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71.
Copper(II)-trifluorothenoylacetone complex in chloroform does not undergo decomposition when scrubbed with sodium hydroxide solution. This allows the complete removal of the residual reagent, and a highly sensitive method for the extraction and spectrophotometric determination of copper(II) results. 相似文献
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Three-component coupling of bis(dialkylamino)chloroborane, alkynes and organozirconium reagents proceeded in the presence of palladium catalysts, leading to the formation of stereo-defined alkenylborane derivatives via cis-carboboration of carbon-carbon triple bonds. 相似文献
76.
On the basis of the boron-masking strategy, new divalent cross-coupling modules have been designed for the efficient synthesis of boron-substituted oligoarenes. The modules, i.e., monoprotected o-, m-, and p-benzenediboronic acid derivatives, undergo highly selective Suzuki-Miyaura coupling with sp2 iodides, bromides, chlorides, and triflates, affording coupling products in which the protected boronyl groups are left intact. 相似文献
77.
Tsukahara S Suehara M Fujiwara T 《Langmuir : the ACS journal of surfaces and colloids》2008,24(5):1673-1677
The dynamics of single giant deoxyribonucleic acid (T4GT7DNA, 165 600 base pairs) molecules was examined near and at the toluene/water, toluene-trioctylamine mixtures/water, and trioctylamine/water interfaces by total internal reflection fluorescence microscopy. The results were considerably affected by the trioctylamine content. With pure toluene or mixtures of lower trioctylamine volume contents (%VA), the randomly coiled DNA molecules diffused to near the interfaces. With mixtures of higher %VA (9 and 50%), the DNA molecules were stretched and adsorbed at the interfaces. There are a large number of anionic phosphate groups ((-O)2PO2-) in the DNA molecule that have an electrostatic affinity to protonated trioctylamine existing at the interface. In the case of pure trioctylamine, globular DNA molecules were adsorbed at the interface and also existed in the aqueous phase. 相似文献
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Prof. Dr. Akio Kamimura Sanshiro Sakamoto Haruka Umemoto Dr. Takuji Kawamoto Dr. Michinori Sumimoto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(62):14081-14088
A new dye was developed, the photoluminescence properties of which are controlled by a chemical reaction. The fluorescence properties of 2-sulfanylhydroquinone dimers depend on the number of hydroxyl groups that are acylated. Unprotected or monoacylated 2-sulfanylhydroquinone dimers displayed good fluorescence properties, whereas diacylated and tetraacylated 2-sulfanylhydroquinone dimers showed dramatically decreased fluorescence. A monomesylated derivative was devised, which shows good fluorescence characteristics as a switching fluorescence dye through a chemical reaction. 相似文献
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Mohammad Shahabuddin Md Jalil Miah Ken-ichi Iimura Takao Kimura Michinori Karikomi 《Tetrahedron letters》2017,58(13):1334-1337
A new class of amphiphilic oxa[9]helicene derivatives were synthesized in excellent-to-fair yields, and successfully characterized by different analytical techniques (e.g., FT-IR, 1H and 13C NMR, and HRMS). The compounds were enantiomerically separated by chiral HPLC and the absolute configurations of the enantiomers were confirmed by circular dichroism spectroscopy. Other optical properties (e.g., UV, photoluminescence, specific optical rotation and molecular optical rotation) of the newly synthesized compounds were also examined. 相似文献