METHOD FOR PRODUCING 2-FORMYLFURAN-4-BORONIC ACID

摘要

The invention relates to a method for producing furfural-4-boronic acid by the reaction of furfural acetals (I), which are substituted by halogen in position 4, with boronic acid esters or anhydrides (II), by the subsequent metalation of compound (I) and the simultaneous or subsequent reaction with a boronic acid ester or anhydride (II) to form an acetal-protected furfural-4-boronic acid ester. The product is then subjected to an acid hydrolysis, in which the acetal protection group is eliminated, to form furfural-4-boronic acid (III). In said formulae: X represents chlorine, bromine or iodine; R represents a branched, unbranched and/or cyclic, optionally substituted C₁-C₂₀ and in particular C₁-C₈ alkyl group, an optionally substituted C₆-C₁₂ aryl group or an optionally substituted C₃-C₈ cycloalkyl group, whereby the two groups R together can form a ring; R', R'', R''' independently of one another represent acylic or cyclic, branched or unbranched, optionally substituted C₁-C₂₀ alkyl groups, or optionally substituted aryl groups, whereby optionally two of the groups R', R'' and R''' together form a ring, or represent additional groups B(OR)₃.