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Palladium-catalyzed tandem allylic substitution/cyclization and cascade hydrosilylated reduction: the influence of reaction parameters and hydrosilanes on the stereoselectivity.

ABSTRACT: To shed light on the influence of reaction parameters on palladium-catalyzed tandem allylic alkylation in the presence of Fei-Phos (a chiral trans-1,2-diaminocyclohexane-derived phosphine ligand), the effect of different phosphine ligands, inorganic or organic bases, Brønsted acids, and other additives on the asymmetric palladium-catalysed alkylation of catechol with allylic diacetate was investigated. In this reaction, 2-vinyl-2,3-dihydro-benzo[1,4]dioxin products with promising enantioselectivity were achieved in good yields. In addition, a novel palladium-catalyzed three-component and one-pot allylic substitution/cyclization/reduction reaction assisted by methylphenylsilane was reported with good selectivity.

SUBMITTER: Long PW

PROVIDER: S-EPMC9081657 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Palladium-catalyzed tandem allylic substitution/cyclization and cascade hydrosilylated reduction: the influence of reaction parameters and hydrosilanes on the stereoselectivity.

Long Peng-Wei PW Xu Jian-Xing JX Bai Xing-Feng XF Xu Zheng Z Zheng Zhan-Jiang ZJ Yang Ke-Fang KF Li Li L Xu Li-Wen LW

RSC advances 20180622 41

To shed light on the influence of reaction parameters on palladium-catalyzed tandem allylic alkylation in the presence of Fei-Phos (a chiral <i>trans</i>-1,2-diaminocyclohexane-derived phosphine ligand), the effect of different phosphine ligands, inorganic or organic bases, Brønsted acids, and other additives on the asymmetric palladium-catalysed alkylation of catechol with allylic diacetate was investigated. In this reaction, 2-vinyl-2,3-dihydro-benzo[1,4]dioxin products with promising enantios ...[more]

PMID: 35540169

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