Synthesis 2004(11): 1767-1770  
DOI: 10.1055/s-2004-829119
PAPER
© Georg Thieme Verlag Stuttgart · New York

Chemoselective RuO4 Oxidation of Phenyl or p-Methoxyphenyl Groups to Carboxylic Acid Functions in the Presence of a Tetrahydropyran Ring

L. S. M. Miranda, M. L. A. A. Vasconcellos*
Núcleo de Pesquisas de Produtos Naturais, Universidade Federal do Rio de Janeiro, Lab. H0-27, Bloco H, CCS, Ilha do Fundão, Rio de Janeiro, CEP 21941-590, RJ, Brasil
Fax: +55(21)22702683; e-Mail: mlaav@nppn.ufrj.br;
Further Information

Publication History

Received 8 March 2004
Publication Date:
01 July 2004 (online)

Abstract

We describe the first example of a chemoselective oxidation of phenyl and p-methoxyphenyl groups to carboxylic acid functions in the presence of a tetrahydropyran ring, using 0.02 mol% of RuCl3 and a co-oxidant. The use of NaIO4 as co-oxidant in H2O-CH3CN-CCl4 as the solvent system led to diketone 7. The change of the co-oxidant from sodium periodate to periodic acid and removal of water from the solvent system led to carboxylic acid 2 in good yield as the sole product .