast to 1, the imine-alkylated iminophosphane 20 reacts with 2-diazopropane with accompanying silyl group displacement to the iminomethylenephosphorane 21.  -  The influence of steric effects shows itself in the behaviour of these compounds in reactions with further diazoalkanes. Thus, the reaction of 18 with diazomethane, leads exclusively to the phosphirane 22, and of 6 mostly to the phosphirane 23, while using alkylated diazoalkanes instead yields 1:1-adducts from iminomethylene-phosphorane and diazoalkane (26, 27).  -  The spectroscopie data show that the influence of substituents can be understood as consequence of the polarisation effect of the ylidic bond system in the iminomethylenephosphoranes.
    Notes: Reaktion des vollständig silylierten Iminophosphans 1 mit α-alkylierten Diazoethanen bzw. -methanen ergibt die Iminomethylenphosphorane 6 - 9, 12, 13. Das Ethylidenphosphoran 12 cyclisiert unter Silylgruppenwanderung zum Diazadiphosphetidin 15, während in Gegenwart von Iminophosphan 1 ein Azadiphosphetidin 16 erhalten wird. Die entsprechende Umsetzung von 1 mit Diazomethan führt hingegen direkt zum Diphosphetan 19.  -  Im Gegensatz zu 1 reagiert das imin-alkylierte Iminophosphan 20 mit 2-Diazopropan unter Silylgruppenverschiebung zum Iminomethylenphosphoran 21.  -  Der Einfluß sterischer Effekte zeigt sich im Reaktionsverhalten dieser Verbindungen gegenüber weiterem Diazoalkan. So führt die Reaktion von 18 bzw. 6 mit Diazomethan ausschließlich bzw. überwiegend zum Phosphiran 22 bzw. 23, während mit alkylierten Diazoalkanen statt dessen 1:1-Addukte aus Iminomethylenphosphoran und Diazoalkan erhalten werden (26, 27).  -  Die spektroskopischen Daten zeigen, daß der Substituenteneinfluß als Folge eines Polarisationseffektes des ylidischen Bindungssystems in den Iminomethylenphosphoranen zu verstehen ist.
    Additional Material: 6 Tab.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 453-461 
    ISSN: 0009-2940
    Keywords: 1-Chloro-2,2,3-tris(trimethylsilyl)phosphirane ; Phosphirane derivatives ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Reactivity of a 1-Chloro-λ3-phosphirane[Bis(trimethylsilyl)methyl]dichlorophosphane (1) reacts with chlorobis(trimethylsilyl)methyllithium (2) to give 1-chloro-λ3-phosphirane 6. Nucleophilic substitution of the chlorine atom of 6 leads to a variety of derivatives 9a-n. In the case of bis(trimethylsilyl)amine the reaction does not provide the aminophosphirane 15 but to the isomeric phosphaalkene 16. However, 15 is accessible by reaction of the methylenphosphane 17 with 2. With an excess of nucleophile 9 is cleaved to give the phosphide 13 and tris(trimethylsilyl)ethene (10). Phosphirane 9f dissociates thermically to give 10 and chloromethylenephosphane 20. Reaction of 6 with methylenetriphenylphosphorane and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) leads to substitution with formation of 22, 23 while with trimethylsilyl azide the product is an azidophosphirane 24. 1-Chlorophosphirane 6 reacts with AlCl3 to give the phosphirane complex 27. The molecular structure of 27 as well as the NMR data of the phosphiranes are discussed.
