Oxidative Ring Expansion of Cyclobutanols: Access to Functionalized 1,2-Dioxanes

نویسندگان

چکیده

Cyclobutanols undergo an oxidative ring expansion with Co(acac)2 and triplet oxygen to give 1,2-dioxanols. The formation of alkoxy radical drives the regioselective cleavage on more substituted side before insertion molecular oxygen. reaction is particularly effective secondary cyclobutanols but works also certain tertiary alcohols. Further substitution neutral nucleophiles under catalytic Lewis acid conditions led original 1,2-dioxanes a preferred 3,6-cis-configuration.

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ژورنال

عنوان ژورنال: Organic Letters

سال: 2021

ISSN: ['1523-7060', '1523-7052']

DOI: https://doi.org/10.1021/acs.orglett.1c00070