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Updated: Dec 10, 2025

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Contiguous Quaternary Carbons: A Selection of Total Syntheses
Alina Eggert1, Christoph Etling1, Dennis Lübken1,2
1Institut für Organische Chemie, Gottfried Wilhelm Leibniz University Hannover und Biomolekulares Wirkstoffzentrum (BMWZ), Schneiderberg 1B, D-30167 Hannover, Germany.
Abstract:
Contiguous quaternary carbons in terpene natural products remain a major challenge in total synthesis. Synthetic strategies to overcome this challenge will be a pivotal prerequisite to the medicinal application of natural products and their analogs or derivatives. In this review, we cover syntheses of natural products that exhibit a dense assembly of quaternary carbons and whose syntheses were uncompleted until recently. While discussing their syntheses, we not only cover the most recent total syntheses but also provide an update on the status quo of modern syntheses of complex natural products. Herein, we review (±)-canataxpropellane, (+)-waihoensene, (-)-illisimonin A and (±)-11-O-debenzoyltashironin as prominent examples of natural products bearing contiguous quaternary carbons.
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