Palladium-Catalyzed Decarboxylative Cross-Coupling Reactions: A Route for Regioselective Functionalization of Coumarins
作者:Farnaz Jafarpour、Samaneh Zarei、Mina Barzegar Amiri Olia、Nafiseh Jalalimanesh、Soraya Rahiminejadan
DOI:10.1021/jo302778d
日期:2013.4.5
A straightforward, regioselective, and step-economical ligand-free palladium-catalyzed decarboxylative functionalization of coumarin-3-carboxylic acids is devised. This protocol is compatible with a wide variety of electron-donating and -withdrawing substituents and allows for construction of various biologically important π-electron extended coumarins.
in their substituents at the 3-position of the molecular skeleton are demonstrated. The fluorescent quantum yield in solid state increased by up to 92.6% by replacing the α-naphthalene ring (α-NCMs) substituents to β-naphthalene (β-NCMs) ring at the 3-position. Meanwhile, fluorescent colors are successfully tuned by introducing substituents with various electronic properties at the 7-position of the
具有轻微扭曲的分子构象的有机发光体的分子工程学对于固态高效发光是极具挑战性的,但对于发光器件而言是必需的。在该贡献中,证明了两个系列的香豆素衍生物,即α- NCM和β- NCM,它们在分子骨架的3位上的取代基略有不同。通过将α-萘环(α- NCM s)取代基替换为β-萘(β- NCMs)在3位环。同时,通过在分子骨架的7位引入具有各种电子性质的取代基,成功地调节了荧光色。密度泛函理论和单晶分析表明,在3位异构萘环显着影响分子构象,分子堆积模型和分子间相互作用。所有以β - NCM s为磷光体的发光器件比其对应的基于α - NCM s的器件产生更高的发光。在这些设备中,那些具有β -NCM2具有Ñ,Ñ在3.8 V的工作电压下,在7位的-二乙氨基取代基可提供令人印象深刻的54 030 cd / m 2的最大亮度。