Synthesis of macrocyclic propargylic alcohols by ene-type cyclization of unsaturated acetylenic aldehydes
摘要:
Ene type cyclizations of ynals 6,21, and 30 can be effected by EtAlCl2 in CH2Cl2 at -78-degrees-C to afford 14-and 12-membered homoallylic propargylic alcohols in 66-89% yield.
Enantioselective Conversion of Oligoprenol Derivatives to Macrocycles in the Germacrene, Cembrene, and 18-Membered Cyclic Sesterterpene Series
作者:D. Srinivas Reddy、E. J. Corey
DOI:10.1021/jacs.8b10522
日期:2018.12.12
enantio-and diastereoselective process has been developed for the efficient conversion of farnesol and other oligoprenyl alcohols to chiral 10-, 14-, and 18-membered cyclization products, including germacrenol, (+)-costunolide, 3-β-elemol, and epi-mukulol. The key cyclization reaction utilizes ω-bromo aldehyde substrates, a chiral ligand, and indium powder as the reagent at -78 °C and generates 10-, 14-, and
The synthesis of asperidol , an anticancercembrenoid from marine organisms, was achieved starting from allyl alcohol ; the synthetic route was summarized in scheme 1.