Synthesis and photophysical insights of new fused N-heterocyclic derivatives with isoquinoline skeleton
作者:Carmen Gherasim、Anton Airinei、Radu Tigoianu、Anda M. Craciun、Ramona Danac、Alina Nicolescu、Dragos Lucian Isac、Ionel I. Mangalagiu
DOI:10.1016/j.molliq.2020.113196
日期:2020.7
Six new fused isoquinoline based compounds (compounds 5a–c with pyrrolo[2,1-a] isoquinoline structure and compounds 6a–c with imidazo[2,1-a]isoquinoline skeleton) have been synthesized using the [3 + 2] cycloaddition of the several in situ generated cycloimmonium ylides to ethyl propiolate or ethyl cyanoformate. All the synthesized compounds have been investigated in solution by UV–VIS absorption,
使用[3 + 2]环加成法合成了六种新的基于异喹啉的稠合化合物(具有吡咯并[2,1- a ]异喹啉结构的化合物5a–c和具有咪唑并[2,1- a ]异喹啉骨架的化合物6a–c)。在几个原位中生成的环亚铵盐生成丙酸乙酯或氰基甲酸乙酯。所有合成的化合物都通过UV-VIS吸收,稳定和时间分辨的荧光方法在溶液中进行了研究。已经证明了取代基对光谱特性的影响。这些衍生物显示出在360至420 nm之间的强烈发射。吡咯并异喹啉衍生物在二甲基亚砜(DMSO)中的发射量子产率(Φ= 0.54-0.64)显着高于咪唑并喹啉(0.03-0.16)。异喹啉衍生物的荧光衰减遵循双指数定律。观察到这些异喹啉衍生物对氢氧化钠的明显反应。
Synthesis of 2-Aminoindolizines by 1,3-Dipolar Cycloaddition of Pyridinium Ylides with Electron-Deficient Ynamides
作者:Julien Brioche、Christophe Meyer、Janine Cossy
DOI:10.1021/acs.orglett.5b01205
日期:2015.6.5
possessing an ynoate or an ynone moiety, have been successfully involved for the first time in a 1,3-dipolarcycloaddition with stabilized pyridiniumylides. These reactions afford an efficient and general access toward a variety of substituted 2-aminoindolizines which can serve as useful precursors for the synthesis of other more complex nitrogen heterocycles.
Construction of C(sp<sup>2</sup>)–X (X = Br, Cl) Bonds through a Copper-Catalyzed Atom-Transfer Radical Process: Application for the 1,4-Difunctionalization of Isoquinolinium Salts
作者:Qiu Sun、Yuan-Yuan Zhang、Jing Sun、Ying Han、Xiaodong Jia、Chao-Guo Yan
DOI:10.1021/acs.orglett.7b03751
日期:2018.2.16
A highly efficient Cu-catalyzed 1,4-difunctionalization of isoquinolinium salts was developed with ether and X– (X = Br, Cl) as the halogen source under mild conditions. This transformation involves the combination of oxidative coupling and copper-catalyzed halogen atom-transfer radicalprocesses. This method not only provides an efficient way to prepare various substituted azaarenes but also achieves
Preparation of 1-trifluoroacetyl indolizines and their derivatives via the cycloaddition of pyridinium N-ylides with 4-4-ethoxy1-1,1,1-trifluorobut-3-en-one
Under basic reaction conditions pyridinium or isoquinolinium N-ylides (C5H5N+ CH2YBr− or C9H7N+CH2YBr−, Y : CO2R, CN, PhCO) reacted readily with 4-ethoxyl-1,1,1-trifluorobut-3-en-2-one to give the corresponding 1-trifluoroacetyl substituted indolizines or pyrrolo-[1,2-a]isoquinolines. The molecular structure of 1-trifluoromethyl-3-methoxyl-pyrrolo-[1,2-a]isoquinoline is presented.
External oxidant-free oxidation/[3+2] cycloaddition/aromatization cascade: electrochemical synthesis of polycyclic N-heterocycles
作者:Qiang Wang、Ting Yuan、Qiang Liu、Yong Xu、Guanqun Xie、Xin Lv、Shujiang Ding、Xiaoxia Wang、Chen Li
DOI:10.1039/c9cc04336e
日期:——
Here, we describe an efficient and environmentally friendly synthesis of polycyclic N-heterocycles under electrochemical external oxidant-free conditions. The extent of the sequential electrochemical oxidativearomatization can be regulated with the assistance of redox mediators.