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A regioselectivity switch in Pd-catalyzed hydroallylation of alkynes.

ABSTRACT: By exploiting the reactivity of a vinyl-Pd species, we control the regioselectivity in hydroallylation of alkynes under Pd-hydride catalysis. A monophosphine ligand and carboxylic acid combination promotes 1,5-dienes through a pathway involving isomerization of alkynes to allenes. In contrast, a bisphosphine ligand and copper cocatalyst favor 1,4-dienes via a mechanism that involves transmetalation. Our study highlights how to access different isomers by diverting a common organometallic intermediate.

SUBMITTER: Ji DW

PROVIDER: S-EPMC6598511 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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A regioselectivity switch in Pd-catalyzed hydroallylation of alkynes.

Ji Ding-Wei DW Hu Yan-Cheng YC Zheng Hao H Zhao Chao-Yang CY Chen Qing-An QA Dong Vy M VM

Chemical science 20190516 25

By exploiting the reactivity of a vinyl-Pd species, we control the regioselectivity in hydroallylation of alkynes under Pd-hydride catalysis. A monophosphine ligand and carboxylic acid combination promotes 1,5-dienes through a pathway involving isomerization of alkynes to allenes. In contrast, a bisphosphine ligand and copper cocatalyst favor 1,4-dienes <i>via</i> a mechanism that involves transmetalation. Our study highlights how to access different isomers by diverting a common organometallic ...[more]

PMID: 31341584

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