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101.
Eiji Tsurumaki Yasuhide Inokuma Shanmugam Easwaramoorthi Dr. Jong Min Lim Dongho Kim Prof. Dr. Atsuhiro Osuka Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(1):237-247
Effective peripheral fabrication methods of meso‐aryl‐substituted subporphyrins were explored for the first time. Hexabrominated subporphyrins 2 were prepared quantitatively from the bromination of subporphyrins 1 with bromine. Hexaphenylated subporphyrins 3 and hexaethynylated subporphyrins 4 and 5 were synthesized by Suzuki–Miyaura coupling and Stille coupling, respectively, in good yields. X‐ray crystal structures of 2 b , 3 b , 4 b , and 5 a revealed preservation of the bowl‐shaped bent structures with bowl depths similar to that of 1 . Hexaethynylated subporphyrins exhibit large two‐photon‐absorption cross‐sections due to effective delocalization of the conjugated network to the ethynyl substituents. 相似文献
102.
Dimethyl ether (DME) was synthesized from methane through a two-step process, in which CH3Br was prepared from the oxidative bromination reaction of methane in the presence of HBr and oxygen over a Rh-SiO2 catalyst and then, in the second step, CH3Br was hydrolyzed to DME over a silica supported metal chloride catalyst. 12 mol%ZnCl2/SiO2 catalyst was found to be the most active, but it deactivated because of Cl− losing. 相似文献
103.
Jinbo Hu 《Journal of fluorine chemistry》2009,(12):1130-1139
Selective incorporation of a fluoroalkyl moiety to modulate the properties of an organic molecule has become a frequently used strategy in life science- and materials science-related applications. In this context, selective introduction of a (phenylsulfonyl)difluoromethyl group (PhSO2CF2) into organic molecules has attracted much attention, since the PhSO2CF2 group can be regarded as a “chemical chameleon” that can be readily transformed into difluoromethyl (CF2H), difluoromethylene (–CF2–), and difluoromethylidene (CF2) functionalities. This article overviews the recent development of (phenylsulfonyl)difluoromethylation reactions from 2003, including the nucleophilic (phenylsulfonyl)difluoromethylations with PhSO2CF2H, PhSO2CF2SiMe3 and PhSO2CF2Br reagents, free radical (phenylsulfonyl)difluoromethylations with PhSO2CF2I reagent, and electrophilic (phenylsulfonyl)difluoromethylations with a hypervalent iodine(III)-CF2SO2Ph reagent. 相似文献
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108.
Addition of bromine to 2-methyl-2-azabicyclo[2.2.1]hept-5-ene was studied. Unexpectedly, 3-bromo-1-methyl-1-azoniatricyclo[2.2.1.02,6]heptane tribromide was isolated rather than the product of bromine addition to the double bond. The former reacted with the starting alkene in a polar solvent to form the corresponding monobromide. 相似文献
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110.
V. T. Abaev M. G. Kadieva A. V. Butin G. D Krapivin E.T. Oganesyan V. E. Zavodnik 《Chemistry of Heterocyclic Compounds》2000,36(11):1261-1271
Methods were developed for the synthesis of 3-butyl-2-(3-oxobutenyl)benzofurans and 3-(3-furylbenzofuran-2-yl)acrylic acids on the basis of 3-furyl-2-(3-oxobutyl)benzofurans. 相似文献