Dipyrromethanes are crucial intermediates for the synthesis of substituted porphyrins, expanded porphyrins, porphyrin analogues (dipyrrins, calixpyrroles, chlorins, corroles) and polypyrrolic polymers that are useful in chemistry, physics, biology, medicine and engineering. Dipyrromethanes were also widely used as ligands in organometallic synthesis and catalysis [1-3]. Therefore, the growing interest on these molecules led synthetic chemists to find new routs in order to improve reaction conditions [4,5]. But it is important to pay attention that until now, none of the dipyrromethane synthesis produces the desired compound with all of these parameters: high yields, use of a green solvent or being solvent-free, without any excess of pyrrole and avoiding inconvenient purification. In this report we use an environmentally friendly homogeneous acidic catalyst for a condensation reaction of pyrrole with ketones in the absence of any organic solvent, which provides an efficient route to the synthesis of different substituted dipyrromethanes in an aqueous and green conditions. The FT-IR, 1H-NMR and elemental analysis confirm the structure of compounds.

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