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Selective oxidation reactions of natural compounds with hydrogen peroxide mediated by methyltrioxorhenium.

ABSTRACT: We have investigated the oxidative behaviour of natural compounds such as methyl abietate (1), farnesyl acetate (2), ?-ionone (3), ?-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.

SUBMITTER: Amato ME

PROVIDER: S-EPMC6270049 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature

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Selective oxidation reactions of natural compounds with hydrogen peroxide mediated by methyltrioxorhenium.

Amato Maria E ME Ballistreri Francesco P FP Pappalardo Andrea A Tomaselli Gaetano A GA Toscano Rosa M RM Sfrazzetto Giuseppe Trusso GT

Molecules (Basel, Switzerland) 20131107 11

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, HS ...[more]

PMID: 24213654

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