Efficient metal-free conversion of glucose to 5-hydroxymethylfurfural using a boronic acid

5-Hydroxymethylfurfural (HMF), which can be synthesized from hexose sugars without rearrangement of their carbon framework, is a key platform chemical that is readily convertible into fuels and chemicals that are now derived from petroleum. Methods to convert glucose, which is readily accessible from cellulose, to HMF typically rely on toxic heavy metals or harsh acidic conditions and often give low yields or low selectivity. Here, we report on a mild, efficient, and metal-free process that uses an organocatalyst, 2-carboxyphenylboronic acid, along with small amounts of chloride ion to effect the selective transformation of glucose to HMF.