Copper-Catalyzed Oxyazidation of Unactivated Alkenes: A Facile Synthesis of Isoxazolines Featuring an Azido Substituent
摘要:
A novel and efficient Cu(OAc)(2)-catalyzed oxyazidation of unactivated alkenes was developed. The reactions are easy to conduct, occur under mild conditions, and form azido-substituted isoxazolines in good yields.
A palladium-catalyzed efficient synthesis of 5-methylisoxazoles via oxime-mediated functionalization of unactivatedolefins is described. The reaction affords a variety of 5-methylisoxazoles in moderate to good yields. To further demonstrate the utility of the method, the rapid synthesis of valdecoxib and oxacillin is reported.
A highly efficient copper-catalyzed cyclization/cyanation cascade of unactivated olefins bearing oximes is described. A variety of cyano-containing isoxazolines have been obtained in high yields with cheap Cu(NO3)2·3H2O as the catalyst and TMSCN as the non-metallic cyanide source. The present method provides a mild, simple, and practical access to cyano-substituted isoxazolines and is amenable to gram
Trichloroisocyanuric Acid Promoted Cascade Cyclization/Trifluoromethylation of Allylic Oximes: Synthesis of Trifluoromethylated Isoxazolines
作者:Weigang Zhang、Yingpeng Su、Ke-Hu Wang、Lili Wu、Bingbing Chang、Ya Shi、Danfeng Huang、Yulai Hu
DOI:10.1021/acs.orglett.6b03582
日期:2017.1.20
Cheap and commercially available trichloroisocyanuric acid has been used to promote trifluoromethylation by using TMSCF3 as the trifluoromethyl source. The method provides a novel and efficient protocol for the construction of CF3-containing 4,5-dihydroisoxazoles from allylic oximes in good to excellent yields.
Oxy‐/Amino‐Difluoromethylthiolation of Alkenes: Synthesis of HCF<sub>2</sub>S‐Containing Isoxazolines and Pyrazolines
作者:Xin Chen、Yun‐Tao Shen、Zhi‐Wei Zhao、Yu‐Jian Hou、Bo‐Xun Sun、Tai‐Gang Fan、Ya‐Min Li
DOI:10.1002/adsc.202200672
日期:2022.9.20
Oxy-/amino-difluoromethylthiolation of β,γ-unsaturated oximes/hydrazones have been developed for construction of HCF2S-containing isoxazolines and pyrazolines by employing PhSO2SCF2H as difluoromethylthiolation reagent under mild conditions. Such transformations exhibit good functional group tolerance and scalability. Possible mechanisms are proposed.
β,γ-不饱和肟/腙的氧-/氨基-二氟甲基硫醇化已被开发用于在温和条件下使用PhSO 2 SCF 2 H 作为二氟甲基硫醇化试剂来构建含HCF 2 S 的异恶唑啉和吡唑啉。这种转换表现出良好的官能团耐受性和可扩展性。提出了可能的机制。
Iodine(III)-Mediated Oxy-fluorination of Alkenyl Oximes: An Easy Path to Monofluoromethyl-Substituted Isoxazolines
作者:Weidong Kong、Quanping Guo、Zhaoqing Xu、Guoqiang Wang、Xianxing Jiang、Rui Wang
DOI:10.1021/acs.orglett.5b01646
日期:2015.8.7
A highly regioselective intramolecular oxy-fluorination of alkenyl oximes was achieved. This new transformation represents an efficient method for the preparation of monofluoromethyl-substituted isoxazolines. The synthetic application of the oxy-fluorination product was demonstrated by a one-step synthesis of monofluoromethyl-substituted beta-hydroxyl ketone derivatives.