Based on our recent finding that 2,6-dimethoxyphenyl-substitutedNHCs show superior reactivity in the hydroacylation reactions of electron-neutral olefins compared with known NHCs, we now report the syntheses and crystal structures of four highlyelectron-rich2,6-dimethoxyphenyl-substitutedNHCs and show the increase in efficiency caused by the electron-rich aryl substituent in hydroacylation reactions