Selective Oxidation Reactions of Natural Compounds with Hydrogen Peroxide Mediated by Methyltrioxorhenium

• Main Authors: Giuseppe Trusso Sfrazzetto, Gaetano A. Tomaselli, Rosa M. Toscano, Francesco P. Ballistreri, Andrea Pappalardo, Maria E. Amato
• Format: Article
• Language: English
• Published: MDPI AG 2013-11-01
• Series: Molecules
• Subjects: natural compounds oxidation; hydrogen peroxide; methyltrioxorhenium
• Online Access: http://www.mdpi.com/1420-3049/18/11/13754

We have investigated the oxidative behaviour of natural compounds such as methyl abietate (1), farnesyl acetate (2), α-ionone (3), β-ionone (4), methyl linolelaidate (5), methyl linolenate (6) and bergamottin (7) with the oxidant system methyltrioxo-rhenium/ H2O2/pyridine. The reactions, performed in CH2Cl2/H2O at 25 °C, have shown good regio- and stereoselectivity. The oxidation products were isolated by HPLC or silica gel chromatography and characterized by MS(EI), 1H-, 13C-NMR, APT, gCOSY, HSQC, TOCSY and NOESY measurements. The selectivity seems to be controlled by the nucleophilicity of double bonds and by stereoelectronic and steric effects.