18621-17-5Relevant articles and documents
Indirect reduction of CO2and recycling of polymers by manganese-catalyzed transfer hydrogenation of amides, carbamates, urea derivatives, and polyurethanes
Liu, Xin,Werner, Thomas
, p. 10590 - 10597 (2021/08/20)
The reduction of polar bonds, in particular carbonyl groups, is of fundamental importance in organic chemistry and biology. Herein, we report a manganese pincer complex as a versatile catalyst for the transfer hydrogenation of amides, carbamates, urea derivatives, and even polyurethanes leading to the corresponding alcohols, amines, and methanol as products. Since these compound classes can be prepared using CO2as a C1 building block the reported reaction represents an approach to the indirect reduction of CO2. Notably, these are the first examples on the reduction of carbamates and urea derivatives as well as on the C-N bond cleavage in amides by transfer hydrogenation. The general applicability of this methodology is highlighted by the successful reduction of 12 urea derivatives, 26 carbamates and 11 amides. The corresponding amines, alcohols and methanol were obtained in good to excellent yields up to 97%. Furthermore, polyurethanes were successfully converted which represents a viable strategy towards a circular economy. Based on control experiments and the observed intermediates a feasible mechanism is proposed.
Synthesis of Novel Hybrid 4 H -Pyran-lipoic and 4 H -Pyran-azetidine Derivatives
Hernández-Borja, Fernando,Contreras, Leticia,López, Julio,Alcaraz, Yolanda,Cruz, David,Estrada-Soto, Samuel,Delgado, Francisco,Vázquez, Miguel A.
, p. 1020 - 1026 (2017/11/29)
In this study, a molecular hybridization strategy was used to design and synthesize two novel series of hybrid compounds: 4 H -pyran-lipoic and 4 H -pyran-azetidine, employing ammonium hydroxide and involving the participation of aldehydes, malononitrile, and compounds derived from β-ketoesters to obtain the products with good yields.
Preparation method of N-diphenylmethyl-3-hydroxyazetidine
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Paragraph 0022; 0023; 0024; 0025; 0026, (2017/05/16)
The invention relates to a preparation method of azelnidipine intermediate N-(diphenylmethyl)-3-hydroxyazetidine. The preparation method is disclosed based improvement of a conventional method. According to the preparation method, an alkali is added into a reaction system, so that reaction time is shortened from 48h to 16h or less, the reaction time is shortened greatly, and energy consumption is reduced; yield can be maintained to be 83 to 88%, and product purity is increased to be higher than 99.9% via effective adjustment of reaction temperature and appropriate postprocessing, and the preparation method is extremely suitable for industrialized production.