Abstract A series of polyiminopyridines ( PIPys ) were reported and used as supports to prepare heterogenized‐iron catalysts ( FePIPys ). The resulting PIPys exhibit moderate surface areas (S BET ≈ 200 m 2 g −1 ) and high chemical and thermal stability. The catalytic performance of FePIPys–catalyts was studied in the acetalization of furfural and 5‐hydroxymethyl furfural to yield compounds of potential interest as diesel additives. The structure of the polyiminopyridine support has great influence in the catalytic performance and recyclability; all catalysts maintained the activity and the selectivity after several cycles.