Enantioselective para-Claisen Rearrangement for the Synthesis of Illicium-Derived Prenylated Phenylpropanoids

Propargyl Claisen rearrangement: allene synthesis and beyond.

The propargyl Claisen rearrangement is a known protocol to gain access to functionalized allenes through the [3,3]-sigmatropic transformation of propargyl vinyl ethers. The correct use of appropriate propargyl vinyl ethers as starting materials coupled with suitable reaction conditions can aid in the development of new domino methodologies in which the allenes are valuable intermediates in rout...

Synthesis of icariin from kaempferol through regioselective methylation and para-Claisen–Cope rearrangement

The hemisynthesis of the naturally occurring bioactive flavonoid glycoside icariin (1) has been accomplished in eleven steps with 7% overall yield from kaempferol. The 4'-OH methylation of kaempferol, the 8-prenylation of 3-O-methoxymethyl-4'-O-methyl-5-O-prenyl-7-O-benzylkaempferol (8) via para-Claisen-Cope rearrangement catalyzed by Eu(fod)3 in the presence of NaHCO3, and the glycosylation of...

The Claisen Rearrangement

Biomimetic total synthesis of forbesione and desoxymorellin utilizing a tandem Claisen/Diels--Alder/Claisen rearrangement.

A concise synthesis of forbesione (1) and desoxymorellin (3) is presented. Central to the strategy is a biomimetic Claisen/Diels-Alder/Claisen reaction cascade that proceeds in a regioselective manner and produces the desired scaffold exclusively. The observed regioselectivity and product distribution of the Claisen/Diels-Alder/Claisen reaction are attributed to the electronic effects of the xa...

Transannular Claisen rearrangement reactions for the synthesis of vinylcyclobutanes: formal synthesis of (±)-grandisol.

Unsaturated eight-membered lactones undergo decarboxylative and non-decarboxylative transannular Ireland-Claisen rearrangement reactions, to give substituted vinylcyclobutanes. A formal synthesis of (±)-grandisol is described.