Sterically Strained Bronsted Pair Catalysis by Bulky Pyridinium Salts: Direct Stereoselective Synthesis of 2-Deoxy and 2,6-Dideoxy-β-thioglycosides from Glycals was written by Mukherji, Ananya;Addanki, Rupa Bai;Halder, Suvendu;Kancharla, Pavan K.. And the article was included in Journal of Organic Chemistry in 2021.Recommanded Product: (3aR,5S,6S,6aR)-5-((R)-2,2-Dimethyl-1,3-dioxolan-4-yl)-2,2-dimethyltetrahydrofuro[2,3-d][1,3]dioxol-6-ol This article mentions the following:
A sterically strained ionic Bronsted pair complex obtained from a sterically bulky base 2,4,6-tri-tert-butylpyridine and hydrochloric acid unusual reactivity to the anionic chloride. The complete shielding of the cationic [N-H]+ by the bulky ortho-tert-Bu groups weakens the possible hydrogen-bonding interactions with the chloride anion, and the [N-H]+···Cl– distance is unusually longer (3.10 Å). This results in strained/frustrated electrostatic interactions between the ion-pair, thus infusing an increased reactivity in both of the ions, which results in the activation of a third mol. like thiol via hydrogen-bonding. This intriguing weak interaction-based reactivity has been utilized to develop an organocatalytic synthesis of 2-deoxy-β-thioglycosides from glycals. While the 1H NMR studies showcase the diamagnetic activation of thiols in the presence of the catalyst, the ESR (EPR) studies reveal the generation of a radical species that suggests a possible frustrated radical pair catalysis. Besides, IR spectroscopic studies explain the intriguing influence of size/charge d. of the anion on the solvation-insusceptible, cationic [TTBPyH]+ and on the observed reactivity. In the experiment, the researchers used many compounds, for example, (3aR,5S,6S,6aR)-5-((R)-2,2-Dimethyl-1,3-dioxolan-4-yl)-2,2-dimethyltetrahydrofuro[2,3-d][1,3]dioxol-6-ol (cas: 582-52-5Recommanded Product: (3aR,5S,6S,6aR)-5-((R)-2,2-Dimethyl-1,3-dioxolan-4-yl)-2,2-dimethyltetrahydrofuro[2,3-d][1,3]dioxol-6-ol).
(3aR,5S,6S,6aR)-5-((R)-2,2-Dimethyl-1,3-dioxolan-4-yl)-2,2-dimethyltetrahydrofuro[2,3-d][1,3]dioxol-6-ol (cas: 582-52-5) belongs to tetrahydrofuran derivatives. Tetrahydrofuran and dihydrofuran form the basic structural unit of many naturally occurring scaffolds like gambieric acid A and ciguatoxin, goniocin, and some biologically active molecules. Tetrahydrofuran reaction with hydrogen sulfide: In the presence of a solid acid catalyst, tetrahydrofuran reacts with hydrogen sulfide to give tetrahydrothiophene.Recommanded Product: (3aR,5S,6S,6aR)-5-((R)-2,2-Dimethyl-1,3-dioxolan-4-yl)-2,2-dimethyltetrahydrofuro[2,3-d][1,3]dioxol-6-ol
Referemce:
Tetrahydrofuran – Wikipedia,
Tetrahydrofuran | (CH2)3CH2O – PubChem