@misc{kirmaier_yang_prathapan_miller_diers_bocian_lindsey_holten_2002, title={Synthesis and excited-state photodynamics of perylene-porphyrin dyads. 4. Ultrafast charge separation and charge recombination between tightly coupled units in polar media}, volume={28}, ISSN={["0922-6168"]}, DOI={10.1163/15685670260469384}, abstractNote={New perylene-porphyrin dyads that have excellent light-harvesting and energy-utilization capabilities in nonpolar media are found to exhibit efficient, ultrafast and tunable charge-transfer activity in polar media. The dyads consist of a perylene-monoimide dye (PMI) connected to a porphyrin (Por) via an ethynylphenyl (ep) linker. The porphyrin constituent of the PMI-ep-Por arrays is either a zinc or magnesium complex (Por = Zn or Mg) or a free-base form (Por = Fb). Following excitation of the perylene in each array in acetonitrile, PMI* decays in ≤0.4 ps by a combination of energy transfer to the ground-state porphyrin (forming Por*) and hole transfer (forming PMI-Por+). The excited porphyrin formed by energy transfer (or via direct excitation) then undergoes effectively quantitative electron transfer back to the perylene (τ = 1, 1, 700 ps for Por = Mg, Zn, Fb). Subsequently, charge recombination within PMI- Por+ returns each dyad quantitatively to the ground state (τ = 2, 4, 8 ps for Por = Mg, Zn, Fb). The dynamics of the PMI Por* → PMI-Por+ and PMI- Por+ → PMI Por charge-transfer processes can be modulated by altering the type of polar solvent (acetonitrile, benzonitrile, tetrahydrofuran and 2,6-lutidine). The charge-separation times for PMI-ep-Zn are 1, 6, 9 and 22 ps in these solvents, while the charge-recombination times are 4, 24, 38 and 34 ps. The efficient, rapid and tunable nature of the charge-transfer processes in polar media makes the PMI-ep-Por dyads useful units for performing molecular-switching functions. These properties when combined with the excellent light-harvesting and energy-transfer capabilities of the same arrays in nonpolar media afford a robust perylene-porphyrin motif that can be tailored for a variety of functions in molecular optoelectronics.}, number={7-9}, journal={RESEARCH ON CHEMICAL INTERMEDIATES}, author={Kirmaier, C and Yang, SI and Prathapan, S and Miller, MA and Diers, JR and Bocian, DF and Lindsey, JS and Holten, D}, year={2002}, pages={719–740} }
 @article{yang_prathapan_miller_seth_bocian_lindsey_holten_2001, title={Synthesis and excited-state photodynamics in perylene-porphyrin dyads 2. Effects of porphyrin metalation state on the energy-transfer, charge-transfer, and deactivation channels}, volume={105}, ISSN={["1089-5647"]}, DOI={10.1021/jp010336a}, abstractNote={The photophysical properties of two perylene−porphyrin dyads have been examined in detail with the aim of expanding the functional utility of these constructs for molecular optoelectronics applications. The dyads consist of a perylene-bis(imide) dye (PDI) connected to either a magnesium porphyrin (Mg) or a free base porphyrin (Fb) via a diphenylethyne (pep) linker. The photophysical behavior of these two dyads show both similarities and differences to one another and to the dyad containing a zinc porphyrin (Zn) that was examined in the previous paper in this series. In the case of both PDI−pep−Fb and PDI−pep−Mg in toluene, the excited perylene unit (PDI*) decays rapidly (Fb = 2.9 ps; Mg = 2.5 ps) by energy transfer to the porphyrin forming PDI−pep−Por* in relatively high yield (Fb ∼ 85%; Mg ∼ 50%) and hole transfer to the porphyrin forming PDI-−pep−Por+ (Fb ∼ 15%; Mg ∼ 50%). This behavior parallels that observed for PDI−pep−Zn, for which rapid (2.5 ps) decay of PDI* affords PDI−pep−Zn* and PDI-−pep−Por+ w...}, number={34}, journal={JOURNAL OF PHYSICAL CHEMISTRY B}, author={Yang, SI and Prathapan, S and Miller, MA and Seth, J and Bocian, DF and Lindsey, JS and Holten, D}, year={2001}, month={Aug}, pages={8249–8258} }
 @article{prathapan_yang_seth_miller_bocian_holten_lindsey_2001, title={Synthesis and excited-state photodynamics of perylene-porphyrin dyads. 1. Parallel energy and charge transfer via a diphenylethyne linker}, volume={105}, ISSN={["1089-5647"]}, DOI={10.1021/jp010335i}, abstractNote={The photophysical properties of a perylene−porphyrin dyad have been examined with the aim of using this construct for molecular photonics applications. The dyad consists of a perylene-bis(imide) dye (PDI) connected to a zinc porphyrin (Zn) via a diphenylethyne linker (pep). In both polar and nonpolar solvents, the photoexcited perylene unit (PDI*) decays very rapidly (lifetimes of 2.5 (toluene) and 2.4 ps (acetonitrile)) by energy transfer to the porphyrin, forming PDI−pep−Zn* in high yield (80%, toluene; 70% acetonitrile), and hole transfer to the porphyrin, forming PDI-−pep−Zn+ in lesser yield (20%, toluene; 30% acetonitrile). In both toluene and acetonitrile, the Zn* excited state subsequently decays with a lifetime of 0.4 ns primarily (80%) by electron transfer to the perylene (forming PDI-−pep−Zn+). In the nonpolar solvent (toluene), the PDI-−pep−Zn+ charge-transfer product has a lifetime of >10 ns and decays by charge recombination primarily to the ground state but also by thermal repopulation of th...}, number={34}, journal={JOURNAL OF PHYSICAL CHEMISTRY B}, author={Prathapan, S and Yang, SI and Seth, J and Miller, MA and Bocian, DF and Holten, D and Lindsey, JS}, year={2001}, month={Aug}, pages={8237–8248} }
