In modern advances, tris(pentafluorophenyl)borane (commonly known as BCF) catalyst has risen to prominence owing to its extensive versatility in the use of myriad of organic reactions. An efficient and highly stereoselective α-C-glycosylation strategy is presented by employing a catalytic amount of B(C6F5)3 under mild reaction conditions en route to 2,3-unsaturated C-glycosides. The reaction features a broad functional group tolerance including a variety of glycals coupled with allyltrimethylsilane and trimethylsilylphenylacetylene to access the corresponding 2,3-unsaturated allyl- and alkynyl-C-glycosides with excellent α-selectivity. The reaction proceeds in good to excellent yields via concomitant borane activation of glycal donor under mild conditions.
Key words
carbohydrate - glycal - tris(penta - fluorophenyl)borane - stereoselective - C-glycosylation - 2,3-unsaturated C-glycosides
