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1.
Rational Molecular Design towards Vis/NIR Absorption and Fluorescence by using Pyrrolopyrrole aza‐BODIPY and its Highly Conjugated Structures for Organic Photovoltaics
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Prof. Dr. Soji Shimizu Taku Iino Prof. Dr. Akinori Saeki Prof. Dr. Shu Seki Prof. Dr. Nagao Kobayashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(7):2893-2904
Pyrrolopyrrole aza‐BODIPY (PPAB) developed in our recent study from diketopyrrolopyrrole by titanium tetrachloride‐mediated Schiff‐base formation reaction with heteroaromatic amines is a highly potential chromophore due to its intense absorption and fluorescence in the visible region and high fluorescence quantum yield, which is greater than 0.8. To control the absorption and fluorescence of PPAB, particularly in the near‐infrared (NIR) region, further molecular design was performed using DFT calculations. This results in the postulation that the HOMO–LUMO gap of PPAB is perturbed by the heteroaromatic moieties and the aryl‐substituents. Based on this molecular design, a series of new PPAB molecules was synthesized, in which the largest redshifts of the absorption and fluorescence maxima up to 803 and 850 nm, respectively, were achieved for a PPAB consisting of benzothiazole rings and terthienyl substituents. In contrast to the sharp absorption of PPAB, a PPAB dimer, which was prepared by a cross‐coupling reaction of PPAB monomers, exhibited panchromatic absorption across the UV/Vis/NIR regions. With this series of PPAB chromophores in hand, a potential application of PPAB as an optoelectronic material was investigated. After identifying a suitable PPAB molecule for application in organic photovoltaic cells based on evaluation using time‐resolved microwave conductivity measurements, a maximized power conversion efficiency of 1.27 % was achieved. 相似文献
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1,3-Di-tert-butylazulene reacted with highly electrophilic trifluoromethanesulfonate of N-containing heterocycles to give 5-(dihydroheteroaryl)azulene derivatives in good yield and treatment of the 5-(dihydroheteroaryl)azulene derivatives with KOH afforded 5-(heteroaryl)azulenes in excellent yield. 相似文献
4.
Kentaro Suzuki Taro Toyota Katsuhiko Sato Masakazu Iwasaka Shoogo Ueno Tadashi Sugawara 《Chemical physics letters》2007,440(4-6):286-290
Collagen-containing tubular giant vesicles (Col–tGVs) under a high static magnetic field were found to constitute characteristic curved structures (e.g. circular, 8-figure, and hairpin-loop), which were sustained by polymerization of collagen units inside the tGV. We ascribed the formation of these structures to the elasticity of the tGV and to the competing diamagnetic anisotropies between collagen and the tGV. These curved structures can be well expressed by the equation of elastica. 相似文献
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The title racemate-to-conglomerate transformation which occurs in the solid state on heating or contact with MeOH vapour has been studied by IR and DTA spectral measurements, microscopic observation, and by X-ray structural and X-ray powder diffraction analysis. 相似文献
6.
Akinori Furutani 《Tetrahedron letters》2004,45(41):7621-7624
The diastereoselective [2+2] photocycloaddition of a cyclohexenonecarboxylate containing (−)-8-(4-nitrophenyl)menthyl as a chiral auxiliary to ethylene gave the photocycloadduct, a bicyclo[4.2.0]octanone derivative, with a high degree of diastereoselectivity. A photoreaction, conducted in CH2Cl2 at −78 °C gave the corresponding photocycloadduct in 88% de. In the presence of Ti(OR)4 or Me3SnCl, the diastereoselectivity was increased up to 92% de. 相似文献
7.
Akinori Ohshita Masaaki Okuhara Chiharu Matsuya Koichi Hata Kazuo Iida 《Mikrochimica acta》2006,155(1-2):225-228
A new electron holographic method is presented to directly visualize pure phase objects such as electromagnetic microfields,
which is achieved by superposition of two kinds of electron holograms. The method is very simple and is twice as sensitive
as the conventional double-exposure electron holography and the four-electron-wave interference. Using this technique, an
electric field around a charged latex sphere and a magnetic field around a barium ferrite particle have been directly observed. 相似文献
8.
[reaction: see text] The enantioselective total synthesis of (+)-allocyathin B(2) has been achieved. Our approach features a convergent enantioselective construction of the 5-6-7 tricyclic core system using the originally developed chiral building blocks via asymmetric catalysis, the intramolecular aldol reaction in high yield, successful samarium diiodide-mediated ring expansion, and a newly developed double-bond installation method. 相似文献
9.
Andrzej W. Trochimczuk Shoji AokiKazunori Yamabe Akinori Jyo 《European Polymer Journal》2002,38(5):941-945
Four porous vinylnaphthalene/divinylnaphthalene (VN/DVN) polymers having three different nominal crosslinking degrees (60, 80 and 100 wt.%) have been synthesized using the suspension polymerization method in the presence of toluene and decane.The use of various crosslinking levels and inert diluents was aimed at changing the extent of polymeric network-diluent interactions. The resultant polymers have specific surface area in the range 450-700 m2/g depending on the DVN content. Two sets of pores were detected in all resins: one with the diameter of ≈2 nm and the second one in the range of 30-40 nm. Their sorptive properties have been studied using dilute (0.5 mmol/l) solutions of phenol and its derivatives (o-chlorophenol, 2-methylphenol, o-nitrophenol, m-nitrophenol and p-nitrophenol). It has been found that sorption, at low equilibrium concentration, follows the order: o-nitrophenol > o-chlorophenol > m-nitrophenol > o-methylphenol > p-nitrophenol > phenol. Full characteristics of the porous structure of resultant polymers was obtained by nitrogen adsorption at 77 K and their surface properties analyzed using Inverse Gas Chromatography. 相似文献
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