651302-01-1Relevant academic research and scientific papers
Porphyrins Bearing Mono or Tripodal Benzylphosphonic Acid Tethers for Attachment to Oxide Surfaces
Loewe, Robert S.,Ambroise, Arounaguiry,Muthukumaran, Kannan,Padmaja, Kisari,Lysenko, Andrey B.,Mathur, Guru,Li, Qiliang,Bocian, David F.,Misra, Veena,Lindsey, Jonathan S.
, p. 1453 - 1460 (2004)
The ability to attach redox-active molecules to oxide surfaces in controlled architectures (distance, orientation, packing density) is essential for the design of a variety of molecular-based information storage devices. We describe the synthesis of a series of redox-active molecules wherein each molecule bears a benzylphosphonic acid tether. The redox-active molecules include zinc porphyrins, a cobalt porphyrin, and a ferrocene-zinc porphyrin. An analogous tripodal tether has been prepared that is based on a tris [4-(dihydroxyphosphorylmethyl)phenyl]-derivatized methane. A zinc porphyrin is linked to the methane vertex by a 1,4-phenylene unit. The tripodal systems are designed to improve monolayer stability and ensure vertical orientation of the redox-active porphyrin on the electroactive surface. For comparison purposes, a zinc porphyrin bearing a hexylphosphonic acid tether also has been prepared. The synthetic approaches for introduction of the phosphonic acid group include derivatization of a bromoalkyl porphyrin or use of a dimethyl or diethyl phosphonate substituted precursor in a porphyrin-forming reaction. The latter approach makes use of dipyrromethane building blocks bearing mono or tripodal dialkyl phosphonate groups. The zinc porphyrintripodal compound bearing benzylphosphonic acid legs tethered to a SiO2 surface (grown on doped Si) was electrically well-behaved and exhibited characteristic porphyrin oxidation/reduction waves. Collectively, a variety of porphyrinic molecules can now be prepared with tethers of different length, composition, and structure (mono or tripodal) for studies of molecular-based information storage on oxide surfaces.
Synthesis of phosphono-substituted porphyrin compounds for attachment to metal oxide surfaces
-
Page/Page column 16; 24, (2008/06/13)
A method of making a phosphono-substituted dipyrromethane comprises reacting an aldehyde or acetal having at least one phosphono group substituted thereon with pyrrole to produce a phosphono-substituted dipyrromethane; and wherein the phosphono is selecte
