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Updated: Aug 29, 2025
Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Quaternary and Tertiary Carbon Centers Synthesized via Gallium-Catalyzed Direct Substitution of Unfunctionalized
Clayton P Donald1, Amy Boylan1, Truong N Nguyen1,2
1Department of Chemistry, University of Houston, 3585 Cullen Blvd, Fleming Bldg 112, Houston, Texas 77204-5003, United States.
Abstract:
(IPr)GaCl3/AgSbF6, AgSbF6, and GaCl3 catalyzed substitution of the hydroxyl of secondary and tertiary propargylic alcohols with organoboronic acids via C-C bond formation, and GaCl3 effectively synthesized all-carbon quaternary propargylic centers. These catalysts performed the substitution at carbons bearing alkyl substituents, which has been problematic for other systems. Highly hindered carbon stereocenters were thus produced, including quaternary centers bearing doubly ortho-substituted aryl rings, that are difficult to access with traditional methods.
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