Abstract Recently, the use of the hypervalent iodine reagent 1‐hydroxy‐1,2‐benziodoxol‐3(1 H )‐one 1‐oxide (IBX) for the oxidation of primary alcohols and aldehydes to carboxylic acids was described. During the synthesis of these carboxylic acids the corresponding N ‐hydroxysuccinimide esters were formed as intermediate products, but their isolation as main reaction products was not successful. We report herein a simple and very efficient method to prepare these synthetically valuable active esters.