Tunable Electrochemical C−N versus N−N Bond Formation of Nitrogen‐Centered Radicals Enabled by Dehydrogenative Dearomatization: Biological Applications
Herein, an environmentally friendly electrochemical approach is reported that takes advantage of the captodative effect and delocalization effect to generate nitrogen‐centered radicals (NCRs). By changing the reaction parameters of the electrode material and feedstock solubility, dearomatization enabled a selective dehydrogenative C−N versus N−Nbondformation reaction. Hence, pyrido[1,2‐a ]benzimidazole
本文报道了一种环境友好的电化学方法,该方法利用俘获作用和离域作用产生氮中心自由基(NCR)。通过改变电极材料的反应参数和原料溶解度,脱芳香化使选择性脱氢的CN与NN键形成反应成为可能。因此,吡啶[1,2- a ]苯并咪唑和四芳基肼构架是通过具有广泛普遍性的可持续的无过渡金属和外源氧化剂的策略制备的。生物活性测定表明,吡啶并[1,2- a ]苯并咪唑类化合物具有抗微生物活性和对人类癌细胞的细胞毒性。化合物21具有良好的光化学性质,具有大的斯托克斯位移(约130 nm),并成功应用于亚细胞成像。初步的机理研究和密度泛函理论(DFT)计算揭示了可能的反应途径。
Palladium/Silver Synergistic Catalysis in Direct Aerobic Carbonylation of C(sp<sup>2</sup>)<i>−</i>H Bonds Using DMF as a Carbon Source: Synthesis of Pyrido-Fused Quinazolinones and Phenanthridinones
作者:D. Nageswar Rao、Sk. Rasheed、Parthasarathi Das
DOI:10.1021/acs.orglett.6b01292
日期:2016.7.1
An unprecedented Pd/Ag synergistic catalysis in the direct carbonylation of C(sp2)–H bonds utilizing DMF as the carbon source under oxygen is described and demonstrated in the synthesis of pyrido-fused quinazolinone and phenanthridinone scaffolds. Control experiments indicated that the “C” of the carbonyl group is derived from the methyl group of DMF and “O” originates from oxygen as in the case of
Hypervalent iodine(<scp>iii</scp>) catalyzed oxidative C–N bond formation in water: synthesis of benzimidazole-fused heterocycles
作者:D. Nageswar Rao、Sk. Rasheed、Ram A. Vishwakarma、Parthasarathi Das
DOI:10.1039/c4ra02279c
日期:——
A diverse array of benzimidazole-fused heterocycles was synthesized by in situ generated hypervalent iodine(iii) catalyzed intramolecular oxidative C–N bond formation in water and under ambient conditions.
Ir(<scp>iii</scp>)-catalyzed C–H alkynylation of arenes under chelation assistance
作者:Guo-Dong Tang、Cheng-Ling Pan、Fang Xie
DOI:10.1039/c6ob00106h
日期:——
An efficient and mild Ir(III)-catalyzed, chelation assisted C–H alkynylation of arenes has been developed using hypervalent iodine alkynes as alkynylating reagents. A broad scope of N-phenyl-2-aminopyridines and 2-phenoxypyridines has been established as effective substrates for this C–H functionalization and the desired alkynylated products were isolated in moderate to high yields.
Synthesis of<i>N</i>-(2-Pyridyl)indoles via Pd(II)-Catalyzed Oxidative Coupling
作者:Jinlei Chen、Qingyu Pang、Yanbo Sun、Xingwei Li
DOI:10.1021/jo1025546
日期:2011.5.6
Readily available Pd(II) chloride catalysts can catalyze selective and efficientoxidativecoupling between N-aryl-2-aminopyridines and internal alkynes to yield N-(2-pyridyl)indoles. This process involves the ortho C−H activation of N-aryl-2-aminopyridines, and CuCl2 was used as an oxidant. Compared to our previously reported Rh(III)-catalyzed synthesis of this class of product, this method is advantageous