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951.
René Liedtke Sabrina Surmiak Xiaoming Jie Constantin G. Daniliuc Gerald Kehr Gerhard Erker 《Helvetica chimica acta》2021,104(11):e2100149
1,2,4,5-Tetrakis(trimethylsilylethynyl)benzene reacted with two molar equivalents of the boranes R−B(C6F5)2 (R=C6F5, Me, Ph) in a series of sequential 1,1-carboboration reactions to give ca. 1 : 1 mixtures of the two-fold benzannulated products, namely the respective C2h and C2v symmetric tetra-silyl, bis-boryl substituted anthracenes. Their active B(C6F5)2 substituents were used for consecutive Suzuki-Miyaura C−C coupling reactions to give boron-free phenyl or 2-pyridyl substituted anthracene products. 相似文献
952.
Steffen Riebe Dr. Suliman Adam Dr. Bibhisan Roy Dr. Iván Maisuls Dr. Constantin G. Daniliuc Justin Dubbert Prof. Dr. Cristian A. Strassert Prof. Dr. Igor Schapiro Prof. Dr. Jens Voskuhl 《化学:亚洲杂志》2021,16(16):2307-2313
In this contribution, we report on a class of emitters based on bridged oxo- and/or thioethers revealing striking photoluminescence properties in fluid solution and in the solid state. In total, nine compounds were investigated concerning their photophysical properties, which were interpreted by quantum chemical calculations. To our delight, we discovered compounds possessing nearly identical photoluminescence quantum yields (ΦF) in solution and in the solid state, which has been rarely reported so far. Besides these efforts, we shed light on the influence of polymorphism and solvent polarity on the emission properties. In addition, an in-depth X-ray diffractometric analysis was conducted to correlate molecular packing in the crystal with differences in the photophysical properties. 相似文献
953.
954.
Dr. You-Jie Yu Dr. Michael Schäfer Dr. Constantin G. Daniliuc Prof. Dr. Ryan Gilmour 《Angewandte Chemie (International ed. in English)》2023,62(1):e202214906
A catalysis-based regioselective 1,4-fluorofunctionalization of trifluoromethyl substituted 1,3-dienes has been developed to access compact, highly functionalized products. The process allows E,Z-mixed dienes to be processed to a single E-alkene isomer, and leverages an inexpensive and operationally convenient I(I)/I(III) catalysis platform. The first example of catalytic 1,4-difluorination is disclosed and subsequently evolved to enable 1,4-hetero-difunctionalization, which allows δ-fluoro-alcohol and amine derivatives to be forged in a single operation. The protocol is compatible with a variety of nucleophiles including fluoride, nitriles, carboxylic acids, alcohols and even water thereby allowing highly functionalized products, with a stereocenter bearing both C(sp3)−F and C(sp3)−CF3 groups, to be generated rapidly. Scalability (up to 3 mmol), and facile post-reaction modifications are demonstrated to underscore the utility of the method in expanding organofluorine chemical space. 相似文献
955.
956.
957.
François Constantin Françoise Fenouillot Jean-Luc Guillaume Raymond Koenig Jean-Pierre Pascault 《Macromolecular Symposia》2003,198(1):335-344
Properties of thermoplastic modified epoxy network have been studied. The particularity of this work is the use of new thermoplastic epoxies whose structure is close to the final matrix. Blends of thermoset epoxy (Diglycidyl Ether of Bisphenol A/4-4′ methylenebis [3-chloro 2,6-diethylaniline]) with a thermoplastic content from 5 to 40%w have been realised. Initial miscibility in the thermoset precursors shows an UCST behaviour with a maximal value near 130°C for a thermoplastic content of 10%. Due to the presence of tertiary amine and pendant hydroxyl groups on the thermoplastic backbone, epoxy amine reactions are faster than for the neat system but the thermoplastic seems not to have reacted with the thermoset network. The final blends are transparent but toughening increase is rather low. 相似文献
958.
Michael F. Fink Sophie Schönfeld Constantin Schreck Gerald Hörner Birgit Weber 《Electroanalysis》2023,35(10):e202300154
Electrochemistry and its analytics are essential in a variety of scientific and technological fields where properties related to reduction-oxidation reactions, so-called redox properties, are to be explored. While methodological standards for experiments are well established at room temperature, this is still untrue at sub-zero/cryogenic temperatures, the conditions required for the survey of (ultra−)rapid processes and their intermediates. Problems due to “hand-waving” temperature regulation/conditioning and common usage of pseudo-reference electrodes renders cryo-electrochemistry a great challenge. Herein, we describe a robust setup for performing reliable cryo-electrochemical experiments down to −80 °C. It combines highly stable but flexible temperature conditioning with gas-tight sealing of the electrochemical cell setup. Modification of a commercial palladium hydride reference electrode (PdH RE) allows for rapid temperature cycling under cryogenic conditions in aprotic organic solvents. Validation of the setup with the well-known Ferrocene|Ferrocenium (Fc|Fc+) redox couple gave good compliance with literature data at room temperature in a range of organic solvent-based electrolytes. Evaluation of temperature-dependent diffusion kinetic parameters, such as diffusion coefficients (D) and diffusional activation energies (Ea,D) from CVs at multiple potential scan-rates and temperature levels emphasize the reliability of the presented cryo-electrochemical setup. 相似文献
959.
Dr. You-Jie Yu Dr. Joel Häfliger Dr. Zi-Xuan Wang Dr. Constantin G. Daniliuc Prof. Dr. Ryan Gilmour 《Angewandte Chemie (International ed. in English)》2023,62(38):e202309789
A main-group catalysis-based strategy to access 8-membered carbocycles via the direct carbofunctionalization of 2-phenethyl-substituted 1,3-dienes is disclosed. Through the intervention of an I(I)/I(III) catalysis cycle, the synthesis of densely functionalized, fluorinated benzocyclooctenes can be achieved in an operationally simple manner. Modulating the oxidation/activation regime, and the external nucleophile, the process has been extended to unify the challenging cyclization with formation of allylic C−O, C−N, and C−C bonds (>30 examples). Derivatization of the product benzocyclooctenes is demonstrated together with X-ray conformational analysis, preliminary validation of enantioselective catalysis and a scalable resolution protocol. 相似文献
960.
Dr. You-Jie Yu Dr. Michael Schäfer Dr. Constantin G. Daniliuc Prof. Dr. Ryan Gilmour 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(1):e202214906
A catalysis-based regioselective 1,4-fluorofunctionalization of trifluoromethyl substituted 1,3-dienes has been developed to access compact, highly functionalized products. The process allows E,Z-mixed dienes to be processed to a single E-alkene isomer, and leverages an inexpensive and operationally convenient I(I)/I(III) catalysis platform. The first example of catalytic 1,4-difluorination is disclosed and subsequently evolved to enable 1,4-hetero-difunctionalization, which allows δ-fluoro-alcohol and amine derivatives to be forged in a single operation. The protocol is compatible with a variety of nucleophiles including fluoride, nitriles, carboxylic acids, alcohols and even water thereby allowing highly functionalized products, with a stereocenter bearing both C(sp3)−F and C(sp3)−CF3 groups, to be generated rapidly. Scalability (up to 3 mmol), and facile post-reaction modifications are demonstrated to underscore the utility of the method in expanding organofluorine chemical space. 相似文献