Nickel-Mediated Synthesis of Non-AnomericC-Acyl Glycosidesthrough Electron Donor-Acceptor Complex Photoactivation

The preparation of nonanomericC-acyl-saccharides has been developed from two different carboxylic acid feedstocks.This transformation is driven by the synergistic interaction of an electron donor-acceptor complex and Ni catalysis. Primary-,secondary-, and tertiary redox-active esters are incorporated as coupling partners onto preactivated pyranosyl- and furanosyl acids,preserving their stereochemical integrity. The reaction occurs under mild conditions, without stoichiometric metal reductants orexogenous catalysts, using commercially available Hantzsch ester as the organic photoreductant.