ISSN:
1434-4475
Keywords:
Keywords. Alcohol oxidation; Cp*Rh(ppy) complex; Kinetics.
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Summary. Rh(III) polypyridine complexes ([Cp *Rh(ppy)(H2O)]2+; ppy = 2,2′-bipyridine, 2,2′-bipyridine-4,4′-dicarboxylate, o-phenanthroline, tetrahydro-4,4′-dialkyl-bis-oxazole) oxidize in organic or aqueous alkaline solution primary and secondary alcohols to aldehydes or ketones and are thereby reduced to the Rh(I) complexes Cp *Rh(ppy). The Rh(III) form can be regenerated byoxidants like pyruvate or oxygen, making the reaction quasi-catalytic. The reaction follows anautocatalytic pathway; hydrogen transfer from the α-CH2 group of an alcoholate complex [Cp *Rh(ppy)(OR)]+ to Cp *Rh(I)(ppy) is suggested to yield the Rh(II) intermediate Cp *Rh(ppy)H as the key and rate determining step. The knowledge of Rh(III)/Rh(I) redox potentials allows to estimate the thermodynamic driving force of the reaction which is not more than about 300 mV.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s007060070011
