Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    ISSN: 1042-7163
    Keywords: Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The one-pot reaction of the alcohol adducts F3CP(H)CF2OR of perfluoro-2-phosphapropene with secondary amines in a 1:3 molar ratio affords the stable phosphaalkenes F3CP=C(OR)NR2 (R = Me, Et) 1-4 in yields of 58%. NMR and He(I) PE spectroscopic investigations show that the lone pair electrons on nitrogen and oxygen participate in n/π conjugation. In contrast to typical low-coordinated double bonds the new derivatives do not react with alcohols, amines, and 1,3-dienes. The derivatives are more closely related to the phosphaalkenes F3=C(F)NR2 than to perfluoro-2-phosphapropene. The reaction of F3=C(OEt)NMe2 (3) with Cr(CO)5THF yields the η1(P) complex Cr(CO)5[F3CP=C(OEt)NMe2] (7) with an unusually long sp2 PC bond (1.809 Å).
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 123 (1990), S. 2317-2320 
    ISSN: 0009-2940
    Keywords: Trifluoromethylphosphane/Phosphaalkenes, fluoro-/Phosphaalkyne, amino- ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactive E=C(p-p)π-Systems, XXVI.  -  Facile Synthesis of Phosphaalkenes of the Type HP=C(F)NR2 and the Phosphaalkyne P≡C-N(iPr)2The reaction of trifluoromethylphosphane CF3PH2 with secondary amines in a 1:3 molar ratio leads to the novel methylenephosphanes (phosphaalkenes) HP = C(F)NR2 [R = Me (1), Et (2), Pr (3), piperidine (4)] in yields between 40 and 60%. The analogous deuterium compound DP = C(F)NEt2 (5) is formed by the reaction of CF3PD2 with Et2ND. However, with di(isopropyl)amine the new phosphaalkyne P ≡ C—N(iPr)2 (6) is produced instead of the expected phosphaalkene.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 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.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 0009-2940
    Keywords: Ethaneselenol, pentafluoro-, IR, Raman, NMR, electron diffraction ; ab initio Calculation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactive E=C(p-p)π Systems, XXXVII[1]. - Pentafluoroethaneselenol: Synthesis, Spectra, and Gas-Phase StructureHerrn Professor Wolfgang Sawodny zum 60. Geburtstag gewidmet.Pentafluoroethaneselenol HSeC2F5 (1) and its deuterated analogue DSeC2F5 (2) are obtained in moderate yields by cleavage of the diselane (SeC2F5)2 with Me3SnH and Me3SnD, respectively. Complete characterization of the labile compounds was accomplished by spectroscopic investigations (IR, Raman, MS; 1H, 13C, 19F, 77Se NMR). The molecular structure was determined by electron diffraction in the gas phase together with ab initio calculations.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 0009-2940
    Keywords: λ3-Phosphaalkyne, 2-amino- ; PE Spectroscopy ; Calculations, ab initio ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactive E=C(p-p)π-Systems, XXXVIII.  -  Molecular and Electronic Structure of 2-(Diisopropylamino)-1λ3-phosphaethyne iPr2NC≡PThe molecular structure of 2-(diisopropylamino)-1λ3-phosphaethyne iPr2NC≡P (3) has been investigated by X-ray diffraction using a single crystal grown from the melt at -50.2°C. Bond distances and angles indicative for the electronic structure are: P°C 155.2(2), N—C(sp) 131.2(3) pm, P—C—N 179.2(2)°; with a sum of angles 359-8° the nitrogen atom has a trigonal-planar coordination. The reported geometrical parameters of 3 have been reproduced by ab initio calculations (3-21G and DZP basis), showing that the lengthening of the P°C and the shortening of the C—N bond can be rationalized by the interaction of the π system of the triple bond with the 2p orbital at N. The He(I) photoelectron spectrum of 3 confirms the strong interaction.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 0009-2940
