65182-57-2Relevant academic research and scientific papers
Hydrogen-Transfer-Mediated α-Functionalization of 1,8-Naphthyridines by a Strategy Overcoming the Over-Hydrogenation Barrier
Chen, Xiu-Wen,Zhao, He,Chen, Chun-Lian,Jiang, Huan-Feng,Zhang, Min
, p. 14232 - 14236 (2017)
A general catalytic hydrogen transfer-mediated α-functionalization of 1,8-naphthyridines is reported for the first time that benefits from a hydrogen transfer-mediated activation mode for non-activated pyridyl cores. The pyridyl α-site selectively couples with the C8-site of various tetrahydroquinolines (THQs) to afford novel α-functionalized tetrahydro 1,8-naphthyridines, a class of synthetically useful building blocks and potential candidates for the discovery of therapeutic and bio-active products. The utilization of THQs as inactive hydrogen donors (HDs) appears to be a key strategy to overcome the over-hydrogenation barrier and address the chemoselectivity issue. The developed chemistry features operational simplicity, readily available catalyst and good functional group tolerance, and offers a significant basis for further development of new protocols to directly transform or functionalize inert N-heterocycles.
Catalytic activity in transfer hydrogenation using ruthenium (II) carbonyl complexes containing two 1,8-naphthyridine as N-monodentate ligands
Gajardo, Juana,Araya, Juan C.,Ibá?ez, Andrés,Guerchais, Véronique,Le Bozec, Hubert,Moya, Sergio A.,Aguirre, Pedro
supporting information, p. 129 - 134 (2018/11/03)
A new series of novel complexes of type cis-[Ru(CO)2Cl2(L)2], L = 2-phenyl-1,8-naphthyridine, 2-(4′-nitrophenyl)-1,8-naphthyridine, 2-(4′-bromophenyl)-1,8-naphthyridine, 2-(4′-methylphenyl)-1,8-naphthyridine, 2-(3′-methoxyphenyl)-1,8-naphthyridine, 2-(2′-methoxyphenyl)-1,8-naphthyridine and 2-(4′-methoxyphenyl)-1,8-naphthyridine have been successfully synthesized and characterized. We found that the complexes can be directly synthesized from [RuCl2(CO)2]2 with high yield. The crystallographic structures of complex cis-[RuCl2(CO)2(2-(4′-methoxyphenyl)-1,8-naphthyridine-κN8)2] and cis-[RuCl2(CO)2(2-(2′-methoxyphenyl)-1,8-naphthyridine-κN8)2] have been established by X-ray single crystal diffraction studies, which indicate an octahedral geometry with two 1,8-naphthyridine ligands coordinated to the metal in a N-monodentate fashion. The ruthenium(II) complexes have been studied as catalysts in the transfer hydrogenation of acetophenone. We found that complexes show moderate activities and a 100% selectivity. The best turnover frequency (390 h?1) is found for cis-[RuCl2(CO)2(2-(4′-methoxyphenyl)-1,8-naphthyridine-κN8)2] when the substrate/catalysis ratio was 1000/1. The catalytic conditions were optimized using different substrate/catalyst and base/catalyst ratios.
Transition metal-free α-methylation of 1,8-naphthyridine derivatives using DMSO as methylation reagent
Jiang, Shaohua,Yang, Zhihai,Guo, Ziyin,Li, Yibiao,Chen, Lu,Zhu, Zhongzhi,Chen, Xiuwen
, p. 7416 - 7424 (2019/08/15)
A practical approach to the direct α-methylation of 1,8-naphthyridines under mild reaction conditions has been developed using simple and readily available DMSO as a convenient and environmentally friendly carbon source. This method is transition metal-free and highly chemoselective, shows good functional group tolerance, and uses DMSO as a methyl source, providing efficient and rapid access to an important compound class, 2-methyl-1,8-naphthyridines.
Direct Access to Nitrogen Bi-heteroarenes via Iridium-Catalyzed Hydrogen-Evolution Cross-Coupling Reaction
Chen, Chunlian,Chen, Xiuwen,Zhao, He,Jiang, Huanfeng,Zhang, Min
supporting information, p. 3390 - 3393 (2017/07/15)
Through cooperative actions of iridium catalyst and NaOTf additive we report a new direct access to nitrogen bi-heteroarenes via hydrogen-evolution cross-coupling of the β-site of indoles/pyrrole with the α-site of N-heteroarenes. The reaction proceeds in an atom- and redox-economic fashion together with the merits of an easily available catalyst system, broad substrate scope, excellent functional tolerance, and no need for external oxidants, offering a practical way to create π-conjugated systems.
Microwave assisted synthesis of 1,8- naphthyridines
Mogilaiah,Reddy,Rao
, p. 837 - 838 (2007/10/03)
A highly efficient and practical methodology for the synthesis of 2-aryl-1.8-naphthyridines 3 is described starting from 2-aminonicotinaldehyde 1 and various acetophenones under microwave conditions.
Substituted 1,8-Naphthyridines: Part VI - Synthesis of 3-Aroyl-2-phenyl-1,8-naphthyridines
Rao, G. Rama,Mogilaiah, K.,Reddy, K. Rajendar,Sreenivasulu, B.
, p. 200 - 202 (2007/10/02)
The condensation of 2-aminonicotinaldehyde (1) with ω-benzoylacetophenones (2) leads to either 3-aroyl-2-phenyl-1,8-naphthyridines (3) in the presence of gl. acetic acid containing a catalytic amount of conc.H2SO4, or to 2-aryl-1,8-naphthyridines (4) in e
