Efficient, Single-Step Access to Imidazo[1,5-a]pyridine N-Heterocyclic Carbene Precursors
摘要:
The three-component coupling reaction of substituted picolinaldehydes, amines, and formaldehyde to produce imidazo[1,5-a]pyridinium ions is reported, providing an efficient method for the preparation of N-heterocyclic carbenes (NHCs). Reactions proceed in high yields under mild conditions, allowing the incorporation of diverse functionality and chiral substituents. Higher order condensations are also described that provide access to multidentate NHC ligands useful for a variety of applications.
咪唑并[1,5- a ]吡啶碳酸酯与醛和乙炔二甲酸二甲酯或脲基甲酸酯的多组分反应:直接取代完全呋喃的简便方法
摘要:
公开了N,N-取代的咪唑并[1,5- a ]吡啶碳烯的简单的三组分反应,即咪唑并[1,5 - a ]吡啶-3-亚胺与醛和DMAD或脲基甲酸酯的反应。这两个反应都是通过串联亲核加成,[3 + 2]-环加成和环转化进行的,通常以中等收率产生不同的4-[((2-吡啶基)甲基]氨基呋喃衍生物。这项工作不仅提供了咪唑并[1,5 - a ]吡啶-3-吡咯烷在有机合成中的应用的第一个例子,而且还开发了一种直接取代完全呋喃的简单方法,而其他方法不易获得。
The multicomponent reaction of imidazo[1,5-a]pyridine carbenes with phthalaldehydes and dimethyl acetylenedicarboxylate: a facile construction of benzo[d]furo[3,2-b]azepines
phthalaldehydes is reported. The imidazo[1,5-a]pyridine carbenes, namely imidazo[1,5-a]pyridine-3-ylidenes, reacted with phthalaldehydes and DMAD under very mild conditions to producenovel fused tricyclic benzo[d]furo[3,2-b]azepine derivatives. The resulting fused heterocyclic compounds are fluorescent and they give an emission around 500 nm with quantum yields (ΦF) being up to 0.81. This study provides
报道了同时包含N-杂环卡宾和取代的苯二醛的多组分反应的研究。这咪唑并[1,5- a ]吡啶卡宾苯,即咪唑并[1,5 - a ]吡啶-3-吡喃酮,在非常温和的条件下与邻苯二甲醛和DMAD反应生成新的稠合三环苯并[ d ]呋喃[3,2- b ] a庚因衍生物。将所得的稠合杂环化合物是荧光,它们给周围的量子产率(500nm的发射Φ ˚F)至多为0.81。这项研究不仅提供了一种独特的方法来处理稠合的ze庚因衍生物,而这种方法是其他方法不易获得的,而且为复杂的分子骨架开辟了一条新途径。一些产品的长发射波长的荧光特性和高荧光量子产率预示了它们作为光学传感器的潜在应用。
Construction of Novel Tricyclic Fused-Ring Systems by the Multicomponent Reactions of Imidazo[1,5-a]pyridine Carbenes with Aromatic ortho-Dialdehydes and Electron-Deficient Alkynes
作者:Ying Cheng、Cai-Xia Yan、Zhong-Xin Sun
DOI:10.1055/s-0031-1289720
日期:2012.3
The multicomponent reactions of imidazo[1,5-a]pyridine carbenes with heterocyclic ortho-dialdehydes and electron-deficient alkynes were studied. While imidazo[1,5-a]pyridin-3-ylidenes reacted with furan-3,4-dicarbaldehyde and dimethyl acetylenedicarboxylate or dibenzoylacetylene to produce multifunctional difuro[3,2-b:3′,4′-d]azepines, the reaction of imidazo[1,5-a]pyridin-3-ylidenes with thiophene-3
研究了咪唑并[1,5- a ]吡啶碳烯与杂环邻二醛和缺电子炔烃的多组分反应。咪唑并[1,5 - a ]吡啶-3-亚胺与呋喃-3,4-二甲醛和乙炔二羧酸二甲酯或二苯甲酰基乙炔反应生成多功能二呋喃[3,2- b:3',4'- d ]氮杂咪唑并[1,5 - a ]吡啶-3-亚胺与噻吩-3,4-二甲醛和活化炔烃的反应得到呋喃[3,2- b ]噻吩并[3,4- d] a庚因衍生物。这项工作不仅提供了两种新型的三环稠合氮杂环庚烷,而且还扩展了N-杂环卡宾多组分反应在复杂的稠环体系构建中的应用。 多组分反应-卡宾酯-稠环系统-difuro [3,2- b:3',4'- d ] azepines-furo [3,2- b ] thieno [3,4- d ] azepines
Imidazo[1,5-a]pyridine: A Versatile Architecture for Stable N-Heterocyclic Carbenes
作者:Manuel Alcarazo、Stephen J. Roseblade、Andrew R. Cowley、Rosario Fernández、John M. Brown、José M. Lassaletta
DOI:10.1021/ja0423769
日期:2005.3.1
The imidazo[1,5-a]pyridine skeleton provides a versatile platform for the generation of new types of stable N-heterocyclic carbenes. Rh(I) mono- (6) and biscarbenes (7) from imidazo[1,5-a]pyridin-3-ylidenes (ImPy) and derivatives such as 13 from a mesoionic carbene were synthesized and characterized.