A facile method for direct Pd(OAc)2-catalyzed oxidative cross-coupling of unactivated imidazo[1,2-a]pyridine with simplearenes has been developed. The reaction shows good reaction efficiency, high regioselectivity, and good functional-group compatibility. This approach provides a useful protocol for the preparation of imidazo[1,2-a]pyridine–arene structure of interest in biological and pharmaceutical
已开发了一种简便的方法,用于未活化的咪唑并[1,2- a ]吡啶与简单的芳烃的直接Pd(OAc)2催化的氧化交叉偶联。该反应显示出良好的反应效率,高的区域选择性和良好的官能团相容性。该方法为生物和药物材料中感兴趣的咪唑并[1,2 - a ]吡啶-芳烃结构的制备提供了有用的方案。
N-Heterocyclic carbene–palladium(<scp>ii</scp>)–1-methylimidazole complex catalyzed direct C–H bond arylation of imidazo[1,2-a]pyridines with aryl chlorides
We herein reported the N-heterocyclic carbene–palladium(II)–1-methylimidazole complex catalyzed direct C–H bond arylation of imidazo[1,2-a]pyridines with aryl chlorides. Under suitable conditions, all reactions between various imidazo[1,2-a]pyridines and aryl chlorides worked well to give the desired C3–H arylated products in acceptable to high yields, giving a convenient and alternative method for
我们在本文中报道了N-杂环卡宾-钯(II)-1-甲基咪唑配合物催化的咪唑并[1,2- a ]吡啶与芳基氯化物直接进行CH键芳构化。在合适的条件下,各种咪唑并[1,2- a ]吡啶与芳基氯化物之间的所有反应均能很好地产生所需的C3-H芳基化产物,并且收率高,从而为直接的C-H键提供了一种方便且可替代的方法使用经济且容易获得的芳基氯化物作为芳基化试剂,使咪唑并[1,2- a ]吡啶进行芳基化。
Metal- and base-free synthesis of imidazo[1,2-<i>a</i>]pyridines through elemental sulfur-initiated oxidative annulation of 2-aminopyridines and aldehydes
作者:Jing Tan、Penghui Ni、Huawen Huang、Guo-Jun Deng
DOI:10.1039/c8ob00981c
日期:——
The elemental sulfur-promoted oxidative cyclization reaction for the efficient synthesis of substituted imidazo[1,2-a]pyridines has been developed. Easily available 2-aminopyridines and aldehydes were directly assembled in a highly atom-economical fashion through oxidative annulation under metal- and base-free conditions. Besides arylacetaldehydes, aliphatic aldehydes were also compatible with this
已经开发出用于有效合成取代的咪唑并[1,2- a ]吡啶的元素硫促进的氧化环化反应。容易获得的2-氨基吡啶和醛类在无金属和无碱条件下通过氧化环化法以高度原子经济的方式直接组装。除芳基乙醛外,脂族醛也与该体系相容,以具有克级合成能力的优异收率递送烷基取代的咪唑并[1,2- a ]吡啶。
Facile synthesis of 3-substituted imidazo[1,2-<i>a</i>]pyridines through formimidamide chemistry
作者:Rasapalli Sivappa、Vamshikrishna Reddy Sammeta、Yanchang Huang、James A. Golen、Sergey N. Savinov
DOI:10.1039/c9ra05841a
日期:——
A facile entry to 3-aryl/alkenyl/alkynyl substituted imidazo[1,2-a]pyridines (3a–p, 6a–d & 9a–9e) has been developed from readily available benzyl/allyl/propargyl halides and 2-amino pyridines as substrates via formimidamide chemistry that is devoid of caustic or expensive reagents, such as transition metal complexes. Quantum chemical calculations performed to understand the underlying mechanism of