Mild method for the synthesis of α-glycosyl chlorides: A convenient protocol for quick one-pot glycosylation

• Published in: Carbohydrate research 2023-12, Vol.534, p.108976-108976, Article 108976
• Main Authors: Khanam, Ariza, Dubey, Shashiprabha, Mandal, Pintu Kumar
• Format: Article
• Language: English
• Subjects: C1-hemiacetals; Carbohydrate; chlorides; glycosides; Glycosyl chlorides; Glycosylation; One-pot; Trichloroisocyanuric acid (TCCA)
• ISSN: 0008-6215; 1873-426X
• DOI: 10.1016/j.carres.2023.108976

A simple and efficient protocol for the preparation of α-glycosyl chlorides within 15–30 min is described which employs a stable, cheap, and commercially available Trichloroisocyanuric acid (TCCA) as non-toxic chlorinating agent along with PPh3. This process involved a wide range of substrate scope and is well-suited with labile hydroxyl protecting groups such as benzyl, acetyl, benzoyl, isopropylidene, benzylidene, and TBDPS (tert-butyldiphenylsilyl) groups. This process is operationally simple, mild conditions and obtained good yields with excellent α selectivity. Moreover, a multi-catalyst one-pot glycosylation can be carried out to transform the glycosyl hemiacetals directly to a various O-glycosides in high overall yields without the need for separation or purification of the α-glycosyl chloride donors. [Display omitted] •Synthesis of α-glycosyl chlorides from hemiacetals.•Commercially available, simple, cheap and safe Trichloroisocyanuric acid reagent.•Reaction proceeded under mild reaction conditions at room temperature.•An efficient one-pot, multi-catalytic chlorination/glycosylation sequence.