Asymmetric Synthesis of All-Carbon Quaternary Spirocycles via a Catalytic Enantioselective Allylic Alkylation Strategy

Samantha E Shockley; J Caleb Hethcox; Brian M Stoltz

doi:10.1016/j.tetlet.2017.07.022

Asymmetric Synthesis of All-Carbon Quaternary Spirocycles via a Catalytic Enantioselective Allylic Alkylation Strategy

Tetrahedron Lett. 2017 Aug 23;58(34):3341-3343. doi: 10.1016/j.tetlet.2017.07.022. Epub 2017 Jul 5.

Authors

Samantha E Shockley¹, J Caleb Hethcox¹, Brian M Stoltz¹

Affiliation

¹ The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Blvd, MC 101-20, Pasadena, California 91125, United States.

Abstract

Rapid access to enantioenriched spirocycles possessing a 1,4-dicarbonyl moiety spanning an all-carbon quaternary stereogenic spirocenter was achieved using a masked bromomethyl vinyl ketone reagent. The developed protocol entails an enantioselective palladium-catalyzed allylic alkylation reaction followed by a one-pot unmasking/RCM sequence that provides access to the spirocyclic compounds in good yields and selectivities.

Keywords: Allylic alkylation; Asymmetric catalysis; Masked bromomethyl vinyl ketone; Palladium catalysis; Spirocycle.

Abstract

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