@misc{lindsey_muthukumaran_sharada_muresan_youngblood_2008, title={Metal complexation of 1-acyldipyrromethanes and porphyrins formed therefrom}, volume={7,323,561}, number={2008 Jan. 29}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Lindsey, J. S. and Muthukumaran, K. and Sharada, D. S. and Muresan, A. Z. and Youngblood, W. J.}, year={2008} }
 @article{youngblood_2006, title={Synthesis of a new trans-A(2)B(2) phthalocyanine motif as a building block for rodlike phthalocyanine polymers}, volume={71}, DOI={10.1021/jo0521221}, number={9}, journal={Journal of Organic Chemistry}, author={Youngblood, W. J.}, year={2006}, pages={3345–3356} }
 @article{padmaja_youngblood_wei_bocian_lindsey_2006, title={Triple-decker sandwich compounds bearing compact triallyl tripods for molecular information storage applications}, volume={45}, ISSN={["1520-510X"]}, DOI={10.1021/ic060387s}, abstractNote={The design of redox-active molecules that afford multistate operation and high charge density is essential for molecular information storage applications. Triple-decker sandwich compounds composed of two lanthanide metal ions and three porphyrinic ligands exhibit a large number of oxidation states within a relatively narrow electrochemical window. High charge density requires a small footprint upon tethering triple deckers to an electroactive surface. All triple deckers examined to date for information storage have been tethered via the terminal ligand and have exhibited large footprints (approximately 670 A2). Five new homonuclear (Eu or Ce) triple deckers have been prepared (via statistical or rational methods) to examine the effect of tether attachment site on molecular footprint. Three triple deckers are tethered via the terminal ligand (porphyrin) or central ligand (porphyrin or imidazophthalocyanine), whereas two triple deckers each bear two tethers, one at each terminal ligand. The tether is a compact triallyl tripod. Monolayers of the triple deckers on Si(100) were examined by electrochemical and FTIR techniques. Each triple decker exhibited the expected four resolved voltammetric waves, owing to formation of the mono-, di-, tri-, and tetracations. The electrochemical studies of surface coverage (gamma, obtained by integrating the voltammetric waves) reveal that coverages approaching 10(-10) mol cm(-2), corresponding to a molecular footprint of approximately 170 A2, are readily achieved for all five of the triple deckers. The surface coverage observed for the tripodal functionalized triple deckers is approximately 4-fold higher than that obtained for monopodal-functionalized triple deckers (carbon, oxygen, or sulfur anchor atoms) attached to either Si(100) or Au(111). The fact that similar, relatively high, surface coverages can be achieved regardless of the location (or number) of the tripodal tether indicates that the tripodal functionalization, rather than the location of the tether, is the primary determinant of the packing density.}, number={14}, journal={INORGANIC CHEMISTRY}, author={Padmaja, Kisari and Youngblood, W. Justin and Wei, Lingyun and Bocian, David F. and Lindsey, Jonathan S.}, year={2006}, month={Jul}, pages={5479–5492} }
 @article{kee_kirmaier_yu_thamyongkit_youngblood_calder_ramos_noll_bocian_scheidt_et al._2005, title={Structural control of the photodynamics of boron-dipyrrin complexes}, volume={109}, ISSN={["1520-5207"]}, DOI={10.1021/jp0525078}, abstractNote={Boron-dipyrrin chromophores containing a 5-aryl group with or without internal steric hindrance toward aryl rotation have been synthesized and then characterized via X-ray diffraction, static and time-resolved optical spectroscopy, and theory. Compounds with a 5-phenyl or 5-(4-tert-butylphenyl) group show low fluorescence yields (approximately 0.06) and short excited-singlet-state lifetimes (approximately 500 ps), and decay primarily (>90%) by nonradiative internal conversion to the ground state. In contrast, sterically hindered analogues having an o-tolyl or mesityl group at the 5-position exhibit high fluorescence yields (approximately 0.9) and long excited-state lifetimes (approximately 6 ns). The X-ray structures indicate that the phenyl or 4-tert-butylphenyl ring lies at an angle of approximately 60 degrees with respect to the dipyrrin framework whereas the angle is approximately 80 degrees for mesityl or o-tolyl groups. The calculated potential energy surface for the phenyl-substituted complex indicates that the excited state has a second, lower energy minimum in which the nonhindered aryl ring rotates closer to the mean plane of the dipyrrin, which itself undergoes some distortion. This relaxed, distorted excited-state conformation has low radiative probability as well as a reduced energy gap from the ground state supporting a favorable vibrational overlap factor for nonradiative deactivation. Such a distorted conformation is energetically inaccessible in a complex bearing the sterically hindered o-tolyl or mesityl group at the 5-position, leading to a high radiative probability involving conformations at or near the initial Franck-Condon form of the excited state. These combined results demonstrate the critical role of aryl-ring rotation in governing the excited-state dynamics of this class of widely used dyes.