    Notes: [Bis(trimethylsilyl)methyl]dichlorphosphan (1) reagiert mit Chlorbis(trimethylsilyl)methyllithium (2) zu dem 1-Chlor-λ3-phosphiran 6. Durch nucleophile Substitution des Chloratoms läßt sich 6 vielfältig derivatisieren (9a-n). Im Falle der Umsetzung mit Bis(trimethylsilyl)amin führt die Reaktion nicht zum Aminophosphiran 15, sondern zum isomeren Phosphaalken 16. Phosphiran 15 ist jedoch durch Reaktion des Methylenphosphans 17 mit 2 zugänglich. Durch Nucleophil im Überschuß wird 9 unter Abspaltung von Tris(trimethylsilyl)ethen (10) zum Phosphid 13 gespalten. 9f zerfällt thermisch unter Bildung von 10 und Chlormethylenphosphan 20. 1,8-Diazabicyclo[5.4.0]undec-7-en (DBU) und Methylentriphenylphosphoran reagieren mit 6 unter Substitution zu 22 und 23, während mit Trimethylsilylazid ein Azidophosphiran 24 erhalten wird. AlCl3 reagiert mit 6 zum Phosphiran-Komplex 27. Die Molekülstruktur von 27 und die NMR-Daten der Phosphirane werden diskutiert.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 123 (1990), S. 67-69 
    ISSN: 0009-2940
    Keywords: Diphosphabicyclobutanes / Valence isomerization ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: DiphosphabicyclobutanesTwo isomeric diphosphabicyclobutanes (5,11) are obtained by treatment of the phosphaalkenes X-P = C(Ph)Tms (1a) and X - P = CTms2 (1b) (X = halogen Tms = trimethylsilyl) with 2, Mg, or Na. Both syntheses proceed by coupling of two phosphaalkene units affording, however, two different diphospha-butadiene intermediates. 4 and 10 readily undergo isomerization reactions to form the diphosphabicyclobutanes. Irradiation of the phosphaalkenes Cp* - P = C(Ph)Tms (12a) and Cp* - P = CTms2 (12b) (Cp* = C5Me5) gives rise to a different reaction pathway. Dimerization of 12a, followed by homolytic cleavage of the Cp* - phosphorus bond and intramolecular recombination produces the butterfly compound 5, whereas homolytic cleavage of the Cp* - element bond in 12 b, followed by rearrangement and intermolecular recombination, affords the diphosphabicyclobutane 11.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 13-16 
    ISSN: 0009-2940
    Keywords: Diphosphines, tetrakis(diisopropylamino) ; Phosphinous anhydrides ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Structure of Bis[bis(diisopropylamino)phosphino]chalcogenidesPhosphorodiamidous chalcogeno-anhydrides [(R2N)2P]2X (R = Me2CH; X = S, Se, Te) (2a-c) have been obtained by insertion of elemental sulfur, selenium, or tellurium into the P-P bond of the corresponding diphosphane (1). The structure of 2a and 2c has been confirmed by an X-ray diffraction.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 1973-1976 
    ISSN: 0009-2940
    Keywords: 2-Phosphonioallene ligands ; Metallobis(methylene)phosphoranes ; Nickel complexes ; Platinum complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Structure of 2-Phosphonioallene ComplexesThe reaction of the chlorobis(methylene)phosphorane 1 with reactive olefin complexes of nickel and platinium affords the 2-phosphonioallene complexes 4b and 6a,b. The structure of this new class of three-electron donor ligands, involving a lowcoordinated phosphorus (V) cation, has been elucidated by NMR spectroscopy and a single-crystal X-ray study of 6a. The reaction proceeds via a metallobis(methylene)phosphorane intermediate, which could be isolated in the case of the (Et3P)2Pt complex 3a.
