Boronic Acid/Palladium Hybrid Catalysis for Regioselective O-Allylation of Carbohydrates

Abstract

Novel imidazole-containing boronic acid and palladium hybrid catalysis for regioselective O-allylation of carbohydrates has been developed. This catalytic process enables the introduction of a useful allyl functional group into the equatorial hydroxy group of cis-1,2-diols of various carbohydrates with low catalyst loading and excellent regioselectivities. This is the first report on hybrid catalysis in combination with a Lewis base-containing boronic acid and a transition metal complex.

Synergistic Organoboron/Palladium Cocatalyzed Dehydrative Couplings of Azoles with Allylic Alcohols: A Combined Experimental and Computational Mechanistic Investigation

“…By employing allylic alcohols as the electrophiles in the presence of a palladium bis­(phosphine) cocatalyst, regioselective dehydrative N-allylations of various azoles were achieved (Scheme ). − Control experiments showed that the organoboron catalyst has a significant effect on both reaction rate and N-allylation regioselectivity, suggesting that it plays a role both in activating the allylic alcohol electrophile, in cooperation with the Xantphos­(Pd) complex, and the azole nucleophile. , The allylation method has been extended to other NH-pronucleophiles, including pyridones and sulfoximines …”