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Synthesis of diverse ?-quaternary ketones via palladium-catalyzed asymmetric conjugate addition of arylboronic acids to cyclic enones.

ABSTRACT: The development and optimization of a palladium-catalyzed asymmetric conjugate addition of arylboronic acids to cyclic enone conjugate acceptors is described. These reactions employ air-stable and readily-available reagents in an operationally simple and robust transformation that yields ?-quaternary ketones in high yields and enantioselectivities. Notably, the reaction itself is highly tolerant of atmospheric oxygen and moisture and therefore does not require the use of dry or deoxygenated solvents, specially purified reagents, or an inert atmosphere. The ring size and ?-substituent of the enone are highly variable, and a wide variety of ?-quaternary ketones can be synthesized. More recently, the use of NH4PF6 has further expanded the substrate scope to include heteroatom-containing arylboronic acids and ?-acyl enone substrates.

SUBMITTER: Holder JC

PROVIDER: S-EPMC4598955 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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Synthesis of diverse β-quaternary ketones via palladium-catalyzed asymmetric conjugate addition of arylboronic acids to cyclic enones.

Holder Jeffrey C JC Goodman Emmett D ED Kikushima Kotaro K Gatti Michele M Marziale Alexander N AN Stoltz Brian M BM

Tetrahedron 20141128 35

The development and optimization of a palladium-catalyzed asymmetric conjugate addition of arylboronic acids to cyclic enone conjugate acceptors is described. These reactions employ air-stable and readily-available reagents in an operationally simple and robust transformation that yields β-quaternary ketones in high yields and enantioselectivities. Notably, the reaction itself is highly tolerant of atmospheric oxygen and moisture and therefore does not require the use of dry or deoxygenated solv ...[more]

PMID: 26461082

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