TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: Alternatively, producing 5-hydroxymethylfurfural comprises: (i) subjecting a composition comprising fructose to a process in a reactor comprising a reaction medium, where the reaction medium comprises an aqueous phase and an organic phase and where the aqueous phase comprises a salt, and where the reaction medium does not comprise an acidic catalyst or does not comprise a strong acid. The method further comprises: (ii) removing 5-hydroxymethylfurfural from the reactor in step (i). The composition comprising fructose also comprises glucose or mannose. The method prior to step (i) further comprises: (-i) subjecting a composition comprising glucose to an enzymatic reaction catalyzed by glucose isomerase, or subjecting a composition comprising mannose to an enzymatic reaction catalyzed by mannose isomerase. The method further comprises: (iii) removing glucose or mannose from the reactor in step (i), and (iv) converting the glucose or mannose obtained in step (iii) to (a) 5-hydroxymethylfurfural, (b) fructose by an enzymatic reaction catalyzed by glucose isomerase or mannose isomerase. In a second alternative case, producing 5-hydroxymethylfurfural comprises: (x) subjecting a composition comprising glucose to an enzymatic reaction catalyzed by glucose isomerase, or subjecting a composition comprising mannose to an enzymatic reaction catalyzed by mannose isomerase; and (y) subjecting a composition comprising fructose to a process in a reactor comprising a reaction medium, where the reaction medium comprises an aqueous phase and an organic phase and where the aqueous phase comprises a salt. The method comprises: (I) subjecting a composition comprising glucose to an enzymatic reaction catalyzed by glucose isomerase, or subjecting a composition comprising mannose to an enzymatic reaction catalyzed by mannose isomerase; (II) subjecting the composition obtained in step (I) to a process in a reactor comprising a reaction medium, where the reaction medium comprises an aqueous phase and an organic phase and where the aqueous phase comprises a salt. The method comprises: (A) subjecting a composition comprising fructose and glucose, or fructose and mannose, to a process in a reactor comprising a reaction medium, where the reaction medium comprises an aqueous phase and an organic phase and where the aqueous phase comprises a salt; (B) removing the glucose or mannose from the reactor in step (A); and (C) converting the glucose or mannose obtained in step (B) to (a) 5-hydroxymethylfurfural, or (b) fructose by an enzymatic reaction catalyzed by glucose isomerase or mannose isomerase. The aqueous phase of the reaction medium in step (II) and (A) has a pH in the range of 1.0-10. One or more of the steps are performed continuously. The concentration of salt in the aqueous phase of the reaction medium is in the range of 1-20 w/w%. The partition coefficient of the aqueous phase and the organic phase of the reaction medium with respect to 5-hydroxymethylfurfural is at least 1.0. EXAMPLE - No suitable example given.