@misc{lindsey_loewe_muthukumaran_ambroise_2009, title={Synthesis of phosphono-substituted porphyrin compounds for attachment to metal oxide surfaces}, volume={7,553,977}, number={2009 Jun 30}, author={Lindsey, J. S. and Loewe, R. S. and Muthukumaran, K. and Ambroise, A.}, year={2009} }
 @article{hindin_forties_loewe_ambroise_kirmaier_bocian_lindsey_holten_knox_2004, title={Excited-state energy flow in covalently linked multiporphyrin arrays: The essential contribution of energy transfer between nonadjacent chromophores}, volume={108}, ISSN={["1520-6106"]}, DOI={10.1021/jp047803j}, abstractNote={A series of multiporphyrin arrays has been studied to probe the contribution of energy transfer between second-neighbor ("nonadjacent") porphyrins and to determine the rate of energy transfer between identical porphyrins at adjacent sites. The arrays, organized in linear or branched architectures, contain up to 21 constituents, domains of 2-5 zinc porphyrins, and a single energy trap. The study has involved iterative cycles of molecular design, synthesis, determination of rates via transient absorption spectroscopy, and kinetic analysis. A rate constant of (30 ′ 10 ps) - 1 is deduced for bidirectional energy transfer between adjacent zinc porphyrins joined by a diphenylethyne linker. The value is (50 ′ 10 ps) - 1 when the porphyrin-linker internal rotation is hindered by o,o'-methyl groups on one aryl ring of the linker. Rates of nonadjacent energy transfers are typically only 5-10-fold less than the rates of adjacent transfers. Thus, the nonadjacent pathway has a significant impact on the overall rate of energy flow to the trap, even in architectures as small as triads. These findings provide information that will be essential for the rational design of multichromophore arrays whose function is to transfer excitation energy efficiently over large distances to a trap site.}, number={34}, journal={JOURNAL OF PHYSICAL CHEMISTRY B}, author={Hindin, E and Forties, RA and Loewe, RS and Ambroise, A and Kirmaier, C and Bocian, DF and Lindsey, JS and Holten, D and Knox, RS}, year={2004}, month={Aug}, pages={12821–12832} }
 @article{muthukumaran_loewe_ambroise_tamaru_li_mathur_bocian_misra_lindsey_2004, title={Porphyrins bearing arylphosphonic acid tethers for attachment to oxide surfaces}, volume={69}, ISSN={["0022-3263"]}, DOI={10.1021/jo034945l}, abstractNote={Synthetic molecules bearing phosphonic acid groups can be readily attached to oxide surfaces. As part of a program in molecular-based information storage, we have developed routes for the synthesis of diverse porphyrinic compounds bearing phenylphosphonic acid tethers. The routes enable (1) incorporation of masked phosphonic acid groups in precursors for use in the rational synthesis of porphyrinic compounds and (2) derivatization of porphyrins with masked phosphonic acid groups. The precursors include dipyrromethanes, monoacyldipyrromethanes, and diacyldipyrromethanes. The tert-butyl group has been used to mask the dihydroxyphosphoryl substituent. The di-tert-butyloxyphosphoryl unit is stable to the range of conditions employed in syntheses of porphyrins and multiporphyrin arrays yet can be deprotected under mild conditions (TMS-Cl/TEA or TMS-Br/TEA in refluxing CHCl(3)) that do not cause demetalation of zinc or magnesium porphyrins. The porphyrinic compounds that have been prepared include (1) A(3)B-, trans-AB(2)C-, and ABCD-porphyrins that bear a single phenylphosphonic acid group, (2) a trans-A(2)B(2)-porphyrin bearing two phenylphosphonic acid groups, (3) a chlorin that bears a single phenylphosphonic acid group, and (4) a porphyrin dyad bearing a single phenylphosphonic acid group. For selected porphyrin-phosphonic acids, the electrochemical characteristics have been investigated for molecules tethered to SiO(2) surfaces grown on doped Si. The voltammetric behavior indicates that the porphyrin-phosphonic acids form robust, electrically well-behaved monolayers on the oxide surface.}, number={5}, journal={JOURNAL OF ORGANIC CHEMISTRY}, author={Muthukumaran, K and Loewe, RS and Ambroise, A and Tamaru, SI and Li, QL and Mathur, G and Bocian, DF and Misra, V and Lindsey, JS}, year={2004}, month={Mar}, pages={1444–1452} }
