2-芳基苯并恶唑是有前途的分子,可在医学和材料领域得到潜在应用。对2-芳基苯并恶唑的直接区域选择性官能化的有效方案有很高的要求。在本文中,我们公开了通用的Cp * Rh(III)能够以高收率实现2-芳基苯并[ d ]恶唑与烯烃的选择性邻烯化的一般方法。该协议具有广泛的功能基团耐受性和高区域选择性。分子间竞争研究和动力学同位素效应实验表明,氧化烯化过程是通过亲电的C–H活化途径发生的。m的分子结构在间位F原子或杂原子取代基存在的情况下,氟取代的烯化产物可在受阻更强的位置证实区域选择性C–H活化/烯化。在单-和双-烯烃化产物的结构中观察到明显的扭转角,这导致烯烃质子的化学位移明显不同。另外,两个克级反应和进一步的转化实验表明,该方法对于合成邻链烯基化的2-芳基苯并恶唑衍生物是实用的。
Palladium-catalyzed direct arylation of benzoxazoles with unactivated simple arenes
作者:Ge Wu、Jun Zhou、Min Zhang、Peng Hu、Weiping Su
DOI:10.1039/c2cc34238c
日期:——
Using CuBr(2) as an additive, the Pd-catalyzed intermolecular C-H-C-H cross-coupling between benzoxazoles and unactivated simple arenes has been developed. This protocol provides a straightforward approach for the biological activity of 2-arylbenzoxazole derivatives.
An Efficient Synthesis of 2-Substituted Benzoxazoles via RuCl3·3H2O Catalyzed Tandem Reactions in Ionic Liquid
作者:Xuesen Fan、Yan He、Yangyang Wang、Xinying Zhang、Jianji Wang
DOI:10.1002/cjoc.201190156
日期:2011.4
An efficientsynthesis of 2‐substituted benzoxazoles through RuCl3·3H2Ocatalyzed, air oxidized tandemreactions of 2‐aminophenols and aldehydes in [bmim]BF4 was developed. This synthetic strategy has such advantages as mild reaction conditions, cost‐free oxidant, readily available starting materials, and recyclable catalyst and solvent. As an application, it was successfully used in the synthesis of
aerobic oxidative synthesis of 2-arylbenzo[d]oxazoles, 2-substituted benzo[d]thiazoles, and 1,2-disubstituted benzo[d]imidazoles. N-Heterocyclic carbene (NHC), generated in situ from easily available N-heterocyclic imidazolium salt with air as terminal oxidant, has successfully been utilized as a cheap and efficient catalyst for one-pot aerobic oxidative synthesis of 2-arylbenzo[d]oxazoles, 2-substituted
摘要 N-杂环卡宾(NHC)是由易获得的N-杂环咪唑盐以空气为末端氧化剂原位生成的,已成功地用作便宜且有效的一锅好氧氧化合成2-芳基苯并[ d ]恶唑的催化剂,2-取代的苯并[ d ]噻唑和1,2-二取代的苯并[ d ]咪唑。 N-杂环卡宾(NHC)是由易获得的N-杂环咪唑盐以空气为末端氧化剂原位生成的,已成功地用作便宜且有效的一锅好氧氧化合成2-芳基苯并[ d ]恶唑的催化剂,2-取代的苯并[ d ]噻唑和1,2-二取代的苯并[ d ]咪唑。
Synthesis of <i>o</i>-Alkenylated 2-Arylbenzoxazoles via Rh-Catalyzed Oxidative Olefination of 2-Arylbenzoxazoles: Scope Investigation, Structural Features, and Mechanism Studies
protocols for direct regioselective functionalization of 2-arylbenzoxazoles are in high demand. Herein, we disclose a general method for selective ortho-olefination of 2-arylbenzo[d]oxazoles with alkenes enabled by versatile Cp*Rh(III) in high yields. This protocol features broad functional group tolerance and high regioselectivity. Intermolecular competition studies and kinetic isotope effect experiments imply
2-芳基苯并恶唑是有前途的分子,可在医学和材料领域得到潜在应用。对2-芳基苯并恶唑的直接区域选择性官能化的有效方案有很高的要求。在本文中,我们公开了通用的Cp * Rh(III)能够以高收率实现2-芳基苯并[ d ]恶唑与烯烃的选择性邻烯化的一般方法。该协议具有广泛的功能基团耐受性和高区域选择性。分子间竞争研究和动力学同位素效应实验表明,氧化烯化过程是通过亲电的C–H活化途径发生的。m的分子结构在间位F原子或杂原子取代基存在的情况下,氟取代的烯化产物可在受阻更强的位置证实区域选择性C–H活化/烯化。在单-和双-烯烃化产物的结构中观察到明显的扭转角,这导致烯烃质子的化学位移明显不同。另外,两个克级反应和进一步的转化实验表明,该方法对于合成邻链烯基化的2-芳基苯并恶唑衍生物是实用的。