1,3-acyloxy migration of propargyl α-ketoesters and a carbonyl-ene cyclization of in situ generated allenyl esters. DFT calculations suggest that the copper salt might play dual roles as both chloride abstractor facilitating the generation of highly active gold catalyst and Lewis acid promoting the stepwise intramolecular carbonyl-enereaction.
已经开发了一种双金属协议,以从容易获得的炔丙基 α-酮酯构建 ( Z )-γ-亚烷基丁烯内酯化合物。它涉及金催化的炔丙基α-酮酯的1,3-酰氧基迁移和原位生成的丙二烯酯的羰基-烯环化。DFT 计算表明,铜盐可能起到双重作用,即促进高活性金催化剂生成的氯化物提取剂和促进逐步分子内羰基-烯反应的路易斯酸。
Palladium-catalyzed one-pot synthesis of polysubstituted furans from alkynoates and 2-yn-1-ols
作者:Huawen Huang、Huanfeng Jiang、Hua Cao、Jinwu Zhao、Dabin Shi
DOI:10.1016/j.tet.2011.12.033
日期:2012.4
Easily accessible propargyl vinyl ethers are found to be acyclic precursors to construct furan derivatives. According to the reactive behavior of the substrates and the regulation of reaction conditions, three synthetic routes to polysubstituted furans via palladium-catalyzed reactions of propargyl vinyl ethers in situ-prepared from alkynoates and 2-yn-1-ols are presented herein. These methods could have potential application in synthetic and pharmaceutical chemistry for its facilitation and accessible starting materials. (C) 2011 Elsevier Ltd. All rights reserved.
Asymmetric Synthesis of Chiral Organofluorine Compounds: Use of Nonracemic Fluoroiodoacetic Acid as a Practical Electrophile and Its Application to the Synthesis of Monofluoro Hydroxyethylene Dipeptide Isosteres within a Novel Series of HIV Protease Inhibitors
作者:Andrew G. Myers、Joseph K. Barbay、Boyu Zhong
DOI:10.1021/ja010113y
日期:2001.8.1
(diastereomeric ratios 12:1-84:1), efficient and stereoselectiveroutes to each of the four targeted inhibitors were achieved. The optimized syntheticroute to the most potent inhibitor (syn,syn-4, K(i) = 2.0 nM) proceeded in seven steps (87% average yield per step) from aminoindanol hydrocinnamide 40 and (S)-fluoroiodoacetic acid, and allowed for the preparation of more than 1 g of this compound. The inhibition
描述了一系列 HIV 蛋白酶非对映异构体抑制剂(默克 HIV 蛋白酶抑制剂茚地那韦的单氟化类似物)的两种立体选择性途径。这两条路线的特点是通过不对称烷基化反应立体选择性地构建氟化核心亚基。第一代合成基于来自伪麻黄碱 α-氟乙酰胺的烯醇锂与硝基烯烃 12 的共轭加成,这是一种适度的非对映选择性转化。开发了一种更实用的第二代合成路线,该路线基于一种不对称合成有机氟化合物的新方法,通过使用光学活性氟碘乙酸作为亲电子试剂与手性酰胺烯醇化物相结合进行烯醇化物烷基化。用麻黄碱拆分氟碘乙酸可提供 > 或 = 96% ee 的亲电子试剂的对映体形式。与这种稳定且可储存的手性氟化前体的烷基化反应显示出以高度立体定向的方式进行。随着底物控制的 α-氟酮 44 和 45(非对映体比率 12:1-84:1)的顺式或反选择性还原的发展,实现了四种靶向抑制剂中每一种的有效和立体选择性途径。最有效抑制剂 (syn,syn-4