 @article{loewe_ambroise_muthukumaran_padmaja_lysenko_mathur_li_bocian_misra_lindsey_2004, title={Porphyrins bearing mono or tripodal benzylphosphonic acid tethers for attachment to oxide surfaces}, volume={69}, ISSN={["1520-6904"]}, DOI={10.1021/jo034946d}, abstractNote={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 porphyrin-tripodal compound bearing benzylphosphonic acid legs tethered to a SiO(2) 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.}, number={5}, journal={JOURNAL OF ORGANIC CHEMISTRY}, author={Loewe, RS and Ambroise, A and Muthukumaran, K and Padmaja, K and Lysenko, AB and Mathur, G and Li, QL and Bocian, DF and Misra, V and Lindsey, JS}, year={2004}, month={Mar}, pages={1453–1460} }
 @article{laha_dhanalekshmi_taniguchi_ambroise_lindsey_2003, title={A scalable synthesis of meso-substituted dipyrromethanes}, volume={7}, ISSN={["1520-586X"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0346735296&partnerID=MN8TOARS}, DOI={10.1021/op034083q}, abstractNote={A one-flask synthesis of meso-substituted dipyrromethanes has been refined. The procedure entails reaction of an aldehyde in 100 equiv of pyrrole as the solvent containing a mild Lewis acid (e.g., InCl3) at room temperature. Following removal and recovery of excess pyrrole, the dipyrromethane is obtained by crystallization. The procedure generates minimal waste and does not require aqueous/organic extraction, chromatography, or distillation. The procedure has been scaled linearly to obtain >100 g of 5-phenyldipyrromethane. The utility of various analytical methods for characterizing dipyrromethanes has been investigated.}, number={6}, journal={ORGANIC PROCESS RESEARCH & DEVELOPMENT}, publisher={American Chemical Society (ACS)}, author={Laha, JK and Dhanalekshmi, S and Taniguchi, M and Ambroise, A and Lindsey, JS}, year={2003}, pages={799–812} }
 @article{ambroise_kirmaier_wagner_loewe_bocian_holten_lindsey_2002, title={Weakly coupled molecular photonic wires: Synthesis and excited-state energy-transfer dynamics}, volume={67}, ISSN={["1520-6904"]}, DOI={10.1021/jo025561i}, abstractNote={Molecular photonic wires, which absorb light and undergo excited-state energy transfer, are of interest as biomimetic models for photosynthetic light-harvesting systems and as molecular devices with potential applications in materials chemistry. We describe the stepwise synthesis of four molecular photonic wires. Each wire consists of an input unit, transmission element, and output unit. The input unit consists of a boron-dipyrrin dye or a perylene-monoimide dye (linked either at the N-imide or the C9 position); the transmission element consists of one or three zinc porphyrins affording short or long wires, respectively; and the output unit consists of a free base (Fb) porphyrin. The components in the arrays are joined in a linear architecture via diarylethyne linkers (an ethynylphenyl linker is attached to the C9-linked perylene). The wires have been examined by static absorption, static fluorescence, and time-resolved absorption spectroscopy. Each wire (with the exception of the C9-linked perylene wire) exhibits a visible absorption spectrum that is the sum of the spectra of the component parts, indicating the relatively weak electronic coupling between the components. Excitation of each wire at the wavelength where the input unit absorbs preferentially (typically 480-520 nm) results in emission almost exclusively from the Fb porphyrin. The static emission and time-resolved data indicate that the overall rate constants and quantum efficiencies for end-to-end (i.e., input to output) energy transfer are as follows: perylene-(N-imide)-linked short wire, (33 ps)(-1) and >99%; perylene-(C9)-linked short wire, (26 ps)(-1) and >99%; boron-dipyrrin-based long wire, (190 ps)(-1) and 81%; perylene-(N-imide)-linked long wire, (175 ps)(-1) and 86%. Collectively, the studies provide valuable insight into the singlet-singlet excited-state energy-transfer properties in weakly coupled molecular photonic wires.}, number={11}, journal={JOURNAL OF ORGANIC CHEMISTRY}, author={Ambroise, A and Kirmaier, C and Wagner, RW and Loewe, RS and Bocian, DF and Holten, D and Lindsey, JS}, year={2002}, month={May}, pages={3811–3826} }