449-72-9Relevant academic research and scientific papers
Ruthenium?p-cymene complexes with acylthiourea, and its heterogenized form on graphene oxide act as catalysts for the synthesis of quinoxaline derivatives
Bhuvanesh, Nattamai,Gopiraman, Mayakrishnan,Karvembu, Ramasamy,Sindhuja, Dharmalingam,Vasanthakumar, Punitharaj
, (2021/06/30)
Synthesis of a series of half-sandwich Ru(II) complexes (1-5) containing acylthiourea ligand is reported herein. All the Ru(II) complexes were well characterized by analytical and spectroscopic (UV-Vis, FT-IR, NMR and mass spectrometry) methods. Molecular structures of two (2 and 3) of the complexes were confirmed by single crystal X-ray diffraction, and the complexes adopted pseudo-octahedral geometry around Ru. Catalytic ability of the Ru complexes was evaluated in the synthesis of quinoxaline compounds from various 2-nitroaniline and hydroxy ketone derivatives via transfer hydrogenation approach. Active homogeneous catalyst was heterogenized by supporting it on graphene oxide, and the heterogeneous equivalent was characterized by Raman, XPS, TEM, SEM and ICP-OES techniques. Activity of the heterogeneous catalyst was tested, and it can be reused up to five cycles without any loss in activity.
Iron-catalyzed one-pot synthesis of quinoxalines: Transfer hydrogenative condensation of 2-nitroanilines with vicinal diols
Chun, Simin,Hong, Junhwa,Hong, Suckchang,Lee, Seok Beom,Oh, Dong-Chan,Putta, Ramachandra Reddy
, p. 18225 - 18230 (2021/06/03)
Here, we report iron-catalyzed one-pot synthesis of quinoxalines via transfer hydrogenative condensation of 2-nitroanilines with vicinal diols. The tricarbonyl (η4-cyclopentadienone) iron complex, which is well known as the Kn?lker complex, catalyzed the oxidation of alcohols and the reduction of nitroarenes, and the corresponding carbonyl and 1,2-diaminobenzene intermediates were generated in situ. Trimethylamine N-oxide was used to activate the iron complex. Various unsymmetrical and symmetrical vicinal diols were applied for transfer hydrogenation, resulting in quinoxaline derivatives in 49-98% yields. A plausible mechanism was proposed based on a series of control experiments. The major advantages of this protocol are that no external redox reagents or additional base is needed and that water is liberated as the sole byproduct. This journal is
One-pot synthesis of quinoxalines from reductive coupling of 2-nitroanilines and 1,2-diketones using indium
Go, Ahra,Lee, Geunsoo,Kim, Jaeho,Bae, Seolhee,Lee, Byung Min,Kim, Byeong Hyo
, p. 1215 - 1226 (2015/03/04)
The one-pot reduction-cyclization of 2-nitroanilines and 1,2-diketones to give quinoxalines was investigated. Using indium and an appropriate acid such as acetic acid or indium(III) chloride, various quinoxaline derivatives including 2,3-dialkylquinoxalines, 2,3-diphenylquinoxalines, 2,3-di-2-thiophenylquinoxalines, 2,3-di(pyridin-2-yl)quinoxalines, and dibenzo[a,c]phenazines were synthesized in moderate to excellent yield.
