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Kota Miyata Satoru Yasuda Takuto Masuya Satoshi Ito Yusuke Kinoshita Hitoshi Tamiaki Toru Oba 《Tetrahedron》2018,74(27):3707-3711
Iodination of protoporphyrin IX dimethyl ester using phenyliodine bis(trifluoroacetate) (PIFA) and I2 was studied. Iodine added to both the C3- and C8-vinyl groups equally to afford the iodohydrin or iodoether in the presence of water or alcohol, respectively. Any meso-hydrogen atom was not substituted by an iodine atom under these conditions, although both the vinyl group and one of the meso positions of methyl pyropheophorbide-a bearing a chlorin π-system, a chlorophyll-a derivative, was modified with PIFA and I2. The reaction intermediates derived from the porphyrin were more reactive than those from the chlorin and liable to form intermolecular linkages. The obtained 2-iodo-1-hydroxyethyl group was transformed into a formyl group by a mild treatment. The corresponding iodoether moiety was readily converted into the acetyl group under basic conditions. These transformations were also applicable to smaller olefins such as styrene. 相似文献
977.
Pantoyl lactone was selectively oxidized into ketopantoyl lactone with molecular oxygen by the catalysis of ruthenium. 相似文献
978.
Kunichika Nakamiya Yasuyuki Shibata Hiroyasu Ito John S. Edmonds Masatoshi Morita 《应用有机金属化学》2005,19(2):282-286
To facilitate, by the provision of internal standards, the liquid chromatographic and mass spectrometric analysis of diphenylarsinic acid in well water and other samples related to an incident of environmental contamination in Kamisu, Ibaraki, Japan, syntheses of the analogous perdeuterated and mono‐meta‐ and di‐meta‐methylated acids were undertaken. The acids were synthesized by cleavage of the triarylarsines by sodium in liquid ammonia. The triarylarsines were made from the reaction of arsenous chloride and sodium with the appropriate aryl‐bromo compound. Properties of the compounds are given. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
979.
Roberta C. Salles Valdemar Lacerda Jr Adilson Beatriz Felicia M. Ito Reginaldo B. dos Santos Sandro J. Greco Eustáquio V. R. de Castro Dênis P. de Lima 《Magnetic resonance in chemistry : MRC》2010,48(5):409-415
Bioactive cage‐like polycyclic compounds have attracted the attention of several research groups because of their unique appearance and their biological activities. Their structures were established on the basis of 1H NMR and 13C NMR spectroscopic data. The 1H and 13C signal assignments and most homonuclear hydrogen coupling constants were assigned by use of techniques such as 1D 1H and 13C NMR and 2D gCOSY, non‐edited gHSQC and gHMBC. The gNOESY experiments proved the endo‐stereochemistry. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
980.
Cover Picture: Controlled Synthesis of Nanoporous Nickel Oxide with Two‐Dimensional Shapes through Thermal Decomposition of Metal–Cyanide Hybrid Coordination Polymers (Chem. Eur. J. 9/2015)
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