Nano gamma-Fe2O3-pyridine based catalyst as a new magnetically recyclable heterogeneous organic base was synthesized. The synthesized odorless pyridine based catalyst was used as a new catalyst for the efficient synthesis of beta-phosphonomaionates by the reaction of diethyl phosphite with alpha,beta-unsaturated malonates. The catalyst was easily isolated from the reaction mixture by a magnetic bar and reused at least 10 times without significant degradation in the activity. (C) 2013 Elsevier B.V. All rights reserved.