    Additional Material: 1 Ill.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 321-330 
    ISSN: 0009-2940
    Keywords: Phosphanes, (Z)-amino(imino)- ; 1,3,5-Triaza-2,4-diphospha-1,4-pentadienes, transition metal complexes of, dynamic behavior of ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: On the Knowledge of the 1,3,5-Triaza-2,4-diphospha-1,4-pentadienesHerrn Professor Heinrich Puff zum 70. Geburtstag gewidmetNucleophilic substitution reactions of the chloro(arylimino)-phosphane 1 yield the NH-functional amino(imino)phosphanes Mes*NPNHR (R = Mes, Ad, CPh3) 2d - f. Upon further reaction with 1 they are converted into the 1,3,5-triaza-2,4-diphospha-1,4-pentadienes Mes*NPN(R)PNMes* (R = Mes, Ad) 4d, e and Mes*NPN(Mes*)PNCPh3 5. According to crystal structure determinations all compounds 4a, d, e, 5 exhibit S conformation in the solid state. In addition to the “exo-endo” arrangement of the substituents (4a, 5) in the case of 4d, e the “endo-endo” conformation is observed for the first time. In solution, 4d, e and 5 are subject to dynamic rearrangements, whose mechanism is proven by NMR studies of partially 15N-enriched samples. The reaction of 4a with NorM(CO)4 (M = Cr, Mo) or Ni(CO)4 yields the metallaazadiphosphetidine complexes 6a - c Mes*NPN(tBu)PNMes*M(CO)n [M(CO)n = Cr(CO)4, Mo(CO)4, Ni(CO)2]. The crystal structure of 6a (“exo-endo-W”) is described.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 127 (1994), S. 313-319 
    ISSN: 0009-2940
    Keywords: Phosphirene imines ; 1,2-Diphosphete diimines ; Isomerization ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Investigations of the System Phosphirene Imine/Iminophosphane - Insertion and Isomerization ReactionsTreatment of the iminophosphanes R1P=NR2 1 [R2 = tBu, R1 = Et3C (a); R2 = Aryl, R1 = Et (b), Me (c)] with 1,4-diphenyl-butadiyne (2) leads to the phosphirene imines R1-(R2N=)P̌(Ph)=CCCPh 3a-c and [R1(R2N=)P̌(Ph)=CC]2 4a-c. Further reaction with 1a, c gives the 1,2-diphosphetes R1(R2N=)PP(R1)(=NR2)C(Ph)=CCCPh 5a, b, which isomerize in the case of R1 = Me into the triphosphabicyclo[3.2.0]-hepta-1,6-diene 7. In the reaction of the phosphirene imines R1(ArylN=)P̌(R2)=C(R2) 3 [R1 = Me, R2 = Ph (d); R1 = Et, R2 = COOMe (e)] with the iminophosphanes 1b, d the initially formed diphosphetes 9a, b isomerize to the 1,2-diazaphosphole Cl(Mes*N=)PN(Mes*)P(Me)C(Ph)=C(Ph) 10 or the dioxadiphosphabicyclooctadiene C=C(OMe)OP(=N-Mes*)(Et)C=C(OMe)OP(=NMes*)(Et) 12 depending on the substituents. A reaction of the phosphirene imine 3d with dimethylamino-borane furnishes the vinylphosphane. Ph(H)C=C(Ph)P(Et)N(H)Mes* (14) by ring opening. The compounds 7, 10, 12 have been characterized by X-ray structure analyses.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3227-3240 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: λ5-Di- and -Triazaphospholines - Synthesis, Isomerization, and DecompositionThe reaction of amino[(trimethylsilyl)methylene]thioxophosphorane 1 with diazoalkanes leads to Δ1-diazaphospholines 3, 7, 11, and 12. These sensitive compounds are stabilized by 1,3-migration of a trimethylsilyl group, where 3 and 7 end in the Δ2-diazaphospholines 4 and 8 and 11 and 12 decompose by [1 + 4]cycloreversion to give the azines 14 and 15 as well as aminothioxophosphane intermediate 13. 13 could be trapped by reaction with diazoalkanes as aminomethylenethioxophosphoranes (18 and 19). The corresponding phosphane system 20 and 21 is available by reduction of 18 and 19, respectively, with triphenylphosphane. tert-Butyl azide (22) and 1 form triazaphospholine 23, which isomerizes thermally by silyl migration to give 24. Photochemically induced elimination of N2 leads to the λ5-azaphosphiridine 25; this system is also accessible by reaction of aminoiminothioxophosphorane 26 with diazomethane. In contrast, thermal reaction of trimethylsilyl azide (30) and 1 results in a λ5-thiaphosphirane 31. Compounds of this type (31, 32) can also be synthesized by [1 + 2]cycloaddition of sulfur and the corresponding iminomethylenephosphorane. - The X-ray structure analysis of the Δ2-diazaphospholine 5 is described, NMR data and decomposition of di- and triazaphospholines are discussed.