}, number={43}, journal={JOURNAL OF PHYSICAL CHEMISTRY B}, author={Kee, HL and Kirmaier, C and Yu, LH and Thamyongkit, P and Youngblood, WJ and Calder, ME and Ramos, L and Noll, BC and Bocian, DF and Scheidt, WR and et al.}, year={2005}, month={Nov}, pages={20433–20443} }
 @article{tamaru_yu_youngblood_muthukumaran_taniguchi_lindsey_2004, title={A tin-complexation strategy for use with diverse acylation methods in the preparation of 1,9-diacyldipyrromethanes}, volume={69}, ISSN={["0022-3263"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0842285782&partnerID=MN8TOARS}, DOI={10.1021/jo035622s}, abstractNote={The acylation of dipyrromethanes to form 1,9-diacyldipyrromethanes is an essential step in the rational synthesis of porphyrins. Although several methods for acylation are available, purification is difficult because 1,9-diacyldipyrromethanes typically streak extensively upon chromatography and give amorphous powders upon attempted crystallization. A solution to this problem has been achieved by reacting the 1,9-diacyldipyrromethane with Bu(2)SnCl(2) to give the corresponding dibutyl(5,10-dihydrodipyrrinato)tin(IV) complex. The reaction is selective for dipyrromethanes that bear acyl groups at both the 1- and 9-positions but otherwise is quite tolerant of diverse substituents. The diacyldipyrromethane-tin complexes are stable to air and water, are highly soluble in common organic solvents, crystallize readily, and chromatograph without streaking. Four methods (Friedel-Crafts, Grignard, Vilsmeier, benzoxathiolium salt) were examined for the direct 1,9-diacylation of a dipyrromethane or the 9-acylation of a 1-acyldipyrromethane. In each case, treatment of the crude reaction mixture with Bu(2)SnCl(2) and TEA at room temperature enabled facile isolation of multigram quantities of the 1,9-diacyldipyrromethane-tin complex. The diacyldipyrromethane-tin complexes could be decomplexed with TFA in nearly quantitative yield. Alternatively, use of a diacyldipyrromethane-tin complex in a porphyrin-forming reaction (reduction with NaBH(4), acid-catalyzed condensation with a dipyrromethane, DDQ oxidation) afforded the desired free base porphyrin in yield comparable to that obtained from the uncomplexed diacyldipyrromethane. The acylation/tin-complexation strategy has been applied to a bis(dipyrromethane) and a porphyrin-dipyrromethane. In summary, the tin-complexation strategy has broad scope, is compatible with diverse acylation methods, and greatly facilitates access to 1,9-diacyldipyrromethanes.}, number={3}, journal={JOURNAL OF ORGANIC CHEMISTRY}, publisher={American Chemical Society (ACS)}, author={Tamaru, S and Yu, LH and Youngblood, WJ and Muthukumaran, K and Taniguchi, M and Lindsey, JS}, year={2004}, month={Feb}, pages={765–777} }
 @article{wei_padmaja_youngblood_lysenko_lindsey_bocian_2004, title={Diverse redox-active molecules bearing identical thiol-terminated tripodal tethers for studies of molecular information storage}, volume={69}, ISSN={["0022-3263"]}, DOI={10.1021/jo0349476}, abstractNote={To examine the effects of molecular structure on charge storage in self-assembled monolayers (SAMs), a family of redox-active molecules has been prepared wherein each molecule bears a tether composed of a tripodal linker with three protected thiol groups for surface attachment. The redox-active molecules include ferrocene, zinc porphyrin, ferrocene-zinc porphyrin, magnesium phthalocyanine, and triple-decker lanthanide sandwich coordination compounds. The tripodal tether is based on a tris[4-(S-acetylthiomethyl)phenyl]-derivatized methane. Each redox-active unit is linked to the methane vertex by a 4,4‘-diphenylethyne unit. The electrochemical characteristics of each compound were examined in solution and in SAMs on Au. Redox-kinetic measurements were also performed on the SAMs (with the exception of the magnesium phthalocyanine) to probe (1) the rate of electron transfer in the presence of an applied potential and (2) the rate of charge dissipation after the applied potential is disconnected. The electrochemical studies of the SAMs indicate that the tripodal tether provides a more robust anchor to the Au surface than does a tether with a single site of attachment. However, the electron-transfer and charge-dissipation characteristics of the two tethers are generally similar. These results suggest that the tripodal tether offers superior stability characteristics without sacrificing electrochemical performance.}, number={5}, journal={JOURNAL OF ORGANIC CHEMISTRY}, author={Wei, LY and Padmaja, K and Youngblood, WJ and Lysenko, AB and Lindsey, JS and Bocian, DF}, year={2004}, month={Mar}, pages={1461–1469} }
