Synthesis of (-)-Oseltamivir by Using a Microreactor in the Curtius Rearrangement
作者:Hayato Ishikawa、Bojan P. Bondzic、Yujiro Hayashi
DOI:10.1002/ejoc.201100074
日期:2011.10
generated isocyanate with a nucleophile was established, which is safe, inexpensive, and suitable for large-scale synthesis. By this flow reaction in the Curtius rearrangement and recrystallization of the late-stage acetamide intermediate the third-generation synthesis of (-)-Oseltamivir has been established, which is efficient, practical, and safe.
A Synthetic Approach to <i>N</i>-Aryl Carbamates via Copper-Catalyzed Chan–Lam Coupling at Room Temperature
作者:Soo-Yeon Moon、U. Bin Kim、Dan-Bi Sung、Won-Suk Kim
DOI:10.1021/jo502828r
日期:2015.2.6
catalyst. The reaction proceeds readily in an open flask at room temperature without additional base, ligand, or additive. Rapid access to urea analogues via a two-step one-pot procedure is enabled by reacting N-arylcarbamates with aluminum–amine complexes. In addition, among several boronic acid derivatives prepared, dimethylphenyl boronate was found to react rapidly in its reaction with benzyl azidoformate
Selective Synthesis of Secondary Arylcarbamates via Efficient and Cost Effective Copper-Catalyzed Mono Arylation of Primary Carbamates with Aryl Halides and Arylboronic Acids
An efficient, selective and cost-effective procedure has been developed for mono N-arylation of primary alkyl and benzyl carbamates with aryliodides and bromides by incorporating CuI as an inexpensive and commercially available catalyst. Despite previous reports on C–N coupling reactions, this process does not need expensive ligands and takes advantage of readily available and inexpensive ethylenediamine
通过引入 CuI 作为廉价且市售的催化剂,已开发出一种高效、选择性和成本效益高的程序,用于伯烷基和苄基氨基甲酸酯与芳基碘化物和溴化物的单 N-芳基化。尽管之前有关于 C-N 偶联反应的报道,但该过程不需要昂贵的配体,并且利用容易获得且价格低廉的乙二胺 (EDA) 作为配体。反应时间相对较短,并且以极好的收率获得了相关的 N-芳基化氨基甲酸酯。有趣的是,用 Cu(OAc)2 代替 CuI 使我们能够使用芳基硼酸作为该反应的偶联伙伴。所有产品均通过 1H- 和 13C-NMR、MS、熔点、IR 和 CHNS 技术进行了充分表征。图形摘要
Reaction of organozinc halides with aryl isocyanates
作者:Haoran Yang、Danfeng Huang、Ke-Hu Wang、Changming Xu、Teng Niu、Yulai Hu
DOI:10.1016/j.tet.2013.01.053
日期:2013.3
Reformatsky reagent, benzylzinc bromide or alkylzinc iodides react with arylisocyanates directly to give corresponding N-substituted carbamates under mild reaction conditions. However, the reaction of allylzinc bromide or propargylzinc bromide with arylisocyanates produces the corresponding N-substituted amides. The reactions provide alternative methods for the synthesis of N-substituted carbamates
Interrupted aza-Wittig reactions using iminophosphoranes to synthesize <sup>11</sup>C–carbonyls
作者:Uzair S. Ismailani、Maxime Munch、Braeden A. Mair、Benjamin H. Rotstein
DOI:10.1039/d1cc01016f
日期:——
A direct CO2-fixation methodology couples structurally diverse iminophosphoranes with various nucleophiles to synthesize ureas, carbamates, thiocarbamates, and amides, and is amenable for 11C radiolabeling. This methodology is practical, as demonstrated by the synthesis of >35 products and isolation of the molecular imaging radiopharmaceuticals [11C]URB694 and [11C]glibenclamide.