    Notes: Amino[(trimethylsilyl)methylen]thioxophosphoran 1 reagiert mit Diazoalkanen zu den Δ1-Diazaphospholenen 3, 7, 11 und 12. Diese stabilisieren sich unter 1,3-Trimethylsilyl-Verschiebung zu den Δ2-Diazaphospholenen 4 und 8 bzw. zerfallen unter [1 + 4]-Cycloreversion zu Azin (14 und 15) und dem Aminothioxophosphan 13. 13 konnte durch Reaktion mit Diazoalkan als Aminomethylenthioxophosphoran (18 und 19) abgefangen werden. Durch Entschwefelung von 18 bzw. 19 mittels Triphenylphosphan ist das entsprechende Phosphan-System 20 bzw. 21 zugänglich. tert-Butylazid (22) reagiert mit 1 zum Triazaphospholen 23, das thermisch unter Trimethylsilyl-Wanderung zu 24 isomerisiert und photochemisch unter N2-Eliminierung das λ5-Phosphiridin 25 liefert, ein Verbindungssystem, das ebenfalls durch Umsetzung eines Aminoiminothioxophosphorans (26) mit Diazomethan zugänglich ist. Bei der thermischen Reaktion von 1 und Trimethylsilylazid (30) wird hingegen das λ5-Thiaphosphiran 31 erhalten. Verbindungen dieses Typs (31, 32) sind auch durch Schwefelung der entsprechenden Iminomethylenphosphorane zugänglich. - Die Röntgenstrukturanalyse des durch partielle Hydrolyse von 4 erhaltenen Δ2-Diazaphospholens 5 wird angegeben, und die NMR-Daten sowie der Zerfall der Di- und Triazaphospholene werden diskutiert.
    Additional Material: 5 Tab.
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 123 (1990), S. 169-176 
    ISSN: 0009-2940
    Keywords: Caesium effect / Chiroptical properties / Circular dichroism / Cyclophanes, multilayered ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Chiral Triple-Layered and Condensed [2.2]Cyclophanes - Synthesis, Structure, Chiroptical PropertiesThe helical title compounds 1-5 are obtained using a simple one-step cyclisation reaction with yields reaching or increasing those obtained by application of organometallic methods in [2.2]phane syntheses. The formation of the triple-layered phanes 1 leads with high selectivity only to the “up-down” isomers with fixed conformation, as shown by X-ray crystallography and by the detection of strong NOEs of the inner hydrogen atoms. For studies on structure-chiroptic relation-ships a systematic sequence of helical [2.2]phanes with larger arene systems is synthesized. Enrichment of enantiomers is achieved by HPLC on (+)-PTrMA; the kinetics of racemisation and the CD spectra are discussed.
    Additional Material: 5 Ill.
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 765-767 
    ISSN: 0009-2940
    Keywords: Phosphinediyl transfer reactions ; Azaphosphaboriridines ; Azadiphosphiridines ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Azaphosphaboriridines and Azadiphosphiridines by Phosphinediyl Transfer ReactionsThe azaphosphaboriridines (4a - d) are obtained by the reaction of the corresponding chloro(trimethyl-silyl)posphines RP(Cl)SiMe3 (1a - d) with the iminoborane 2. Equally, reaction of 1a - c with the iminophosphine 5 leads to the azadiphosphiridines (8a - c) via an imino-λ3,λ5-diphosphene intermediate tBuN=P(CEt3)=PCH-(SiMe3)2 (7a).
    Type of Medium: Electronic Resource
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