 @article{youngblood_gryko_lammi_bocian_holten_lindsey_2002, title={Glaser-mediated synthesis and photophysical characterization of diphenylbutadiyne-linked porphyrin dyads}, volume={67}, ISSN={["1520-6904"]}, DOI={10.1021/jo016150p}, abstractNote={The Pd-mediated Glaser coupling of a zinc monoethynyl porphyrin and a magnesium monoethynyl porphyrin affords a mixture of three 4,4'-diphenylbutadiyne-linked dyads comprised of two zinc porphyrins (Zn-pbp-Zn), two magnesium porphyrins (Mg-pbp-Mg), and one metalloporphyrin of each type (Zn-pbp-Mg). The latter is easily isolated due to the greater polarity of the magnesium versus the zinc chelate. Exposure of Zn-pbp-Mg to silica gel results in selective demetalation, affording Zn-pbp-Fb where Fb = free base porphyrin. This synthesis route employs the magnesium porphyrin as a latent form of the Fb porphyrin, thereby avoiding copper insertion during the Glaser reaction, and as a polar entity facilitating separation. The absorption spectrum of Zn-pbp-Mg or Zn-pbp-Fb is the sum of the spectra of the component parts, while in each case the fluorescence spectrum upon illumination of the Zn porphyrin is dominated by emission from the Mg or Fb porphyrin. Time-resolved absorption spectroscopy shows that the energy-transfer rate constants are (11 ps)(-1) and (37 ps)(-1) for Zn-pbp-Mg and Zn-pbp-Fb, respectively, corresponding to energy-transfer quantum yields of 0.995 and 0.983, respectively. The calculated Förster through-space rates are (1900 ps)(-1) and (1100 ps)(-1) for Zn-pbp-Mg and Zn-pbp-Fb, respectively. Accordingly, the through-bond process dominates for both dyads with a through-bond:through-space energy-transfer ratio of > or =97:1. Collectively, the studies show that the 4,4'-diphenylbutadiynyl linker supports fast and efficient energy transfer between Zn and Mg or Fb porphyrins.}, number={7}, journal={JOURNAL OF ORGANIC CHEMISTRY}, author={Youngblood, WJ and Gryko, DT and Lammi, RK and Bocian, DF and Holten, D and Lindsey, JS}, year={2002}, month={Apr}, pages={2111–2117} }
 @article{loewe_tomizaki_youngblood_bo_lindsey_2002, title={Synthesis of perylene-porphyrin building blocks and rod-like oligomers for light-harvesting applications}, volume={12}, ISSN={["1364-5501"]}, DOI={10.1039/b205680a}, abstractNote={We present the synthesis of four perylene–porphyrin building blocks for use in Glaser, Sonogashira, or Suzuki polymerizations. The building blocks bear synthetic handles (4-ethynylphenyl, 4-iodophenyl, bromo) at the trans 
(5,15) 
meso-positions of a zinc porphyrin and contain two or four perylene-monoimide dyes attached at the 3,5-positions of the non-linking meso-aryl rings of the porphyrin. Each perylene-monoimide bears three 4-tert-butylphenoxy substituents (at the 1-, 6-, and 9-positions) and two isopropyl groups (on the N-aryl unit) for increased solubility. In each case the intervening linker is a diarylethyne unit that bridges the N-imide position of the perylene and the meso-position of the porphyrin. The perylene–porphyrin building blocks were prepared by (1) reaction of a diperylene-dipyrromethane with an aldehyde yielding a trans-A2B2-porphyrin, (2) reaction of a diperylene-aldehyde with a dipyrromethane yielding a trans-A2B2-porphyrin, and (3) reaction of a diperylene-dipyrromethane with a dipyrromethane-dicarbinol yielding a trans-AB2C-porphyrin or ABCD-porphyrin. The building blocks were subjected to Glaser, Sonogashira, or Suzuki coupling conditions in an effort to prepare oligomers containing porphyrins joined via 4,4′-diphenylbutadiyne (dpb), 4,4′-diphenylethyne (dpe), or 1,4-phenylene linkers (p), respectively. Each porphyrin in the backbone bears two or four pendant perylene-monoimide dyes. The Glaser and Sonogashira reactions afforded a distribution of oligomers, whereas the Suzuki reaction was unsuccessful. The oligomers were soluble in solvents such as toluene, THF, or CHCl3 enabling routine handling. The use of perylenes results in (1) increased light-harvesting efficiency particularly in the green spectral region where porphyrins are relatively transparent and (2) greater solubility than is achieved with the use of porphyrins alone. The soluble perylene–porphyrin oligomers are attractive for use as light-harvesting materials in molecular-based solar cells.}, number={12}, journal={JOURNAL OF MATERIALS CHEMISTRY}, author={Loewe, RS and Tomizaki, K and Youngblood, WJ and Bo, ZS and Lindsey, JS}, year={2002}, pages={3438–3451} }