Library

X
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
    Electronic Resource
    Electronic Resource
    Organische Synthesen mit Übergangsmetall-Komplexen, 64[1]. 1,4-Diaminonaphthaline über Ketenimin-Komplexe aus (β-Aminovinylcarben)chrom-Komplexen und Isocyaniden (1993)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 126 (1993), S. 1867-1872 
    Details
    ISSN: 0009-2940
    Keywords: Aminobenzannulation with isocyanides ; 1,4-Diaminonaphthalines ; Alkynylcarbene complexes ; β-Aminovinylcarbene complexes ; Dienylketenimine complexes ; 4-Amino-1-chroma-1,3-dienes ; Chromium complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Organic Syntheses via Transition Metal Complexes, 64[1]. - 1,4-Diaminonaphthalines via Ketenimine Complexes from (β-Aminovinylcarbene)chromium Complexes and IsocyanidesThe thermal reaction of (dienylcarbene)chromium complexes (= 1-chroma-1,3,5-trienes) with isocyanides provides a mild and regiospecific access to aromatic amines. Thus, 1,4-diamino-2-ethoxynaphthalines 6a-d [1-NHc-C6H11; 4-NRR1 = NMe2 (a) (S)-2-hydroxymethylpyrrolidinyl (b) (1R,2S)-2-methylamino-1-phenyl-1-propanol (c), NtBuMe (d)] are obtained by the cyclization of (E)-(β-aminostyrylcarbene)chromium complexes (CO)5Cr=C(OEt)CH=C(NRR1)C6H5 [(E)-3a-d] with cyclohexyl isocyanide (4) at 90°C in 72-85%. The aminocarbene complexes (E)-3a-d are accessible with high stereoselectivity [〉95% (E) configuration] and chemical yields of 91-96% by the addition of secondary amines HNRR1 2a-d to the (1-alkoxy-3-phenylpropynylidene)chromium complex (CO)5Cr=C(OEt)C≡CC6H5 (1). 3 and 4 give initially mono- and bis(isocyanide) complexes, e.g. (E)-8a and (E)-9a, and subsequently dienylketenimine complexes by the insertion of 4 into the M=C bond of 3. Dienylketenimine complexes are key intermediates in the formation of 6.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19931260818
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Organische Synthesen mit Übergangsmetallkomplexen, 70. [2-(Galactopyranosylamino)ethenyl]carben- und 3-(Galactopyranosylamino)-1,2-propadienyliden-Komplexe durch 3-Addition von 2,3,4,6-Tetra-O-pivaloyl-β-D-galactopyranosylamin an Alkinylcarben-Komplexe (M = Cr, W).  -  Atropisomere Galactopyranosyl-Pyrrole durch Reaktion von [2-(Galactopyranosylamino)ethenyl]carben-Komplexen mit Isocyaniden (1994)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 127 (1994), S. 725-729 
    Details
    ISSN: 0009-2940
    Keywords: [2-(Amino)ethenyl]carbene complexes ; 3-Amino-1,2-propadienylidene complexes ; (2,3,4,6-Tetra-O-pivaloyl-β-D-galactopyranosylamine, carbene complexes of ; Ketene imines ; Isocyanides ; Pyrroles ; Alkynylcarbene complexes of chromium and tungsten ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Organic Syntheses via Transition Metal Complexes, 70[1].  -  [2-(Galactopyranosylamino)ethenyl]carbene and 3-(Galactopyranosylamino)-1,2-propadienylidene Complexes on 3-Addition of 2,3,4,6-Tetra-O-pivaloyl-β-D-galactopyranosylamine to Alkynylcarbene Complexes (M = Cr, W).  -  Atropisomeric Galactopyranosyl Pyrroles by Reaction of [2-(Galactopyranosyl-amino)ethenyl]carbene Complexes with IsocyanidesEnantiomeric pure (2-aminoethenyl)carbene complexes LnM=C(OEt)—CH=C(Ph)NHR* (Z)-3 and 3-amino-1,2-propadienylidene complexes LnM=C=C=C(Ph)NHR* 4 [R* = 2,3,4,6-tetra-O-pivaloyl-β-D-galactopyranosyl] are obtained by the addition of galactopyranosylamine R*-NH2 2 to the corresponding alkynylcarbene complexes LnM=C(OEt)—C≡CPh 1 [LnM = (CO)5Cr, (CO)5W]. Treatment of (Z)-3 with two equivalents of tert-butyl isocyanide (5) affords isocyanide complexes 6 and ketene imines 7. The latter cyclize spontaneously to give galactopyranosylpyrroles 8 which form stable atropisomers 8A and 8B.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19941270423
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Organic Syntheses via Transition Metal Complexes, 74[1] Novel Phosphonium Allenide and 2-Phosphanylethenyl Carbene Chromium and Tungsten Complexes (1994)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 127 (1994), S. 2475-2482 
    Details
    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.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19941271218
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Mesoionic Pyrrolium Complexes and Dihydropyrroles by Cycloaddition of (Non-enolizable) Imines to an [(1-Alkynyl)carbene]tungsten Complex (1998)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 1998 (1998), S. 1623-1629 
    Details
    ISSN: 1434-1948
    Keywords: (1-Alkynyl)carbene complexes ; Pyrroles ; Imines ; Mesoionic compounds ; Tungsten complexes ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reaction of the [(1-alkynyl)carbene]tungsten complex (CO)5W=C(OEt)C≡CPh (1a) with non-enolizable imines, e.g. 9-fluorenone imines 2 [NR = N(iPr), N(c-C6H11)], affords novel mesoionic pyrrolium carbonyltungstates 3 (by [3+2] cycloaddition) together with dihydropyrroles 4 (by dichotomy of the C=N bond and subsequent insertion of the carbene carbon atom into an NC-H bond). Cross-conjugated azametallatrienes 6 and pentacarbonyltungsten complexes 7 of the dihydropyrroles 4 have been identified to be precursors to compound 4. Compounds 3b, 4a, and 6a have been characterized by X-ray crystal structure analyses.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...