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Transition-metal-free allylation of 2-azaallyls with allyl ethers through polar and radical mechanisms.

ABSTRACT: Allylation of nucleophiles with highly reactive electrophiles like allyl halides can be conducted without metal catalysts. Less reactive electrophiles, such as allyl esters and carbonates, usually require a transition metal catalyst to facilitate the allylation. Herein, we report a unique transition-metal-free allylation strategy with allyl ether electrophiles. Reaction of a host of allyl ethers with 2-azaallyl anions delivers valuable homoallylic amine derivatives (up to 92%), which are significant in the pharmaceutical industry. Interestingly, no deprotonative isomerization or cyclization of the products were observed. The potential synthetic utility and ease of operation is demonstrated by a gram scale telescoped preparation of a homoallylic amine. In addition, mechanistic studies provide insight into these C(sp³)-C(sp³) bond-forming reactions.

SUBMITTER: Deng G

PROVIDER: S-EPMC8222226 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Transition-metal-free allylation of 2-azaallyls with allyl ethers through polar and radical mechanisms.

Deng Guogang G Duan Shengzu S Wang Jing J Chen Zhuo Z Liu Tongqi T Chen Wen W Zhang Hongbin H Yang Xiaodong X Walsh Patrick J PJ

Nature communications 20210623 1

Allylation of nucleophiles with highly reactive electrophiles like allyl halides can be conducted without metal catalysts. Less reactive electrophiles, such as allyl esters and carbonates, usually require a transition metal catalyst to facilitate the allylation. Herein, we report a unique transition-metal-free allylation strategy with allyl ether electrophiles. Reaction of a host of allyl ethers with 2-azaallyl anions delivers valuable homoallylic amine derivatives (up to 92%), which are signifi ...[more]

PMID: 34162867

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