Green synthesis of 5-hydroxymethylfurfural and 5-acetoxymethylfurfural using a deep eutectic solvent in a biphasic system assisted by microwaves

The fructose was subjected to a dehydration reaction to produce 5-hydroxymethylfurfural using a deep eutectic solvent composed of choline chloride, fructose, water as the third component of the mixture and p -sulfonic acid calix[4]arene as an organocatalyst.