78573-45-2Relevant articles and documents
Green method for catalyzing deprotection of tetrahydropyrane ether into hydroxyl compound
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Paragraph 0026-0028, (2022/03/17)
The invention provides a green method for catalyzing deprotection of tetrahydropyrane ether into hydroxyl compound, and belongs to the field of green organic chemistry. According to the method, under neutral, open and room-temperature conditions, acetonitrile is used as a reaction solvent, FeBr2 or FeBr3 is used as a catalyst, H2O2 is used as an oxidizing agent, and a tetrahydropyrane ether derivative is converted into a hydroxyl compound within a short time. According to the invention, the catalyst FeBr2 and FeBr3, the oxidizing agent H2O2 and the solvent acetonitrile used in the method are cheap and easy to obtain, the reaction time is short, the condition is mild, the method has wide functional group compatibility, post-treatment is simple, operation is easy, and the method is a current green, environment-friendly and safe method for deprotecting the tetrahydropyrane ether derivative into the hydroxyl compound and has wide application prospects.
Continuous-Flow Amide and Ester Reductions Using Neat Borane Dimethylsulfide Complex
?tv?s, Sándor B.,Kappe, C. Oliver
, p. 1800 - 1807 (2020/02/27)
Reductions of amides and esters are of critical importance in synthetic chemistry, and there are numerous protocols for executing these transformations employing traditional batch conditions. Notably, strategies based on flow chemistry, especially for amide reductions, are much less explored. Herein, a simple process was developed in which neat borane dimethylsulfide complex (BH3?DMS) was used to reduce various esters and amides under continuous-flow conditions. Taking advantage of the solvent-free nature of the commercially available borane reagent, high substrate concentrations were realized, allowing outstanding productivity and a significant reduction in E-factors. In addition, with carefully optimized short residence times, the corresponding alcohols and amines were obtained in high selectivity and high yields. The synthetic utility of the inexpensive and easily implemented flow protocol was further corroborated by multigram-scale syntheses of pharmaceutically relevant products. Owing to its beneficial features, including low solvent and reducing agent consumption, high selectivity, simplicity, and inherent scalability, the present process demonstrates fewer environmental concerns than most typical batch reductions using metal hydrides as reducing agents.
Carbene-Catalyzed α-Carbon Amination of Chloroaldehydes for Enantioselective Access to Dihydroquinoxaline Derivatives
Huang, Ruoyan,Chen, Xingkuan,Mou, Chengli,Luo, Guoyong,Li, Yongjia,Li, Xiangyang,Xue, Wei,Jin, Zhichao,Chi, Yonggui Robin
supporting information, p. 4340 - 4344 (2019/06/14)
An NHC-catalyzed α-carbon amination of chloroaldehydes was developed. Cyclohexadiene-1,2-diimines are used as amination reagents and four-atom synthons. Our reaction affords optically enriched dihydroquinoxalines that are core structures in natural products and synthetic bioactive molecules.