 @article{yang_lammi_prathapan_miller_seth_diers_bocian_lindsey_holten_2001, title={Synthesis and excited-state photodynamics of perylene-porphyrindyads. Part 3, Effects of perylene, linker, and connectivity on ultrafast energy transfer}, volume={11}, DOI={10.1039/b102741g}, abstractNote={New perylene–porphyrin dyads have been designed that exhibit superior light-harvesting and energy-utilization activity compared with earlier generations of structurally related dyads. The new dyads consist of a perylene mono(imide) dye (PMI) connected to a porphyrin (Por) 
via an ethynylphenyl (ep) linker. The PMI–ep–Por arrays were prepared with the porphyrin as either a zinc or magnesium complex (Por = Zn or Mg) or a free-base form (Por = Fb). The absorption properties of the perylene complement those of the porphyrin. Following excitation of the perylene (forming PMI*) in toluene, each array exhibits ultrafast (kENT ≥ (0.5 ps)−1) and essentially quantitative energy transfer from PMI* to the ground-state porphyrin (forming Por*). In each 
of the arrays, the properties of the excited porphyrin (lifetime, fluorescence yield, etc.) are basically unperturbed from those of the isolated pigment. Thus, following energy transfer, the excited porphyrin is not quenched by deleterious reactions involving the perylene accessory unit that would otherwise limit the ability of Por* to emit light or transfer energy to another stage in a molecular photonic device. Collectively, the PMI–ep–Por dyads represent the successful result of a molecular design strategy to produce arrays with excellent properties for use as light-input and energy-transduction elements for applications in molecular optoelectronics.}, number={10}, journal={Journal of Materials Chemistry}, author={Yang, S. I. and Lammi, R. K. and Prathapan, S. and Miller, M. A. and Seth, J. and Diers, J. R. and Bocian, D. F. and Lindsey, Jonathan and Holten, D.}, year={2001}, pages={2420–2430} }
 @article{miller_lammi_prathapan_holten_lindsey_2000, title={A tightly coupled linear array of perylene, bis(porphyrin), and phthalocyanine units that functions as a photoinduced energy-transfer cascade}, volume={65}, ISSN={["1520-6904"]}, DOI={10.1021/jo0007940}, abstractNote={We have prepared a linear array of chromophores consisting of a perylene input unit, a bis(free base porphyrin) transmission unit, and a free base phthalocyanine output unit for studies in artificial photosynthesis and molecular photonics. The synthesis involved four stages: (1) a rational synthesis of trans-AB2C-porphyrin building blocks each bearing one meso-unsubstituted position, (2) oxidative, meso,meso coupling of the zinc porphyrin monomers to afford a bis(zinc porphyrin) bearing one phthalonitrile group and one iodophenyl group, (3) preparation of a bis(porphyrin)-phthalocyanine array via a mixed cyclization involving the bis(free base porphyrin) and 4-tert-butylphthalonitrile, and (4) Pd-mediated coupling of an ethynylperylene to afford a perylene-bis(porphyrin)-phthalocyanine linear array. The perylene-bis(porphyrin)-phthalocyanine array absorbs strongly across the visible spectrum. Excitation at 490 nm, where the perylene absorbs preferentially, results in fluorescence almost exclusively from the phthalocyanine (phi(f) = 0.78). The excited phthalocyanine forms with time constants of 2 ps (90%) and 13 ps (10%). The observed time constants resemble those of corresponding phenylethyne-linked dyads, including a perylene-porphyrin (< or = 0.5 ps) and a porphyrin-phthalocyanine (1.1 ps (70%) and 8 ps (30%)). The perylene-bis(porphyrin)-phthalocyanine architecture exhibits efficient light-harvesting properties and rapid funneling of energy in a cascade from perylene to bis(porphyrin) to phthalocyanine.}, number={20}, journal={JOURNAL OF ORGANIC CHEMISTRY}, author={Miller, MA and Lammi, RK and Prathapan, S and Holten, D and Lindsey, JS}, year={2000}, month={Oct}, pages={6634–6649} }
 @article{cho_kim_littler_miller_lee_lindsey_1999, title={Rational synthesis of trans-substituted porphyrin building blocks containing one sulfur or oxygen atom in place of nitrogen at a designated site}, volume={64}, ISSN={["0022-3263"]}, DOI={10.1021/jo9909305}, abstractNote={The use of heteroatom-substituted porphyrins in bioorganic and materials chemistry requires the ability to position a variety of substituents in a controlled manner about the porphyrin periphery. We describe a rational route to trans-AB2C-type porphyrins bearing one oxygen atom (N3O) or one sulfur atom (N3S) in a designated location in the porphyrin core. The synthesis involved four stages:  (1) Acid-catalyzed condensation of a furyl- or thienylcarbinol in excess pyrrole afforded the aryl-substituted furyl- or thienylpyrromethane in high yield. (2) Treatment of the furyl- or thienylpyrromethane with an acid chloride catalyzed by SnCl4 or AlCl3 afforded the corresponding diketo product. (3) Reduction with NaBH4 in alcoholic solvents gave the furyl- or thienylpyrromethanediols. (4) Reaction of a furylpyrromethanediol, thienylpyrromethanediol, or dipyrromethanediol with a dipyrromethane in a one-flask process of condensation followed by oxidation gave the corresponding porphyrin. Reaction conditions previous...}, number={21}, journal={JOURNAL OF ORGANIC CHEMISTRY}, author={Cho, WS and Kim, HJ and Littler, BJ and Miller, MA and Lee, CH and Lindsey, JS}, year={1999}, month={Oct}, pages={7890–7901} }