WebJan 1, 2024 · Inspired by the success of organo-catalyzed glycosylation methodologies and advancements in the development of organic reagent towards glycosylation reactions, in this present communication we report a citric acid mediated synthesis of deoxy O- glycosides via Ferrier rearrangement under mild and environmentally friendly conditions. WebGlycosylation [ 1] = 0.050 M. b Isolated yield. c All selectivities based on 1 H NMR analysis of purified material (see SI ). TTBP = 2,4,6-tri- tert -butylpyrimidine. Further improvements were gained by varying the counterion, additives, and reaction conditions ( Table 2 ).
Combined Lewis acid and Brønsted acid-mediated reactivity of
WebThe stereochemical outcome of glycosylation reactions of 2-deoxy-sugar trichloroacetimidates promoted by chiral Brønsted acids is shown to be dependent on both the chirality of the catalyst and the configuration of the leaving group. High levels of selectivity (1:16 α:β) can be obtained with (S)-catalysts and an α-trichloroacetimidate donor. WebFeb 10, 2024 · A new type of chiral super Brønsted C–H acids, BINOL-derived phosphoryl bis((trifluoromethyl)sulfonyl) methanes (BPTMs), were developed. As compared to widely utilized BINOL-derived chiral phosphoric acids (BPAs) and N-triflyl phosphoramides (NTPAs), BPTMs displayed much higher Brønsted acidity, resulting in dramatically … birchmont turnament
Chiral Brønsted Acid from Chiral Phosphoric Acid Boron Complex …
WebOct 11, 2024 · Chiral Brønsted acid catalysis is mostly limited to the activation of imine and carbonyl moieties. ... Qian, P.-C. & Ye, L.-W. Brønsted acid-mediated reactions of … WebJul 21, 2024 · Abstract Chiral Brønsted acids have found widespread applications as organocatalysts. Weakly acidic species such as diols and (thio)ureas, typically classified as hydrogen bonding catalysts, as well as … WebT Kimura, M Sekine, D Takahashi, K Toshima, Chiral Brønsted acid mediated glycosylation with recognition of alcohol chirality. Angew Chem Int Ed Engl 52, … birch moon