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Ce(IV) – Induced electron transfer in Pentaammine Cobalt (III) complexes of -amino acids in micellar mediumKeywords: Pentaamminecobalt(III) complexes , Induced electron transfer reaction , Micelles , Triol , Complex formation. Abstract: :A micellar catalysed oxidation of pentaamminecobalt(III) complexes of - amino acids by Ce(IV) in acidic medium yielding nearly 40% of Co(II), 40% of HCHO and about 60% of glyoxalatocobalt(III) complex are ultimate products. The unbound amino acids yield about 40% of HCHO and 60% of glyoxalic acid in presence of micelles. The effect of variation of sulphuric acid concentration is not substantial. The decrease in UV-Visible absorbance at λ = 502 nm for Co(III) complex corresponds to nearly 40% of the initial absorbance. In spite of the stoichiometry of Ce(IV) to unbound ligand is 2.0:1.0, the ratio of Ce(IV) to cobalt(III) complex is 1.5:1.0 accounting for about 40% reduction at the cobalt(III) centre. The kinetic and stoichiometric results have been accounted. A suitable mechanism consistent with the experimental findings has been proposed by involving a radical cation intermediate.Keywords: :A micellar catalysed oxidation of pentaamminecobalt(III) complexes of - amino acids by Ce(IV) in acidic medium yielding nearly 40% of Co(II), 40% of HCHO and about 60% of glyoxalatocobalt(III) complex are ultimate products. The unbound amino acids yield about 40% of HCHO and 60% of glyoxalic acid in presence of micelles. The effect of variation of sulphuric acid concentration is not substantial. The decrease in UV-Visible absorbance at λ = 502 nm for Co(III) complex corresponds to nearly 40% of the initial absorbance. In spite of the stoichiometry of Ce(IV) to unbound ligand is 2.0:1.0, the ratio of Ce(IV) to cobalt(III) complex is 1.5:1.0 accounting for about 40% reduction at the cobalt(III) centre. The kinetic and stoichiometric results have been accounted. A suitable mechanism consistent with the experimental findings has been proposed by involving a radical cation intermediate.
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