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Additive-Free Pd-Catalyzed ?-Allylation of Imine-Containing Heterocycles.

ABSTRACT: An additive-free Pd-catalyzed ?-allylation of different imino-group-ontaining heterocycles is reported. The activation of ?-CH pronucleophiles (pK_a (DMSO) > 25) occurs without the addition of strong bases or Lewis acids using only the Pd/Xantphos catalyst system. The reaction scope has been studied for various 5- and 6-membered nitrogen-containing heterocycles (yields up to 96%). Mechanistic investigations suggest an initial allylation of the imine-N followed by a Pd-catalyzed formal aza-Claisen rearrangement.

SUBMITTER: Kljajic M

PROVIDER: S-EPMC5223276 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Additive-Free Pd-Catalyzed α-Allylation of Imine-Containing Heterocycles.

Kljajic Marko M Puschnig Johannes G JG Weber Hansjörg H Breinbauer Rolf R

Organic letters 20161212 1

An additive-free Pd-catalyzed α-allylation of different imino-group-ontaining heterocycles is reported. The activation of α-CH pronucleophiles (pK<sub>a</sub> (DMSO) > 25) occurs without the addition of strong bases or Lewis acids using only the Pd/Xantphos catalyst system. The reaction scope has been studied for various 5- and 6-membered nitrogen-containing heterocycles (yields up to 96%). Mechanistic investigations suggest an initial allylation of the imine-N followed by a Pd-catalyzed formal ...[more]

PMID: 27936786

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