ISSN:
0009-2940
Schlagwort(e):
Reactions at coordinated cyanide
;
Cycloadditions, organometallic
;
Carbenoid heterocycles
;
Metal-ligand bond cleavage
;
Oxazolinone syntheses
;
Chemistry
;
Inorganic Chemistry
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
Chemistry of Hydrogen Isocyanide, 9[1]. - Three-Component Cycloadditions with Cyano ComplexesA novel and obviously general reaction of the coordinated cyano ligand in [M(CN)(CO)5] - (M = Cr, W) is reported, viz. its high-yield one-step [2 + 1 + 2] cycloaddition with a great variety of isocyanides and ketones resulting in carbenoid metal complexes of five-membered N,O heterocycles. The structure of the product 1a from [W(CN)(CO)5] - , tert-butyl isocyanide, and diethyl ketone has been elucidated by X-ray diffraction and found to contain a C-bound non-aromatic 4-aminooxazoline with an unprecedented π-delocalization along the exo chain which is also evident from severe low-field shifts of the C-2 and C-4 signals in the 13C-NMR spectra. The heterocycles are cleaved off the metal by oxidative decomposition with KMnO4/Fe(NO3)3 to give the corresponding oxazolinones, e.g. 4, with a high potential for biological activity. The general validity of this reactivity pattern for metal cyanides is further demonstrated by the successful incorporation of cyanoiron(II) and -cobalt(III) species in these three-component cycloaddition reactions.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/cber.19931261012
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