94-02-0Relevant articles and documents
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Dutt,Rahut
, p. 1725,1726-1731 (1971)
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Shriner,Schmidt,A. G.
, p. 3638 (1929)
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A metal-free strategy for the cross-dehydrogenative coupling of 1,3-dicarbonyl compounds with 2-methoxyethanol
Chang, Yu-Lun,Huang, Sheng-Hua,Kudale, Vishal Suresh,Wang, Jeh-Jeng,Zheng, Sheng
supporting information, p. 1226 - 1230 (2022/02/21)
Here, we report a metal-free approach for the construction of methylene-bridged bis-1,3-dicarbonyl compounds via cross-dehydrogenative coupling of 1,3-dicarbonyl compounds with 2-methoxyethanol. In addition, we have extended this methodology to synthesize tetra-substituted pyridine derivatives using 1,3-dicarbonyl, 2-methoxyethanol and NH4OAc in one step. The key advantages include accepting a wide range of substrates, utilizing O2 as the sole oxidant, and synthesizing biologically active compounds such as 1,4-dihydropyridine and pyrazole. This journal is
Gold N-Heterocyclic Carbene Catalysts for the Hydrofluorination of Alkynes Using Hydrofluoric Acid: Reaction Scope, Mechanistic Studies and the Tracking of Elusive Intermediates
Bédard, Sandrine,Cavallo, Luigi,Falivene, Laura,Gauthier, Rapha?l,Nolan, Steven P.,Paquin, Jean-Fran?ois,Saab, Marina,Tzouras, Nikolaos V.,Van Hecke, Kristof,Zhang, Ziyun
supporting information, (2021/12/09)
An efficient and chemoselective methodology deploying gold-N-heterocyclic carbene (NHC) complexes as catalysts in the hydrofluorination of terminal alkynes using aqueous HF has been developed. Mechanistic studies shed light on an in situ generated catalyst, formed by the reaction of Br?nsted basic gold pre-catalysts with HF in water, which exhibits the highest reactivity and chemoselectivity. The catalytic system has a wide alkyl substituted-substrate scope, and stoichiometric as well as catalytic reactions with tailor-designed gold pre-catalysts enable the identification of various gold species involved along the catalytic cycle. Computational studies aid in understanding the chemoselectivity observed through examination of key mechanistic steps for phosphine- and NHC-coordinated gold species bearing the triflate counterion and the elusive key complex bearing a bifluoride counterion.
Synthetic method of lobeline hydrochloride
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Paragraph 0006; 0027; 0030; 0032; 0034, (2021/06/09)
The invention relates to the technical field of medicine synthesis, and particularly discloses a method for synthesizing lobeline hydrochloride. The method comprises the following steps: performing acylation reaction on ethyl acetoacetate and benzoyl chloride serving as raw materials in the presence of NaOH, NH4Cl and the like, performing hydrolysis reaction on the obtained ethyl benzoylacetate in water in the presence of potassium hydroxide to obtain benzoylacetic acid, carrying out a condensation reaction with glutaraldehyde and methylamine hydrochloride in a citric acid buffer solution, carrying out a reduction reaction on lobeline diketone hydrochloride obtained by the condensation reaction in a mixed solution composed of potassium borohydride, activated carbon, sodium hydroxide and methanol, quenching the reducing agent in the obtained reaction liquid by sulfuric acid, sequentially filtering, extracting, concentrating, cooling and crystallizing to obtain lobeline racemate, then adding L-DBTA, and sequentially performing resolution, dissociation and hydrochlorination to obtain lobeline hydrochloride. The synthesis method has the characteristics of few synthesis steps, simple synthesis conditions, convenience in operation and the like, and the used raw materials have the characteristics of wide source, low price and the like.
