Synthesis of C-8 alkyl xanthines by pentaamminecobalt(III) complex

Renuka Suravajhala

Department of Science, Systems and Models, Roskilde University, Roskilde, Denmark.

DOI: 10.4236/abc.2013.36058                

Abstract

Alkyl xanthines underwent selective homolytic aromatic substitution at C-8 position with alkyl groups of pentaamminecobalt(III) complex. In this process of synthesis, we used monoalkyl hydrazines as the radical source in aqueous ammonia solution. Evidence supporting coordination of the alkyl hydrazine to pentaamminecobalt(III) complex by radical trapping was in good agreement with literature. The products were characterized using GC-MS and ¹H, ¹⁴N and ⁵⁹Co NMR spectroscopy.

 

Keywords

Alkyl Hydrazine; Radical Alkylation; Caffeine; Homolytic Aromatic Substitution; Pentaamminecobalt(III)

Conflicts of Interest

The authors declare no conflicts of interest.

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