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Sulfamyl Radicals Direct Photoredox-Mediated Giese Reactions at Unactivated C(3)-H Bonds.

ABSTRACT: Alcohol-anchored sulfamate esters guide the alkylation of tertiary and secondary aliphatic C(3)-H bonds. The transformation proceeds directly from N-H bonds with a catalytic oxidant, a contrast to prior methods which have required preoxidation of the reactive nitrogen center, or employed stoichiometric amounts of strong oxidants to obtain the sulfamyl radical. These sulfamyl radicals template otherwise rare 1,6-hydrogen-atom transfer (HAT) processes via seven-membered ring transition states to enable C(3)-H functionalization during Giese reactions.

SUBMITTER: Kanegusuku ALG

PROVIDER: S-EPMC7359209 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Sulfamyl Radicals Direct Photoredox-Mediated Giese Reactions at Unactivated C(3)-H Bonds.

Kanegusuku Anastasia L G ALG Castanheiro Thomas T Ayer Suraj K SK Roizen Jennifer L JL

Organic letters 20190717 15

Alcohol-anchored sulfamate esters guide the alkylation of tertiary <i>and</i> secondary aliphatic C(3)-H bonds. The transformation proceeds directly from N-H bonds with a catalytic oxidant, a contrast to prior methods which have required preoxidation of the reactive nitrogen center, or employed stoichiometric amounts of strong oxidants to obtain the sulfamyl radical. These sulfamyl radicals template otherwise rare 1,6-hydrogen-atom transfer (HAT) processes via seven-membered ring transition stat ...[more]

PMID: 31313933

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