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Different 1-substituted-(pyrrole alkyl)phosphonic acid derivatives have been designed as adhesion promoters to graft polypyrrole layers on several substrates. These compounds contain two reactive, terminal moieties: the phosphonic acid group as anchor to the oxide surface and the pyrrolyl group, which functions as starting unit for surface polymerisation. Both groups are connected by an alkyl spacer ranging from 4 to 12 methylene units. The short- and long-chain derivatives were synthesized for the first time to study their self-assembling properties and their effectiveness to be used as an adhesion promoter for grafting covalently bound polypyrrole layers on oxide substrates. Surfactant-like properties of the long chain derivatives and their behaviour in water for pyrrole polymerization were also investigated, as will be discussed in future papers. In this first paper of the series, the synthesis and characterization of the monomers are presented. The structure of the molecules was proven by 1H-NMR, 31P-NMR and FT-IR spectroscopy. Thermogravimetry analysis (TGA) and differential scanning calorimetry (DSC) revealed that the stability of the compound depended on their chain length: the longer the alkyl chain, the more stable the monomer. On the other hand, reactivity decreased with increasing chain length, as proven by cyclic voltammetry measurements (CV). [ABSTRACT FROM AUTHOR]