    Keywords: Selenium ; Fluorine ; Amides ; Cleavage reactions ; Cycloadditions ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Bis(trifluoromethylketiminoalkyl)diselanes [SeC(=NR)CF3]2 (6) [R = Me (a), iPr (b), tBu (c)] have been prepared in high yields (55-70%) by reaction of the diselane (SeC2F5)2 (2) with RNH2. However, the analogous reaction of 2 with secondary amines, R2NH, results in the cleavage of the Se-Se bond and leads to the N,N-dialkyl-2,2,2-trifluoroselenoacetamides Se=C(NR2)CF3 (7) [R = Me (a), iPr (b)]. Cleavage of 6a-6c with Me3SnH affords the selenoamides Se=C(NHR)CF3 (9) and the corresponding stannylselanes Me3SnSeC(=NR)CF3 (10) [R = Me(a), iPr (b), tBu (c)]. Selenoamides 7 and 9 can also be prepared from pentafluoroethylselenol HSeC2F5 (3), Se=C(F)CF3, (1) or its polymer [SeC(F)CF3]n (4) and primary or secondary amines. N,N-dialkyl-2-methyl-3-fluoro-4,4,4-trifluoroselenoacrylamides Se=C(NR2)C(Me)=C(F)CF3[R = Et (13a), iPr (13b)] are prepared in moderate yields under mild conditions by treating either trifluoromethylselenocarbonyl fluoride (1) or its polymer [SeC(F)CF3]n with 1-dialkylamino-1-propynes. The reaction proceeds by [2 + 2] cycloaddition and stereospecific electrocyclic ring-opening, yielding, with respect to the resulting C=C double bond, the E isomer as the only product. The molecular structures of 7b, 9a and 13b show the typical features of selenoamides with C(Se)-N bond shortening and C-Se bond elongation due to π interaction of the N lone pair with the C=Se double bond. The observed perpendicular orientation of the selenoamide and the alkene units of 13b prevents π delocalization.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 121 (1988), S. 655-664 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactive E=C (p—p) π Systems, XIV.  -  Synthesis and Structure of Phosphaalkenes of the Type F3CP=C(F)NR2Perfluoro-2-phosphapropene 1reacts quantitatively with secondary amines R2NH in the molar ratio of 1:2 at temperatures between -120 and -40°C to give (trifluoromethyl)phosphaalkenes of the type F3CP=C(F)NR2 R = Me (2), Et (3), i-pr (4); NR2 = pyrrolidino (5), piperidino (6), 2-methylpiperidino (7, 3-methylpiperidino (8), N-methylanilino (9). Diphenylamine does not react in the same way even at room temperature. The same products are obtained by teh reaction of (CF3)2PH with R2NH and R2NH/NEt3, respectively, in molar rations of 1:3 or 1:1:2. The new compounds 4-9 just as 2 and 3 are stable at room temperature and without exception have Z configuration. The X-ray structure analysis of 1-(dimethylamino)- 1,3,3,3-tetrafluoro-2-phospha-1propene (2) proves the participation of the lone pair on nitrogen in stabilizing the system. The lattice of 2 contains C4H6F4NP molecules with an almost planar CP=C(F)NC2 skeleton. The PC bond distance amounts 1.744(2) Å, the CN bond [1.311(2)Å] is 0.16Å shorter than CN single bonds in amines suggesting a bond order near 2. The reaction of 2With Cr(CO)5(THF) yields the complex Cr(CO)5[F3CP=C(F)NMe2] (10) with P-coordination. In the crystal structure of 10 the CN distance of the coordination. In teh crystal structure of 10 the CN distance of the coordinated ligand is somewhat smaller (1.29 Å) and is slowly transformed to give 2 and the binuclear complex [Cr(CO)5]2F3CP=C(F)NMe2 (11)
    Notes: Perfluor-2-phosphapropen 1reagiert mit sekundären Aminen R2NH im Molverhältnis 1:2 bei Temperaturen zwischen -120 und -40°C quantitativ zu (Trifluormethyl) phosphaalkenen des typs F3CP=C(F)NR2 [R = me(2), Et (3), i-Pr (4); NR2 = Pyrrolidino (5), Piperidino (6), 2-methylpiperidino (7), 3-Methylpiperidino (8), N-Methylanilino (9)]. diphenylamin Setzt sich selbst bei Raumtemperatur nicht in analoger Weise um. Zu den Gleichen Produkten gelangt man durch Umsetzung von (CF3)2PH mit R2NH bzw. R2NH/NEt3 im Molverhältnis 1:3 bzw. 1:1 bzw. 1:1:2. Die neuen Verbindungen 4-9 sind wie 2 und 3 bei Raumtemperatur beständig and besitzen ausnahmslos die Z-Konfiguration. Die Röntgenbeugungsanalyse des 1-(Dimethylamino)-1,3,3,3-tetrafluor-2-phospha-1-propens (2) beweist die beteiligung des freien Elektronenpaars am Stickstoff an der Stabilisierung des Systems. Das Gitter von 2. enthält C4H6F4NP-Moleküle mit fast planarem CP=C(F)NC2-Gerüst. Der PC-Bindungsabstand beträgt 1.744 (2) Å, der CN-Abstand ist mit 1.311(2)Å 0.16Å Kürzer als die CN Einfachbindungen in Aminen und zeigt eine Bindungsordnung nahe 2 an. Die Umsetzung von 2Mit Cr(CO)5(THF) liefert den Komplex CR(CO)5[F3PC=C(F)NMe2] (10) mit P-Koordination. IN der Kristallstruktur von 10ist der CN-abstand des Koordinierten Liganden Geringfügig über (1.29 Å), der PC-Abstand deutlich gröβer (1.80Å) als in 2.10 wandelt sich bei 25°C unter Freisetzung von 2 langsam in den Zweikernkomplex [cr(CO)5]2F3CP=C(F)NMe2 (11) um.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 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.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...