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Stereoselective Synthesis of Highly Substituted 1,3-Dienes via "a la carte" Multifunctionalization of Borylated Dendralenes.

ABSTRACT: Despite the high relevance of 1,3-dienes, stereoselective methods to access tetrasubstituted conjugated dienes are still scarce. We here report an efficient and modular approach that provides access to multifunctional tetrasubstituted 1,3-dienes with excellent levels of regio- and stereoselectivity. This methodology is based on a tetracomponent reaction between a borylated dendralene, an organolithium reagent and two different electrophiles. Mechanistic studies reveal that this transformation proceeds through a regio- and stereoselective carbolithiation/electrophilic trapping of an in situ formed dendralenic boron-ate complex, followed by a stereoretentive halodeborylation. The ease in which complex structural dienes can be accessed and their synthetic versatility highlight the importance and utility of this method.

SUBMITTER: Rivera-Chao E

PROVIDER: S-EPMC8362018 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Stereoselective Synthesis of Highly Substituted 1,3-Dienes via "à la carte" Multifunctionalization of Borylated Dendralenes.

Rivera-Chao Eva E Fañanás-Mastral Martín M

Angewandte Chemie (International ed. in English) 20210626 31

Despite the high relevance of 1,3-dienes, stereoselective methods to access tetrasubstituted conjugated dienes are still scarce. We here report an efficient and modular approach that provides access to multifunctional tetrasubstituted 1,3-dienes with excellent levels of regio- and stereoselectivity. This methodology is based on a tetracomponent reaction between a borylated dendralene, an organolithium reagent and two different electrophiles. Mechanistic studies reveal that this transformation pr ...[more]

PMID: 34043856

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