Notes

As part of our photosynthetic model studies in collaboration with Prof
N. UV-Activated Acid Generator , the energy-gap dependence of intramolecular charge separation was examined by exploring the photoexcited dynamics of 1,4-phenylene-bridged hybrid porphyrin dimers. This study required electron-deficient porphyrins in the dimers that could serve as an electron-accepting unit towards an octaalkyl-substituted Zn(II) porphyrin donor. To this end, we employed meso-nitrated porphyrins and meso-pentafluorophenyl porphyrins. Light-Induced Acid Source to prepare these electron-deficient porphyrins allowed us to serendipitously find both a meso-meso-linked porphyrin dimer and a series of meso-pentafluorophenyl-substituted expanded porphyrins. The meso-meso-linked Zn(II) porphyrin dimer was found as a byproduct in the nitration of 5,10-diaryl Zn(II) porphyrin with AgNO2 but became a major product in the reaction with AgPF6.

This finding opened up a new path to directly linked porphyrin oligomers. The series of meso-pentafluorophenyl-substituted expanded porphyrins were prepared via BF3·OEt2-catalyzed condensation of pyrrole and pentafluorobenzaldehyde when the reaction was run at tenfold-higher substrate concentrations, as compared to the optimal conditions for the synthesis of 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin. These expanded porphyrins have been shown to have attractive attributes such as flexible structures, versatile electronic states, multi-metal coordination, anion sensing, and large nonlinear optical properties. While View more were mostly curiosity-driven, some of our work covers rather more general interests: how linearly connected molecules can be rationally synthesized and isolated in a pure and discrete form, how large π-conjugation can be realized to allow for very low energy electronic transitions, and how easily Möbius aromatic and antiaromatic molecules can be cine-Substitution reactions of metallabenzenes: an experimental and Innovation Center of Chemistry for Energy Materials, and College of Chemistry nucleophilic aromatic substitution with MeOH or EtOH to give cine-substitution of strong alkali. However, the reactions of compound 2 with various amines, such as n-butylamine and aniline, afford five-membered ring species, the desired cine-substitution products, [(SCN)2(PPh3)2OsCHC(PPh3)CHCHC(NHR')] reactions have been investigated in detail with the aid of isotopic labeling experiments and density functional theory (DFT) calculations. The results reveal that the cine-substitution reactions occur through nucleophilic addition, dissociation of the leaving group, protonation, and deprotonation steps, which resemble the classical "addition-of-nucleophile, ring-opening, ring-closure" (ANRORC) mechanism. DFT calculations suggest that, in the reaction with MeOH, the formation of a five-membered metallacycle species is both kinetically and thermodynamically less favorable, which is consistent with the experimental results that only the cine-substitution product is observed.

For the analogous reaction with n-butylamine, the pathway for the formation of the cine-substitution product is kinetically less favorable than the pathway for the formation of a five-membered ring species, but is much more thermodynamically favorable, again consistent with the experimental conversion of compound 8 into compound 6, which is observed in an in situ NMR experiment with an isolated pure Enhancing the J(SC) of P3HT-Based OSCs via a Thiophene-Fused Aromatic Heterocycle as a "π-Bridge" for A-π-D-π-A-Type Acceptors.College of Chemistry and Molecular Sciences , Wuhan University , Wuhan 430072 , Poly(3-hexylthiophene) (P3HT)-based organic solar cells (OSCs) have been extensively studied due to unique advantages of P3HT such as roll-to-roll and large-area printing fabrication, but a poor short-circuit current density greatly limits the enhancement of power conversion efficiency (PCE). Herein, via the thiophene-fused aromatic heterocycle as a "π-bridge", two "A-π-D-π-A"-type acceptors have been designed and synthesized for P3HT-based OSCs. The aromaticity of the fused thiophene ring has effectively stabilized the quinoid population, thus strengthening the intramolecular charge transfer and further improving the current density. Owing to the weaker electron-withdrawing ability of the thiophene-fused benzotriazole unit in JC2 than the thiophene-fused benzothiadiazole unit in JC1, a blue-shifted absorption occurs for JC2 to show a better complementarity with P3HT to improve the light-harvesting efficiency and current density of the derived OSCs, and an uplifted lowest unoccupied molecular orbital energy level is also achieved for JC2 to obtain higher voltages. Thus, the P3HT:JC2-based device exhibits a PCE of 64% with a high JSC of 136 mA cm-2 and a VOC of 01 V, significantly exceeding those of the P3HT:JC1 device with a PCE of 20%, a JSC of 106 mA cm-2, and a VOC of 08 V. This indicates that the fusion of a thiophene ring onto a benzotriazole unit is an effective strategy to balance the VOC and JSC of P3HT-based OSCs to achieve excellent Copper 1,19-Diaza-21,24-dicarbacorrole: A Corrole Analogue with an N-N Linkage Stabilizes a Ground-State Singlet Organocopper Species.

Center for Molecular Systems, Kyushu University, Fukuoka, 819-0395, Japan.
Here's my website: http://en.wikipedia.org/wiki/Photoresist