Claisen Rearrangement Triggered by Brønsted Acid Catalyzed Alkyne Alkoxylation

Abstract

Over the past two decades, catalytic alkyne alkoxylation-initiated Claisen rearrangement has proven to be a practical and powerful strategy for the rapid assembly of a diverse range of structurally complex molecules. The rapid development of Claisen rearrangements triggered by transition-metal-catalyzed alkyne alkoxylation has shown great potential in the formation of carbon–carbon bonds in an atom-economic and mild way. However, metal-free alkyne alkoxylation-triggered Claisen rearrangement has seldom been exploited. Recently, Brønsted acids such as HNTf2 and HOTf have been shown to be powerful activators that promote catalytic alkyne alkoxylation/Claisen rearrangement, leading to the concise and flexible synthesis of valuable compounds with high efficiency and atom economy. Recent advances on the Brønsted acid catalyzed alkyne alkoxylation/Claisen rearrangement are introduced in this Account, in which both intramolecular and intermolecular tandem reactions are discussed.

Cobalt(II)-Catalyzed Enantioselective Propargyl Claisen Rearrangement: Access to Allenyl-Substituted Quaternary β-Ketoesters

“…Claisen rearrangement has emerged as a powerful C–C bond forming method, which is an indispensable tool due to the utility of the products in the construction of complex organic molecules . Considerable advancements have been made in the catalytic asymmetric Claisen rearrangement of allyl vinyl ethers .…”