1031246-31-7Relevant articles and documents
Flow reactor approach for the facile and continuous synthesis of efficient Pd@Pt core-shell nanoparticles for acceptorless dehydrogenative synthesis of pyrimidines from alcohols and amidines
Poly, Sharmin Sultana,Hashiguchi, Yuta,Sultana, Asima,Nakamura, Isao,Shimizu, Ken-ichi,Yasumura, Shunsaku,Fujitani, Tadahiro
, (2021/04/23)
Carbon supported Pd@Pt core-shell nanoparticles catalyst was prepared in a flow reactor toachieve enhanced catalytic activities with low Pt loading for the acceptorless dehydrogenative synthesis of pyrimidines. Spectroscopic (XAS analysis) and microscopic (HAADF-STEM) techniques reveled that the core-shell structure was formed by the applied preparation method. The Pd@Pt/PVP (polyvinylpyrrolidone)/C catalyst showed the activity for the three component one pot synthesis of pyrimidines through a series of consecutive reactions including oxidation of alcohols, C[sbnd]C, and C[sbnd]N coupling, followed by heterocyclization and dehydrogenation employing various primary alcohols, secondary alcohols, and amidines. The reaction mechanism on Pd@Pt/PVP/C catalyst was explored by comparison with the control experiments.
Acceptorless Dehydrogenative Synthesis of Pyrimidines from Alcohols and Amidines Catalyzed by Supported Platinum Nanoparticles
Sultana Poly, Sharmin,Siddiki, S. M. A. Hakim,Touchy, Abeda S.,Ting, Kah Wei,Toyao, Takashi,Maeno, Zen,Kanda, Yasuharu,Shimizu, Ken-Ichi
, p. 11330 - 11341 (2019/01/03)
A one-pot, acceptorless dehydrogenative method, using a carbon-supported Pt catalyst (Pt/C) along with KOtBu, has been developed for the synthesis of 2,4,6-trisubstituted pyrimidines from secondary and primary alcohols, and amidines. The reaction takes place efficiently using a wide range of substrate scopes (32 examples with isolated yields up to 92%). The Pt/C catalyst that promotes this process is reusable and has a higher turnover number (TON) than those employed in previously reported methods. The results of mechanistic studies suggest that the process takes place through a pathway that begins with Pt-catalyzed acceptorless dehydrogenation of the alcohol substrate, which is followed by sequential condensation, cyclization, and dehydrogenation. Measurements of the turnover frequency combined with the results of density functional theory calculations on different metal surfaces suggest that the adsorption energy of H on the Pt surface is optimal for the acceptorless dehydrogenation process, which causes the higher catalytic activity of Pt over those of other metals.
Synthetic method of rosuvastatin calcium key intermediate
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, (2016/10/10)
The invention discloses a synthetic method of a rosuvastatin calcium key intermediate. The synthetic method particularly comprises the following steps: carrying out a condensation reaction between fluoroacetophenone and ethyl isobutyrate under the condition of using sodium as alkali by using isopropyl alcohol as a solvent to prepare 1-(4-fluorophenyl)-4-methyl amyl-1,3-diketone; then carrying out a ring closing reaction between the 1-(4-fluorophenyl)-4-methyl amyl-1,3-diketone and methylguanidine hydrochloride by using isopropanol as a solvent to obtain 4-(4-fluorophenyl)-6-isopropyl-N-methyl pyrimidine-2-amine; carrying out a substitution reaction between the 4-(4-fluorophenyl)-6-isopropyl-N-methyl pyrimidine-2-amine and methanesulfonyl chloride by using dichloromethane as a solvent to obtain 4-(4-fluorophenyl)-6-isopropyl-2-[(N-methyl-N-methanesulfonyl) amino] pyrimidine; finally, carrying out a Vilsmeier reaction between the 4-(4-fluorophenyl)-6-isopropyl-2-[(N-methyl-N-methanesulfonyl) amidogen] pyrimidine and DMF (Dimethyl Formamide) as well as phosphoryl chloride to obtain a target compound. The method disclosed by the invention has the advantages of being simple to operate, low in raw material price, high in availability of used raw materials, mild in reaction conditions, low in equipment requirements and production cost, easy for scale production and the like, and has significance industrial application value.
