Cross‐Coupling Reaction of Saccharide‐Based Alkenyl Boronic Acids with Aryl Halides: The Synthesis of Bergenin

Abstract

A convenient synthetic pathway enabling D-glucal and D-galactal pinacol boronates to be prepared in good isolated yields was achieved. Both pinacol boronates were tested in a series of cross-coupling reactions under Suzuki-Miyaura cross-coupling conditions to obtain the corresponding aryl, heteroaryl, and alkenyl derivatives in high isolated yields. This methodology was applied to the formal synthesis of the glucopyranoside moiety of papulacandin D and the first total synthesis of bergenin.

Glycoconjugated Phthalocyanines as Photosensitizers for PDT – Overcoming Aggregation in Solution

“…The starting material was reisolated under various conditions tested so far (hydrogenation with Pd/C in hexane, ethyl acetate, toluene, methanol and ethyl acetate, with Pt/C in ethanol and with Pd(OH) 2 in ethanol , BH 3 · SMe 2 ,, and 9‐BBN were also tested for hydroboration of the double bonds but did not react with 34 either. Obviously, the orientation of the silylgroups of the sugar moiety in 34 prevents hydrogenation.…”

Diversity, pharmacology and synthesis of bergenin and its derivatives: Potential materials for therapeutic usages

“…18) [238]. Hydroboration-oxidation of the SuzukiMiyaura cross-coupling product 129 furnished arylglucoside 130 diastereoselectively.…”

Homogeneous Catalysis: A Powerful Technology for the Modification of Important Biomolecules

“…[48] Palladium-and nickel-catalyzedS uzuki-Miyaura cross-coupling reactions of glycal boronates with aryl and alkyl halides for the synthesis of C-glycosides was also explored. [49] Recently,W u, Ye,a nd co-workers demonstrated ap alladiumcatalyzed ortho-CÀH-activation-based approach for the synthesis of C-aryl glycosides. [50] Differently substituted N-quinolyl benzamides 53 were reacted with 1-iodoglycals 54 under the optimized reaction conditions to furnish ad iverser ange of Caryl glycals 55 in good-to-excellent yields (Scheme 14).…”