2002-24-6Relevant articles and documents
Deep eutectic solvents as attractive media for CO2 capture
Trivedi, Tushar J.,Lee, Ji Hoon,Lee, Hyeon Jeong,Jeong, You Kyeong,Choi, Jang Wook
, p. 2834 - 2842 (2016)
We report a family of deep eutectic solvents (DESs) consisting of various hydrogen bonding donor-acceptor pairs as CO2 capturing media. These DESs capture CO2via carbamate formation upon reaction between their hydrogen bonding donor units and CO2. Among the members tested herein, a DES made up of monoethanolamine hydrochloride-ethylenediamine exhibits an unprecedentedly high gravimetric uptake of 33.7 wt% with good initial kinetics (25.2 wt% uptake within 2.5 min) and recyclability. The given DES also shows sustainable performance in the presence of water, decent tolerance against temperature rise, and a relatively low heat of absorption which is attractive for regeneration. Even with the high gravimetric uptake, the DES has a far more suppressed corrosiveness compared to its pure monoethanolamine and ethylenediamine counterparts due to low oxygen/moisture permeability and the hydrogen bonding network that alleviates the corrosion redox cycle. The observed excellent properties in various key aspects of CO2 capture suggest that DESs are strong candidates to replace the conventional monoethanolamine-based scrubbing technology and are worth further exploration.
Cyclic (Alkyl)(amino)carbene Ligand-Promoted Nitro Deoxygenative Hydroboration with Chromium Catalysis: Scope, Mechanism, and Applications
Zhao, Lixing,Hu, Chenyang,Cong, Xuefeng,Deng, Gongda,Liu, Liu Leo,Luo, Meiming,Zeng, Xiaoming
supporting information, p. 1618 - 1629 (2021/01/25)
Transition metal catalysis that utilizes N-heterocyclic carbenes as noninnocent ligands in promoting transformations has not been well studied. We report here a cyclic (alkyl)(amino)carbene (CAAC) ligand-promoted nitro deoxygenative hydroboration with cost-effective chromium catalysis. Using 1 mol % of CAAC-Cr precatalyst, the addition of HBpin to nitro scaffolds leads to deoxygenation, allowing for the retention of various reducible functionalities and the compatibility of sensitive groups toward hydroboration, thereby providing a mild, chemoselective, and facile strategy to form anilines, as well as heteroaryl and aliphatic amine derivatives, with broad scope and particularly high turnover numbers (up to 1.8 × 106). Mechanistic studies, based on theoretical calculations, indicate that the CAAC ligand plays an important role in promoting polarity reversal of hydride of HBpin; it serves as an H-shuttle to facilitate deoxygenative hydroboration. The preparation of several commercially available pharmaceuticals by means of this strategy highlights its potential application in medicinal chemistry.
Novel synthesis method of Istaroxime
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Paragraph 0107; 0108; 0109; 0110, (2016/10/10)
The invention belongs to the field of pharmaceutical chemistry, and discloses a novel synthesis method of Istaroxime. The method comprises the following steps: by using dehydrogenated epiandrosterone as an initial raw material, carrying out epoxidation, ring opening, reduction, oxidation and other reactions to prepare an intermediate M-06; by using ethyl benzoate as an initial raw material, reacting the ethyl benzoate with hydroxylamine hydrochloride to obtain phenyl hydroximic acid, carrying out hydrochlorination and chlorination by using ethanolamine as a raw material to obtain dichloroacetate, and carrying out substitution, hydrolysis and other reactions on the dichloroacetate and the phenyl hydroximic acid to obtain an intermediate M-11; and finally, reacting the M-06 with the M-11 to obtain the end product Istaroxime. According to the method, in the intermediate M-06 synthesis process, the polarity of all the intermediates has great differences from that of the impurities and reaction reagents; and in the intermediate 11 synthesis process, the active spots capable of participating in the chemical reaction in the reaction substrate are simple. Therefore, the method can achieve the requirements without carrying out column chromatography purification, thereby simplifying the synthesis after-treatment process.
