摘要 通过使用三溴化吡啶鎓作为溴源,通过超声促进和Na 2 CO 3介导的咪唑并[1,2-]区域选择性溴化合成C3-溴化的咪唑并[1,2- a ]吡啶的有效而实用的方案。已经开发了α ]吡啶。该方法有效地避免了使用金属催化剂和苛刻的反应条件,并显示出引人注目的特性,例如操作简便,宽范围的基材范围以及良好至优异的收率,易于规模化生产和高能源效率。
摘要 已开发出铜(I)催化的酮肟肟乙酸酯与简单的吡啶的好氧氧化偶联,用于合成咪唑并[1,2- a ]吡啶。该反应可耐受各种官能团,并且在温和条件下以高收率提供了一系列有价值的咪唑并[1,2- a ]吡啶。 已开发出铜(I)催化的酮肟肟乙酸酯与简单的吡啶的好氧氧化偶联,用于合成咪唑并[1,2- a ]吡啶。该反应可耐受各种官能团,并且在温和条件下以高收率提供了一系列有价值的咪唑并[1,2- a ]吡啶。
A metal-free direct thiolation of imidazoheterocycles with various thiophenol in water at roomtemperature has been developed. In addition, the chemistry provides several advantages including mild condition, high yields, good functional group tolerance, green solvents and suitable for large-scale operations.
Iodine-Mediated Difunctionalization of Imidazopyridines with Sodium Sulfinates: Synthesis of Sulfones and Sulfides
作者:Yu-Jing Guo、Shuai Lu、Lu-Lu Tian、En-Ling Huang、Xin-Qi Hao、Xinju Zhu、Tian Shao、Mao-Ping Song
DOI:10.1021/acs.joc.7b02734
日期:2018.1.5
Novel iodine-induced sulfonylation and sulfenylation of imidazopyridines have been described using sodium sulfinates as the sulfur source. This strategy enables highly selective difunctionalization of imidazo[1,2-a]pyridine to access sulfones and sulfides in good yields. A wide range of substrates and functional groups were well-tolerated under optimized conditions. Moreover, control experiments have
已经描述了使用亚磺酸钠作为硫源的新的碘诱导的咪唑并吡啶的磺酰化和亚磺酰化。该策略能够使咪唑并[1,2- a ]吡啶高度选择性地进行双官能化,从而以高收率获得砜和硫化物。在最佳条件下,各种底物和官能团均具有良好的耐受性。此外,已经进行了对照实验,表明了反应机理中涉及的自由基途径。
Metal-Free Regioselective Alkylation of Imidazo[1,2-a]pyridines with N-Hydroxyphthalimide Esters under Organic Photoredox Catalysis
A visible-light-induced direct C–H alkylation of imidazo[1,2-a]pyridines has been developed. It proceeds at room temperature by employing inexpensive Eosin Y as a photocatalyst and alkyl N-hydroxyphthalimide (NHP) esters as alkylationreagents. A variety of NHP esters derived from aliphatic carboxylicacids (primary, secondary, and tertiary) were tolerated in this protocol, giving the corresponding
amidating reagent has been developed. This protocol is a simple, straightforward, and economic was to afford a variety of N-(2-(imidazo[1,2-a]pyridin-2-yl)phenyl)acetamide derivatives with excellent yields. A mechanistic study reveals that a reversible cleavage of C–H bond might be involved in the reaction.
已经开发了使用二恶唑酮作为酰胺化试剂的Rh(III)催化的2-芳基咪唑杂环的定向邻位酰胺化。该方案简单,直接且经济,目的是以优异的产率提供各种N-(2-(咪唑并[1,2 - a ]吡啶-2-基)苯基)乙酰胺衍生物。一项机理研究表明,该反应可能涉及C–H键的可逆裂解。