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Switchable Oxidative Reactions of N-allyl-2-Aminophenols: Palladium-Catalyzed Alkoxyacyloxylation vs an Intramolecular Diels-Alder Reaction.

ABSTRACT: The Pd(II)-catalyzed reaction of N-allyl-2-aminophenols in the presence of PhI(OCOR)₂ as the oxidant resulted in an alkoxyacyloxylation process, with the formation of functionalized dihydro-1,4-benzoxazines. The reaction performed in the absence of palladium catalyst switched to an intramolecular Diels-Alder reaction (IMDA) pathway, which was the result of an oxidative dearomatization of the 2-aminophenol, nucleophilic addition, and Diels-Alder reaction cascade, highlighting the role of the oxidant as both a nucleophilic donor and an oxidizing agent.

SUBMITTER: Giofre S

PROVIDER: S-EPMC8524420 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Switchable Oxidative Reactions of N-allyl-2-Aminophenols: Palladium-Catalyzed Alkoxyacyloxylation vs an Intramolecular Diels-Alder Reaction.

Giofrè Sabrina S Keller Manfred M Lo Presti Leonardo L Beccalli Egle M EM Molteni Letizia L

Organic letters 20210927 20

The Pd(II)-catalyzed reaction of N-allyl-2-aminophenols in the presence of PhI(OCOR)2 as the oxidant resulted in an alkoxyacyloxylation process, with the formation of functionalized dihydro-1,4-benzoxazines. The reaction performed in the absence of palladium catalyst switched to an intramolecular Diels-Alder reaction (IMDA) pathway, which was the result of an oxidative dearomatization of the 2-aminophenol, nucleophilic addition, and Diels-Alder reaction cascade, highlighting th ...[more]

PMID: 34570517

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