468082-98-6Relevant articles and documents
Synthesis and photophysical properties of light-harvesting arrays comprised of a porphyrin bearing multiple perylene-monoimide accessory pigments
Tomizaki, Kin-ya,Loewe, Robert S.,Kirmaier, Christine,Schwartz, Jennifer K.,Retsek, Jennifer L.,Bocian, David F.,Holten, Dewey,Lindsey, Jonathan S.
, p. 6519 - 6534 (2002)
We present the synthesis and characterization of new light-harvesting arrays containing two, four, or eight perylene-monoimide accessory pigments attached to a zinc porphyrin. Each perylene is substituted with one or three 4-tert-butylphenoxy substituents. A 4,3′- or 4,2′-diarylethyne linker joins the perylene N-imide position and the porphyrin meso-position, affording divergent or convergent architectures, respectively. The architectures are designed to provide high solubility in organic media and facile perylene-to-porphyrin energy transfer, while avoiding charge-transfer quenching of the excited porphyrin product. For the array containing four perylenes per porphyrin in both nonpolar (toluene) and polar (benzonitrile) media and for the array containing eight perylenes per porphyrin in toluene, the photoexcited perylene-monoimide dye (PMI*) decays rapidly (～3.5 ps) and predominantly (≥90%) by energy transfer to the zinc porphyrin to form the excited zinc porphyrin (Zn*), which has excited-state characteristics (lifetime, fluorescence yield) comparable (within ～10%) to those of the isolated chromophore. For the array containing eight perylenes in benzonitrile, PMI* decays ～80% by energy transfer (forming Zn*) and ～20% by hole transfer (forming PMI- Zn+); Zn* subsequently decays ～20% by electron transfer (also forming PMI- Zn+) and ～80% by the normal routes open to the porphyrin monomer (intersystem crossing, internal conversion, fluorescence). In addition to rapid and efficient perylene-to-porphyrin energy transfer, the broad blue-green to yellow absorption of the perylene dyes complements the blue absorption of the porphyrin, resulting in excellent light harvesting across a significant spectral region. Collectively, the work described herein identifies multiperylene-porphyrin arrays that exhibit suitable photochemical properties for use as motifs in larger light-harvesting systems.
Preparation of phenalenes and hydronaphthacenes through tandem alkyne Fischer-carbene complex coupling and inter- or intra-molecular Diels-Alder reactions
Patti, Rajesh Kumar,Duan, Shaofeng,Wang, Zhipeng,Herndon, James W.
supporting information; experimental part, p. 4182 - 4185 (2011/09/19)
The rapid construction of phenalenes through the reaction of 8-alkynyltetralones with Fischer-carbene complexes followed by either an inter- or intra-molecular Diels-Alder reaction is presented. As a showcase of the synthetic utility of this process, the rapid construction of polycyclic ring systems containing the tetracycline core has been demonstrated through an iterative application of this reaction sequence.
