Showing papers on "Ferrier rearrangement published in 2017"
TL;DR: In this paper, a method to obtain enantiomerically pure 8-oxabicyclo[3.2.1] octanes via gold-catalyzed tandem 1,3-acyloxy migration/Ferrier rearrangement of glycal derived 1,6-enyne bearing propargylic carboxylates is described.
Abstract: Herein, we describe an efficient method to prepare enantiomerically pure 8-oxabicyclo[3.2.1]octanes via gold(I)-catalyzed tandem 1,3-acyloxy migration/Ferrier rearrangement of glycal derived 1,6-enyne bearing propargylic carboxylates. The resultant compounds could then undergo interrupted Nazarov cyclization to afford diastereomerically pure 11-oxatricyclo[5.3.1.0]undecanes.
20 citations
TL;DR: One-pot carbon-Ferrier rearrangement of glycals with unactivated aryl methyl ketones has been developed under mild Silyl triflate catalysis and has been extended to the synthesis of a small library of chromanone 3-C-glycosides.
5 citations
TL;DR: By using Hf(OTf)4 as the catalyst, a series of 2,3-N- and C-unsaturated-glucosides have been synthesized from 3,4,6-tri-O-acetyl-d -glucal, 2, 4,6,tri- O-benzyl- d -GLucal and ((2R,3S)-3-acetoxy-2,3,dihydrofuran-2-yl)methyl acetate under mild reaction conditions in good yields with high
5 citations
TL;DR: In this paper, the preparation of eight 2,3-unsaturated O-glycosides from D-glycals and alcohols, using montmorillonite K-10 as an acid catalyst, is described.
Abstract: Abstract The preparation of eight 2,3-unsaturated O-glycosides from D-glycals and alcohols, using montmorillonite K-10 as an acid catalyst, is described. The Ferrier rearrangement products were obtained in good yields using conventional heating and microwave irradiation but the reaction time was substantially reduced employing the latter procedure. The yields were slightly lower under microwave exposure. Five of the di-O-acetylated products were deacetylated to the glycosides in excellent yields. The acetylated products possess good anti-inflammatory property suggesting that the acetyl group plays an important role in reducing the inflammation. Among the compounds tested, glycosides containing thiophene as an aglycone present much better inflammation reducing characteristics than the analogues without this function.
1 citations
TL;DR: The catalyst-free addition of organozinc species to glycal derivatives and dihydropyrans in a toluene/ n -dibutyl ether solvent mixture via a Ferrier rearrangement at room temperature requires only a slight excess of the nucleophile and leads preferentially to the C-glycoside α-anomer.
Abstract: Herein, we report the catalyst-free addition of organozinc species to glycal derivatives and dihydropyrans in a toluene/ n -dibutyl ether solvent mixture via a Ferrier rearrangement at room temperature. This methodology requires only a slight excess of the nucleophile and leads preferentially to the C-glycoside α-anomer. Various 1,2-dihydropyrans were assessed with a range of nucleophiles (aryl, alkynyl, alkyl) yielding the desired C -glycosides in good yield and diastereoselectivity up to 20:1.
1 citations