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921.
Synthesis and photovoltaic properties of thieno[3,4‐b]pyrazine or dithieno[3′,2′:3,4;2″,3″:5,6]benzo[1,2‐d]imidazole‐containing conjugated polymers 下载免费PDF全文
Mukhamed L. Keshtov Dmitri Yu. Godovsky Alexei R. Khokhlov Tetsunari Mizobe Hiroyuki Fujita Eisuke Goto Junya Hiyoshi Saki Nakamura Susumu Kawauchi Tomoya Higashihara Tsuyoshi Michinobu 《Journal of polymer science. Part A, Polymer chemistry》2015,53(9):1067-1075
Novel conjugated polymers composed of benzo[1,2‐b:4,5‐b′]dithiophene and thieno[3,4‐b]pyrazine or dithieno[3′,2′:3,4;2″,3″:5,6]benzo[1,2‐d]imidazole units are synthesized by Stille polycondensation. The resulting polymers display a longer wavelength absorption and well‐defined redox activities. The effective intramolecular charge‐transfer and energy levels of all polymers are elucidated by computational calculations. Bulk‐heterojunction solar cells based on these polymers as p‐type semiconductors and [6,6]‐phenyl‐C61‐butyric acid methyl ester (PC61BM) as an n‐type semiconductor are fabricated, and their photovoltaic performances are for the first time evaluated. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1067–1075 相似文献
922.
Yasutaka Nakamura Takumi Nakazato Takuto Kamatsuka Prof. Dr. Hiroshi Shinokubo Prof. Dr. Yoshihiro Miyake 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(45):10571-10574
Reductive aromatization of perylene diimides with acid anhydrides in the presence of Mn or Zn metals provides soluble and planar 2,9-diazaperopyrenes with ester groups at 1,3,8,10-positions. The pivaloxy groups at the peripheral positions can be transformed into a variety of aryl groups through nickel-catalyzed cross-coupling of ester groups. Emission colors of diazaperopyrenes are tunable by the peripheral substituents. The peripheral substituents also affect the aggregation behaviors of 2,9-diazaperopyrenes in the solution and solid states. 相似文献
923.
Dr. Minh Anh Truong Dr. Jaehyun Lee Tomoya Nakamura Dr. Ji-Youn Seo Mina Jung Masashi Ozaki Ai Shimazaki Dr. Nobutaka Shioya Prof. Dr. Takeshi Hasegawa Prof. Dr. Yasujiro Murata Dr. Shaik Mohammed Zakeeruddin Prof. Dr. Michael Grätzel Dr. Richard Murdey Prof. Dr. Atsushi Wakamiya 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(27):6741-6752
A series of two-dimensionally expanded azulene-core-based π systems have been synthesized with different alkyl chain lengths in the alkoxy moieties connected to the partially oxygen-bridged triarylamine skeletons. The thermal, photophysical, and electronic properties of each compound were evaluated to determine the influence of the alkyl chain length on their effectiveness as hole-transporting materials (HTMs) in perovskite solar cells (PSCs). All the synthesized molecules showed promising material properties, including high solubility, the formation of flat and amorphous films, and optimal alignment of energy levels with perovskites. In particular, the derivatives with methyl and n-butyl in the side chains retained amorphous stability up to 233 and 159 °C, respectively. Such short alkoxy chains also resulted in improved electrical device properties. The PSC device fabricated with the HTM with n-butyl side chains showed the best performance with a power conversion efficiency of 18.9 %, which compares favorably with that of spiro-OMeTAD-based PSCs (spiro-OMeTAD=2,2′,7,7′-tetrakis[N,N-bis(p-methoxyphenyl)amino]-9,9′-spirobifluorene). 相似文献
924.
Direct Enantioselective Vinylogous Mannich Reaction of Ketimines with γ‐Butenolide by Using Cinchona Alkaloid Amide/Zinc(II) Catalysts 下载免费PDF全文
Prof. Dr. Shuichi Nakamura Ryota Yamaji Dr. Masashi Hayashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(27):9615-9618
A direct enantioselective vinylogous Mannich reaction of ketimines with γ‐butenolide has been developed. Good yields and enantioselectivities were observed for the reaction of various ketimines by using a cinchona alkaloid amide/Zn(OTf)2 catalyst and Et3N. Both enantiomers of the products could be obtained by using pseudoenantiomeric chiral catalysts. 相似文献
925.
Shunichi Murata Marianna S. Safronova Ulyana I. Safronova Nobuyuki Nakamura 《X射线光谱测定》2020,49(1):200-203
We present visible to near-infrared spectra of highly charged Yb (the atomic number 70) and W (74) obtained with a compact electron beam ion trap. By observing the dependence on the electron beam energy, the charge state that should be assigned to the observed lines is determined. For In-like Yb21+ and W25+ and Sn-like W24+, the experimental spectra are compared with theoretical calculations done by the CI+all-order method. In each spectrum, the most prominent line is identified as the magnetic dipole transition from the first excited fine structure level to the ground level in the ground electronic configuration, 4f3 for In-like ions and 4f4 for Sn-like ions. 相似文献
926.
Dr. Akiko Nakamura Dr. Marwa Abdel Latif Prof. Paul A. Deck Prof. Neal Castagnoli Jr. Prof. James M. Tanko 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(4):823-829
Mechanistic studies with 5-ethyl-3-methyllumiflavinium (Fl+) perchlorate, a biomimetic model for flavoenzyme monoamine oxidase B (MAO-B) catalysis, and the tertiary, allyl amine 1-methyl-4-(1-methyl-1 H-pyrrol-2-yl)-1,2,3,6-tetrahydropyridine (MMTP) reveal that proton-coupled electron transfer (PCET) may be an important pathway for MAO catalysis. The first step involves a single-electron transfer (SET) leading to the free radicals Fl. and MMTP., the latter produced by deprotonation of the initially formed and highly acidic MMTP.+. Molecular oxygen (O2) is found to play a hitherto unrecognized role in the early steps of the oxidation. MMTP and several structurally similar tertiary amines are the only tertiary amines oxidized by MAO, and their structural/electronic properties provide the key to understanding this behavior. A general hypothesis about the role of SET in MAO catalysis, and the recognition that PCET occurs with appropriately substituted substrates is presented. 相似文献
927.
Minoru Yamaji Hideki Okamoto Kenta Goto Shin-ichiro Kato Fumito Tani Yosuke Nakamura 《Tetrahedron letters》2018,59(13):1216-1219
We prepared isomeric compounds 2a and 2b having fused skeletons of coumarin and fluorene by photochemical cyclization of olefin 1. They were successfully separated by chromatography, and characterized by NMR spectroscopic and X-ray crystallographic analyses. The molecular structure of 2a was nonplanar due to the repulsion between the carbonyl group of the coumarin moiety and the methylene group at 9-position on the fluorene skeleton whilst that of 2b was planar. They showed different absorption and fluorescence features in solution whereas their spectral profiles of triplet–triplet absorption and phosphorescence were similar to each other. 相似文献
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