Hydrogen bond catalyzed Mukaiyama aldol reactions of alpha-ketoesters proceed in high diastereo- and enantioselectivities, giving products possessing two chiral centers, of which one is a tertiary alcohol.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1039/b919929b | DOI Listing |
J Am Chem Soc
December 2024
Department of Chemistry, Rice University, Houston, Texas 77005, United States.
Concise total syntheses of several 5/7/6 norcembranoids, including ineleganolide, scabrolide B, sinuscalide C, and fragilolide A have been achieved through a fragment coupling/ring closure approach. The central seven-membered ring was forged through sequential Mukaiyama-Michael/aldol reactions using norcarvone and a decorated bicyclic lactone incorporating a latent electrophile. Subsequent manipulations installed the reactive enedione motif and delivered scabrolide B in 11 steps from a chiral pool-derived enone.
View Article and Find Full Text PDFOrg Lett
November 2024
State Key Laboratory of Environmental Chemistry and Eco-toxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Thuggacin A () is a 17-membered-ring-polyketide antibiotic compound with excellent antituberculosis activity. The total synthesis of thuggacin A has not yet been reported so far. Herein, we disclose our efforts toward the convergent total synthesis of thuggacin A.
View Article and Find Full Text PDFIn the fields of polymer and material chemistries, strong acid units have mainly included sulfonic acids, which has limited the extension of related material chemistries. Here, a unique carbon acid functionality, namely the bis[(trifluoromethyl)sulfonyl]methyl group, was integrated with polymers a simple postpolymerization modification with the outstandingly electrophilic 1,1-bis[(trifluoromethyl)sulfonyl]ethylene. The proposed synthesis protocol was verified as an efficient process even for solid-state reactions.
View Article and Find Full Text PDFOrg Biomol Chem
October 2024
School of Chemical Sciences, The University of Auckland, 23 Symonds Street, Auckland, 1010, New Zealand.
Pallamolide A is a 7,8--labdane terpenoid possessing a unique bicyclo[2.2.2]octane core and a spiro-butenolide moiety.
View Article and Find Full Text PDFJ Org Chem
May 2024
CNRS, CiTCoM, Faculté de Pharmacie, Université Paris Cité, 4, avenue de l'Observatoire, F-75006 Paris, France.
In this paper are presented the results of the preliminary studies conducted on two model substrates that allowed the testing of various strategies and set the proper conditions that thereafter culminated in the synthesis of the C1-C23 chain of enacyloxin-IIa and its congeners. Innovative strategic options were explored on each model allowing the stereochemical control of the following two elements: (a) the 2, 4, 6, 8, and 10 chlorinated undecapentaenoic chain, thanks to -selective Kaneda's alkyne allylchlorination and an -selective Pd/Cu allene-alkyne coupling and (b) the unusual - -OH/-Cl/-OCONH 17-19 triad, thanks to a highly diastereoselective Mukaiyama aldol reaction.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!