We describe a new approach for solution processing of crystalline monolayers of an alkyl-substituted polycyclic aromatic hydrocarbon molecule on the basal plane of graphite. These layers are prepared by first adsorbing a soluble oligophenyl precursor at a solid-liquid interface and subsequently performing the oxidative cyclodehydrogenation reaction to the final fused product in-situ. Scanning tunneling microscopy imaging with submolecular resolution allowed visualization of the ordered nanostructures of both the precursors and the final organic adlayer, proving that the reaction had occurred.