Heterogeneously Catalyzed Domino Synthesis of 3-Indolylquinones Involving Direct Oxidative C-C Coupling of Hydroquinones and Indoles.

ABSTRACT: A domino synthesis of 3-indolylquinones was achieved successfully via direct oxidative C-C coupling of hydroquinones with indoles over Ag₂O and Fe₃O₄/povidone-phosphotungstic acid (PVP-PWA) catalysts using H₂O₂ in tetrahydrofuran at room temperature. Ag₂O catalyzed the in situ oxidation of hydroquinone and 3-indolylhydroquinone intermediates, whereas ferrite solid acid, Fe₃O₄/PVP-PWA, with a 1:4:1 ratio of Fe₃O₄, PVP, and PWA, catalyzed the activation of quinones. The efficiency of this catalytic domino approach was established by a broad scope of substrates involving a variety of hydroquinones and quinones to give high yields (81-97%) of 3-indolylquinones. Fe₃O₄

SUBMITTER: Kamble SB 

PROVIDER: S-EPMC6640916 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature