Asymmetric total synthesis of (+)-cardiobutanolide via an iterative asymmetric dihydroxylation in PEG
作者:S. Chandrasekhar、N. Kiranmai
DOI:10.1016/j.tetlet.2010.05.122
日期:2010.8
The stereoselective total synthesis of (+)-cardiobutanolide, a polyhydroxylated natural product, is achieved in high yield through Lu and Guo diene synthesis, Sharpless asymmetricdihydroxylation, and one-pot deprotection–lactonization. The utility of a recyclable reagent system in PEG for asymmetricdihydroxylation is demonstrated.
The asymmetric synthesis of the fully functionalized macrocyclic core of iriomoteolide 3a, a cytotoxic 15-membered macrolide, Is disclosed. The key steps involve Sharpless asymmetric dihydroxylation, Sharpless asymmetric epoxidation, olefin cross-metathesis, Yamaguchi esterification, and a ring-closing metathesis reaction for macrocyclization.
Copper-Catalyzed Methylenation Reaction: Total Synthesis of (+)-Desoxygaliellalactone
作者:Hélène Lebel、Michaël Parmentier
DOI:10.1021/ol071391q
日期:2007.8.1
The enantioselective total synthesis of (+)-desoxygaliellalactone was achieved in six steps starting from 4-tert-butyldimethylsilyloxybutanal. This synthesis featured a one-pot copper-catalyzed methylenation-Diels-Alder cyclization. The challenging methylenation of aldehyde 4 was studied under various reaction conditions. Whereas Wittig reaction conditions led to byproducts resulting from decomposition of the sensitive butenolide moiety, the mild copper-catalyzed methylenation reaction produced the desired triene in good yield.