ABSTRACT We present a new organocatalytic method for synthesizing aldehydes under mild conditions using readily accessible terminal epoxides as starting materials and bis(trifluoromethane)sulfonimide (Tf2NH) as the catalyst. We identified intermediate aldehyde dimerization products at lower temperatures and observed their cleavage at 55°C. We isolated the products in yields of 89–97% using catalyst loadings as low as 0.5 mol%. To underline the applicability of our new approach, we synthesized ibuprofen in a three‐step process and overall yield of 90%.