ZIB

Treffer pro Seite

Treffer 1 - 2 | 2 Treffer

Sortierung

Digitale Medien

New tetraaza macrocyclic complexes of palladium(II) and platinum(II) formed by the self-condensation of 5-amino-3-methyl-1-phenylpyrazole-4-carbaldehyde in the presence of metal ions. α-Amino ether and carbinolamine derivatives of the macrocyclic Schiff base metal complex (1998)

Ramadan, Abd El-Mottaleb M. ; El-Emary, Talaat I.

Springer

Transition metal chemistry 23 (1998), S. 491-495

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1572-901X

Quelle: Springer Online Journal Archives 1860-2000

Thema: Chemie und Pharmazie

Notizen: Abstract The self-condensation of 5-amino-3-methyl-1-phenylpyrazole-4-carbaldehyde (AMPC) in the presence of PdII and PtII ions yields the PdII and PtII complexes, [M(TAAP)]Cl2, of the fully cyclized tetradentate macrocyclic ligand tetrapyrazolo[1,5,9,13]tetraazacyclohexadecine, (TAAP). Metathetical displacement of the chloride has led to isolation a series of complexes of the type [M(TAAP)]X2, (X=I, ClO4 and BF4), the formulation of which is supported by elemental analysis, molar conductance and magnetic susceptibility measurements, and i.r. and u.v.–vis. spectra. Spectroscopic and other analytical results reveal that the complexes have square-planar stereochemistry with four donor nitrogen atoms coordinated to the metal ion in a planar array. The reaction which produces this new cyclic ligand is assumed to include the metal ion acting as a template for the condensation. Thus the probable mechanistic implications for the coordination template hypothesis are discussed to explain the formation of these new macrocyclic chelate compounds. Both PdII and PtII complexes appear to be sensitive to nucleophilic attack at the methine carbon, which is reversible upon acidification. The reaction of [Pt(TAAP)]2+ or [Pd(TAAP)]2+ with MeO- or EtO- ions results in the formation of partially solvolysed inner complexes containing two ionized α-amino ether functions, stabilized by the macrocyclic chelate ring. Attempts to prepare discrete α-carbinolamine derivatives were unsuccessful.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1023/A:1006988529965

Permalink

Bibliothek	Standort	Signatur	Band/Heft/Jahr	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

Digitale Medien

Thermolysis of 3-phenyl-5-arylamino-1,2,4-oxadiazole and thiadiazole derivativesPresented in The First International Conference on Basic Sciences and Advanced Technology, November 9-12, 1996 Assiut, Egypt. (1997)

Gaber, Abd El-Aal M. ; El-Emary, Talaat I. ; Atalla, Ahmed A.

New York, NY [u.a.] : Wiley-Blackwell

Heteroatom Chemistry 8 (1997), S. 287-291

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1042-7163

Schlagwort(e): Chemistry

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Chemie und Pharmazie

Notizen: Thermal reactions of 3-phenyl-5-arylamino-1,2,4-oxadiazoles I and II were investigated. Neat heating at ca. 250°C for 6 hours afforded H2O, benzonitrile, arylcyanamides, arylamines, azobenzene, benzimidazole derivatives, and 3,3′-diphenyl-5,5′-bis[1,2,4-oxadiazolyl]. Analogous results were obtained by the thermolysis of 3-phenyl-5-anilino-1,2,4-thiadiazole III at ca. 200°C for 2 hours. In addition to H2S, NH3, and HNCS, phenyl isothiocyanate and thiocarbanilide were obtained. Thermolysis of III in quinoline as a radical trap gave analogous resuLts but also 2-anilinoquinoline. A free-radical mechanism has been suggested to account for the identified products. © 1997 John Wiley & Sons, Inc.

Zusätzliches Material: 2 Tab.

Materialart: Digitale Medien

Permalink

Bibliothek	Standort	Signatur	Band/Heft/Jahr	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Treffer 1 - 2 | 2 Treffer