Browsing CHEM Faculty Scholarship by Author "Araki, Yasuyaki"
Now showing items 1-15 of 15
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Design and studies on supramolecular ferrocene-porphyrin-fullerene constructs for generating long-lived charge separated states
D'Souza, Francis; Chitta, Raghu; Gadde, Suresh; Islam, D-M Shafiqul; Schumacher, Amy Lea; Zandler, Melvin E.; Araki, Yasuyaki; Ito, Osamu (American Chemical Society, 2006-12-21)Supramolecular ferrocene-porphyrin-fullerene constructs, in which covalently linked ferrocene-porphyrin-crown ether compounds were self-assembled with alkylammonium cation functionalized fullerenes, have been designed to ... -
Design, syntheses, and studies of supramolecular porphyrin-fullerene conjugates, using bis-18-crown-6 appended porphyrins and pyridine or alkyl ammonium functionalized fullerenes
D'Souza, Francis; Chitta, Raghu; Gadde, Suresh; McCarty, Amy L.; Karr, Paul A.; Zandler, Melvin E.; Sandanayaka, Atula S. D.; Araki, Yasuyaki; Ito, Osamu (American Chemical Society, 2006-03-30)Photoinduced electron-transfer processes in cis and trans functionalized bis-18-crown-6 porphyrin self-assembled with fullerene functionalized with pyridine or alkylammonium cation entities are reported. The structural ... -
Effect of axial ligation or pi-pi-type interactions on photochemical charge stabilization in "two-point" bound supramolecular porphyrin-fullerene conjugates
D'Souza, Francis; Chitta, Raghu; Gadde, Suresh; Zandler, Melvin E.; McCarty, Amy L.; Sandanayaka, Atula S. D.; Araki, Yasuyaki; Ito, Osamu (John Wiley and Sons, 2005-07-18)Two types of structurally well-defined, self-assembled zinc porphyrin-fullerene conjugates were formed by "two-point" binding strategies to probe the effect of axial ligation or pi-pi-type interactions on the photochemical ... -
Energy transfer followed by electron transfer in a supramolecular triad composed of boron dipyrrin, zinc porphyrin, and fullerene: a model for the photosynthetic antenna-reaction center complex
D'Souza, Francis; Smith, Phillip M.; Zandler, Melvin E.; McCarty, Amy L.; Itou, Mitsunari; Araki, Yasuyaki; Ito, Osamu (American Chemical Society, 2004-06-30)The first example of a working model of the photosynthetic antenna-reaction center complex, constructed via self-assembled supramolecular methodology, is reported. For this, a supramolecular triad is assembled by axially ... -
Formation, spectral, electrochemical, and photochemical behavior of zinc N-confused porphyrin coordinated to imidazole functionalized fullerene dyads
D'Souza, Francis; Smith, Phillip M.; Rogers, Lisa M.; Zandler, Melvin E.; Islam, D-M Shafiqul; Araki, Yasuyaki; Ito, Osamu (American Chemical Society, 2006-06-26)Donor-acceptor dyads were constructed using zinc N-confused porphyrin (ZnNCP), a structural isomer of zinc tetraphenylporphyrin, as a donor, and fullerene as an electron acceptor. Two derivatives, pyridine-coordinated zinc ... -
Multi-triphenylamine-substituted porphyrin-fullerene conjugates as charge stabilizing "antenna-reaction center" mimics
D'Souza, Francis; Gadde, Suresh; Islam, D-M Shafiqul; Wijesinghe, Channa A.; Schumacher, Amy Lea; Zandler, Melvin E.; Araki, Yasuyaki; Ito, Osamu (American Chemical Society, 2007-09-06)A new concept of charge stabilization via delocalization of the pi-cation radical species over the donor macrocycle substituents in a relatively simple donor-acceptor bearing multimodular conjugates is reported. The newly ... -
Photoinduced electron transfer in a Watson-Crick base-paired, 2-aminopurine:uracil-C60 hydrogen bonding conjugate
D'Souza, Francis; Gadde, Suresh; Islam, D-M Shafiqul; Pang, Siew-Cheng; Schumacher, Amy Lea; Zandler, Melvin E.; Horie, Rumiko; Araki, Yasuyaki; Ito, Osamu (Royal Society of Chemistry, 2007-02-07)A fluorescent reporter molecule, 2-aminopurine was self-assembled via Watson-Crick base-pairing to a uracil appended fullerene to form a donor-acceptor conjugate; efficient photoinduced charge separation was confirmed by ... -
Photosynthetic reaction center mimicry of a "special pair" dimer linked to electron acceptors by a supramolecular approach: self-assembled cofacial zinc porphyrin dimer complexed with fullerene(s)
