Tetradecylferrocene:  Ordered Molecular Array of an Organometallic Amphiphile in the Crystal and in a Two-dimensional Assembled Structure on a Surface

Tetradecylferrocene (4, Fc-(CH₂)₁₃CH₃) was synthesized via lithiation of ferrocene by treatment with tert-butyl lithium, followed by alkylation with 1-bromotetradecane. Complex 4 forms a physisorbed ordered molecular monolayer on the surface of highly oriented pyrolytic graphite (HOPG) that was analyzed by scanning tunneling microscopy (STM). It features a lamellar structure with single rows of ferrocenyl moieties separating connecting areas formed by the long alkyl chains which are arranged parallel to each other. The ordering principle of 4 on the surface can be related to the arrangement of Fc-(CH₂)₁₃CH₃ molecules in the three-dimensional crystal lattice.