Synthese von Diaza-octahydroporphinato-kobalt (III)-Komplexen als Vitamin-B12-Modellverbindungen

Synthesis of Octahydro-porphinato-cobalt(III) Complexes as Vitamin B₁₂ Model Compounds The synthesis of (±)-dibromo[1-hydroxy-2,2,3,3,7,7,8,8,12,12,13,13,17,17,18,18-hexadecamethyl-10,20-diaza-octahydroporphinato]cobalt(III) (2a) is described. The dicyano complex 2b and the corresponding annulene complex 3 have been obtained by exchange of its axial ligands and by elimination of the hydroxy group, respectively.     

Synthese von natürlichen Haloindolen via Hetero-Cope-Umlagerung von Vinyl-N-phenylhydroxamaten

Synthesis of Natural, Halogenated Indoles via Hetero-Cope Rearrangement of Vinyl N-Phenylhydroxamates An efficient method for the synthesis of natural 4-chloro-6-methoxyindole (the promutagen from fava beans) and of the two 4,6- dibromo- and 3,4,6-tribromoindoles (produced by acorn worms, Enteropneusta) is presented. The key step is a hetero-Cope rearrangement of the intermediate N-phenyl-O-vinylhydroxylamine derivatives.