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Synthesis of Polycyclic Fused Indoline Scaffolds through a Substrate-Guided Reactivity Switch.

ABSTRACT: Zn(II)-catalyzed divergent synthesis of functionalized polycyclic indolines through formal [3 + 2] and [4 + 2] cycloadditions of indoles with 1,2-diaza-1,3-dienes (DDs) is reported. The nature and type of substituents of substrates are found to act as a chemical switch to trigger two distinct reaction pathways and to obtain two different types of products upon the influence of the same catalyst. The mechanism of both [4 + 2] and [3 + 2] cycloadditions was investigated and fully rationalized by density functional theory (DFT) calculations.

SUBMITTER: Ciccolini C

PROVIDER: S-EPMC8010796 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Synthesis of Polycyclic Fused Indoline Scaffolds through a Substrate-Guided Reactivity Switch.

Ciccolini Cecilia C Mari Giacomo G Gatti Francesco G FG Gatti Giuseppe G Giorgi Gianluca G Mantellini Fabio F Favi Gianfranco G

The Journal of organic chemistry 20200821 17

Zn(II)-catalyzed divergent synthesis of functionalized polycyclic indolines through formal [3 + 2] and [4 + 2] cycloadditions of indoles with 1,2-diaza-1,3-dienes (DDs) is reported. The nature and type of substituents of substrates are found to act as a chemical switch to trigger two distinct reaction pathways and to obtain two different types of products upon the influence of the same catalyst. The mechanism of both [4 + 2] and [3 + 2] cycloadditions was investigated and fully rationalized by d ...[more]

PMID: 32786612

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