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Oxidative Asymmetric Formal Aza-Diels?Alder Reactions of Tetrahydro-?-carboline with Enones in the Synthesis of Indoloquinolizidine-2-ones.

ABSTRACT: Ru-catalyzed tandem amine oxidative dehydrogenation/formal aza-Diels?Alder reaction for enantio- and diastereoselective synthesis of indoloquinolizidine-2-ones from tetrahydro-?-carbolines and ?,?-unsaturated ketones is described. The reaction proceeds via tandem ruthenium-catalyzed amine dehydrogenation using tert-butyl hydroperoxide (TBHP) as the oxidant and a chiral thiourea-catalyzed formal aza-[4 + 2] cycloaddition, providing a step-economical strategy for the synthesis of these valuable heterocyclic products.

SUBMITTER: Wu X

PROVIDER: S-EPMC6225203 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Oxidative Asymmetric Formal Aza-Diels⁻Alder Reactions of Tetrahydro-β-carboline with Enones in the Synthesis of Indoloquinolizidine-2-ones.

Wu Xiang X Zhao Shi-Bao SB Zheng Lang-Lang LL Li You-Gui YG

Molecules (Basel, Switzerland) 20180901 9

Ru-catalyzed tandem amine oxidative dehydrogenation/formal aza-Diels⁻Alder reaction for enantio- and diastereoselective synthesis of indoloquinolizidine-2-ones from tetrahydro-β-carbolines and α,β-unsaturated ketones is described. The reaction proceeds via tandem ruthenium-catalyzed amine dehydrogenation using tert-butyl hydroperoxide (TBHP) as the oxidant and a chiral thiourea-catalyzed formal aza-[4 + 2] cycloaddition, providing a step-economical strategy for the synthesis of these valuable he ...[more]

PMID: 30200483

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