The totalsynthesis of the smallest cytochalasin isolated so far, periconiasin G, which bears a seven‐membered ring in lieu of the usual macrocycle, has been performed from both enantiomers of citronellal, relying on an intramolecular Diels–Alder reaction in favor of the natural endo stereochemistry. We show that, among the four synthesized stereoisomers, including the exo isomers, the one matching
Cyclopentyl methyl ether, a low impact ether forming a positive azeotrope with water, was successfully employed as a solvent in the synthesis of 1,3-dioxanes and 1,3-dioxolanes carried out under Dean-Stark...
Highly Efficient Acetalization of Carbonyl Compounds Catalyzed by Aniline–Aldehyde Resin Salts
作者:Kiyoshi Tanemura、Tsuneo Suzuki
DOI:10.1246/cl.150166
日期:2015.6.5
A mild procedures for the syntheses of ethylene acetals and dimethyl acetals from the corresponding aldehydes and ketones catalyzed by 1 mol % of aniline–aldehyde resin salts are described. This method is also useful for the synthesis of dimethyl acetals of diaryl ketones.
作者:Marc Heinrich、John J. Murphy、Marina K. Ilg、Aurélien Letort、Jakub Flasz、Petra Philipps、Alois Fürstner
DOI:10.1002/anie.201808937
日期:2018.10.8
centered on cobalt‐catalyzed oxidative cyclization reactions of hydroxylated olefin precursors, which allowed the 2,5‐trans‐disubstituted tetrahydrofuran rings, embedded into each building block, to be formed with excellent selectivity. The highly strained macrolactone could ultimately be closed under forcing Yamaguchi conditions. Comparison of the spectral data of the synthetic sample with those of authentic
Staring from d-citronellal of natural origin, d-iridodial and d-isoiridomyrmecin were synthesised. 1 The latter furnished, on oxidation, a nepetalinic acid, which was the enantiomorph of a degradation product of nepetalactone. A mixture of the two specimens afforded a racemate of higher melting point.