D'Souza, Francis; Chitta, Raghu; Gadde, Suresh; Rogers, Lisa M.; Karr, Paul A.; Zandler, Melvin E.; Sandanayaka, Atula S. D.; Araki, Yasuyaki; Ito, Osamu (John Wiley and Sons, 2007-01-01)Biomimetic bacterial photosynthetic reaction center complexes have been constructed using well-defined self-assembled supramolecular approaches. The "special pair" donor, a cofacial porphyrin dimer, was formed via potassium ... -
Potassium ion controlled switching of intra- to intermolecular electron transfer in crown ether appended free-base porphyrin-fullerene donor-acceptor systems
D'Souza, Francis; Chitta, Raghu; Gadde, Suresh; Zandler, Melvin E.; McCarty, Amy L.; Sandanayaka, Atula S. D.; Araki, Yasuyaki; Ito, Osamu (American Chemical Society, 2006-04-06)Photoinduced electron transfer in intramolecularly interacting free-base porphyrin bearing one or four 18-crown-6 ether units at different positions of the porphyrin macrocycle periphery and pristine fullerene was investigated ... -
Self-assembled single-walled carbon nanotube:zinc-porphyrin hybrids through ammonium ion-crown ether interaction: construction and electron transfer
D'Souza, Francis; Chitta, Raghu; Sandanayaka, Atula S. D.; Subbaiyan, Navaneetha K.; D'Souza, Lawrence; Araki, Yasuyaki; Ito, Osamu (John Wiley and Sons, 2007-01-01)An ammonium ion-crown ether interaction has been successfully used to construct porphyrin-single-walled carbon nanotube (SWNT) donor-acceptor hybrids. The [18]crown-6 to alkyl ammonium ion binding strategy resulted in ... -
Self-assembled via axial coordination magnesium porphyrin-imidazole appended fullerene dyad: spectroscopic, electrochemical, computational, and photochemical studies
D'Souza, Francis; El-Khouly, Mohamed E.; Gadde, Suresh; McCarty, Amy L.; Karr, Paul A.; Zandler, Melvin E.; Araki, Yasuyaki; Ito, Osamu (American Chemical Society, 2005-05-26)Spectroscopic, redox, and electron transfer reactions of a self-assembled donor-acceptor dyad formed by axial coordination of magnesium meso-tetraphenylporphyrin (MgTPP) and fulleropyrrolidine appended with an imidazole ... -
Supramolecular carbon nanotube-fullerene donor-acceptor hybrids for photoinduced electron transfer
D'Souza, Francis; Chitta, Raghu; Sandanayaka, Atula S. D.; Subbaiyan, Navaneetha K.; D'Souza, Lawrence; Araki, Yasuyaki; Ito, Osamu (American Chemical Society, 2007-12-26)Photoinduced electron transfer in a self-assembled single-wall carbon nanotube (SWNT)-fullerene(C60) hybrid with SWNT acting as an electron donor and fullerene as an electron acceptor has been successfully demonstrated. ... -
Supramolecular complex composed of a covalently linked zinc porphyrin dimer and fulleropyrrolidine bearing two axially coordinating pyridine entities
D'Souza, Francis; Gadde, Suresh; Zandler, Melvin E.; Itou, Mitsunari; Araki, Yasuyaki; Ito, Osamu (Royal Society of Chemistry, 2004-10-21)A zinc porphyrin dimer-fullerene supramolecular complex with a large association constant is assembled; efficient intramolecular photoinduced electron transfer from the singlet excited state of zinc porphyrin to the fullerene ... -
Supramolecular porphyrin-fullerene via 'two-point' binding strategy: axial-coordination and cation-crown ether complexation
D'Souza, Francis; Chitta, Raghu; Gadde, Suresh; Zandler, Melvin E.; Sandanayaka, Atula S. D.; Araki, Yasuyaki; Ito, Osamu (Royal Society of Chemistry, 2005-03-14)A highly stable porphyrin-fullerene conjugate with defined distance and orientation, was formed using a newly developed 'two-point' binding strategy involving axial-coordination and cation-crown ether complexation; ... -
Supramolecular triad and pentad composed of zinc-porphyrin(s), oxoporphyrinogen, and fullerene(s): design and electron-transfer studies
Schumacher, Amy Lea; Sandanayaka, Atula S. D.; Hill, Jonathan P.; Ariga, Katsuhiko; Karr, Paul A.; Araki, Yasuyaki; Ito, Osamu; D'Souza, Francis (John Wiley and Sons, 2007-01-01)By adopting a "covalent-coordinate" bonding approach, novel supramolecular pentad and triad molecules composed of zinc-porphyrin(s), fullerene(s), and oxoporphyrinogen redox-/photoactive entities have been constructed, and ...