AbstractAn extremophilic challenge: Stereospecific condensation of a fully functionalized ketal aldehyde and a 2,6‐dihydroxybenzoic acid is the key step in the synthesis of (−)‐berkelic acid confirming Fürstner's reassignment of the stereochemistry at C18 and C19, establishing the absolute stereochemistry, and tentatively assigning the stereochemistry at C22.magnified image
AbstractAn extremophilic challenge: Stereospecific condensation of a fully functionalized ketal aldehyde and a 2,6‐dihydroxybenzoic acid is the key step in the synthesis of (−)‐berkelic acid confirming Fürstner's reassignment of the stereochemistry at C18 and C19, establishing the absolute stereochemistry, and tentatively assigning the stereochemistry at C22.magnified image
Catalytic Asymmetric Synthesis of (+)-Anthecotulide Using Enyne and Meyer–Schuster Rearrangements
作者:David M. Hodgson、Eric P. A. Talbot、Barry P. Clark
DOI:10.1021/ol202425e
日期:2011.11.4
The bioactive sesquiterpene lactone (+)-anthecularin (1) is synthesized for the first time, in a six-step sequence devoid of protecting groups. The key transformations are a novel Rh(I)-catalyzed asymmetric enyne rearrangement of a terminal alkynyl ester (4), to form the alpha-methylene-gamma-butyrolactone core, and a final-step mild Au(I)-catalyzed Meyer-Schuster rearrangement