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Singlet oxygen-mediated selective C-H bond hydroperoxidation of ethereal hydrocarbons.

ABSTRACT: Singlet O2 is a key reactive oxygen species responsible for photodynamic therapy and is generally recognized to be chemically reactive towards C=C double bonds. Herein, we report the hydroperoxidation/lactonization of ?-ethereal C-H bonds by singlet O2 (1?g) under exceptionally mild conditions, i.e., room temperature and ambient pressure, with modest to high yields (38~90%) and excellent site selectivity. Singlet O2 has been known for >?90 years, but was never reported to be able to react with weakly activated C-H bonds in saturated hydrocarbons. Theoretical calculations indicate that singlet O2 directly inserts into the ?-ethereal C-H bond in one step with conservation of steric configuration in products. The current discovery of chemical reaction of singlet oxygen with weakly activated solvent C-H bonds, in addition to physical relaxation pathway, provides an important clue to a 35-year-old unresolved mystery regarding huge variations of solvent dependent lifetime of singlet O2.

SUBMITTER: Sagadevan A

PROVIDER: S-EPMC5703888 | biostudies-other | 2017 Nov

REPOSITORIES: biostudies-other

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Singlet oxygen-mediated selective C-H bond hydroperoxidation of ethereal hydrocarbons.

Sagadevan Arunachalam A Hwang Kuo Chu KC Su Ming-Der MD

Nature communications 20171127 1

Singlet O2 is a key reactive oxygen species responsible for photodynamic therapy and is generally recognized to be chemically reactive towards C=C double bonds. Herein, we report the hydroperoxidation/lactonization of α-ethereal C-H bonds by singlet O2 (1Δg) under exceptionally mild conditions, i.e., room temperature and ambient pressure, with modest to high yields (38~90%) and excellent site selectivity. Singlet O2 has been known for > 90 y ...[more]

PMID: 29180784

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