Expanding the Substrate Scope for C−H Amination Reactions: Oxidative Cyclization of Urea and Guanidine Derivatives
2006; American Chemical Society; Volume: 8; Issue: 6 Linguagem: Inglês
10.1021/ol052920y
ISSN1523-7060
AutoresMihyong Kim, John V. Mulcahy, Christine G. Espino, J. Du Bois,
Tópico(s)Synthetic Organic Chemistry Methods
ResumoOxidative C−H amination of N-trichloroethoxysulfonyl-protected ureas and guanidines is demonstrated to proceed in high yield for tertiary and benzylic-derived substrates. The success of these reactions is predicated on the choice of the electron-withdrawn 2,2,2-trichloroethoxysulfonyl (Tces) protecting group, the commercial catalyst Rh2(esp)2 (1−2 mol %), and toluene as solvent. The frequency with which the heterocyclic imidazolidin-2-ones and 2-aminoimidazolines appear as structural elements in both natural products and therapeutically designed molecules confers these methods with a large number of potential applications.
Referência(s)