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Metal-free formal synthesis of phenoxazine.

ABSTRACT: A transition metal-free formal synthesis of phenoxazine is presented. The key step of the sequence is a high-yielding O-arylation of a phenol with an unsymmetrical diaryliodonium salt to provide an ortho-disubstituted diaryl ether. This species was cyclized to acetylphenoxazine in moderate yield. The overall yield in the three-step sequence is 72% based on recovered diaryl ether. An interesting, unusually stable iodine(III) intermediate in the O-arylation was observed by NMR and could be converted to the product upon longer reaction time.

SUBMITTER: Kervefors G

PROVIDER: S-EPMC6036965 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Metal-free formal synthesis of phenoxazine.

Kervefors Gabriella G Becker Antonia A Dey Chandan C Olofsson Berit B

Beilstein journal of organic chemistry 20180620

A transition metal-free formal synthesis of phenoxazine is presented. The key step of the sequence is a high-yielding O-arylation of a phenol with an unsymmetrical diaryliodonium salt to provide an ortho-disubstituted diaryl ether. This species was cyclized to acetylphenoxazine in moderate yield. The overall yield in the three-step sequence is 72% based on recovered diaryl ether. An interesting, unusually stable iodine(III) intermediate in the O-arylation was observed by NMR ...[more]

PMID: 30013676

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