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Synthesis of α-Tropolones through Autoxidation of Dioxole-Fused Cycloheptatrienes.

ABSTRACT: Herein, we describe the formation of tropolones through the autoxidation of Büchner reaction-derived cycloheptatrienes. The reaction is exceptionally simple procedurally, as it involves blowing a stream of compressed air over the cycloheptatriene, and the products can be obtained without any need for chromatography. The chemistry works specifically on dioxolane-fused systems or close variants, and substitution patterns are also important. A radical-based mechanistic hypothesis is put forward to explain these results. Finally, we demonstrate the utility of the overall process in the synthesis of amide-appended tropolones and an isomer of stipitatic acid.

SUBMITTER: Berkowitz AJ

PROVIDER: S-EPMC9002940 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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Synthesis of α-Tropolones through Autoxidation of Dioxole-Fused Cycloheptatrienes.

Berkowitz Alex J AJ Murelli Ryan P RP

The Journal of organic chemistry 20220110 7

Herein, we describe the formation of tropolones through the autoxidation of Büchner reaction-derived cycloheptatrienes. The reaction is exceptionally simple procedurally, as it involves blowing a stream of compressed air over the cycloheptatriene, and the products can be obtained without any need for chromatography. The chemistry works specifically on dioxolane-fused systems or close variants, and substitution patterns are also important. A radical-based mechanistic hypothesis is put forward to ...[more]

PMID: 35007070

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