17024-55-4Relevant academic research and scientific papers
Room-Temperature Amination of Chloroheteroarenes in Water by a Recyclable Copper(II)-Phosphaadamantanium Sulfonate System
Dandela, Rambabu,Desai, Aman A.,Kapdi, Anant R.,Kori, Santosh,Maity, Dilip K.,Parmar, Udaysinh,Somvanshi, Dipesh
, p. 8900 - 8925 (2021/07/20)
Buchwald-Hartwig amination of chloroheteroarenes has been a challenging synthetic process, with very few protocols promoting this important transformation at ambient temperature. The current report discusses about an efficient copper-based catalytic system (Cu/PTABS) for the amination of chloroheteroarenes at ambient temperature in water as the sole reaction solvent, a combination that is first to be reported. A wide variety of chloroheteroarenes could be coupled efficiently with primary and secondary amines as well as selected amino acid esters under mild reaction conditions. Catalytic efficiency of the developed protocol also promotes late-stage functionalization of active pharmaceutical ingredients (APIs) such as antibiotics (floxacins) and anticancer drugs. The catalytic system also performs efficiently at a very low concentration of 0.0001 mol % (TON = 980,000) and can be recycled 12 times without any appreciable loss in activity. Theoretical calculations reveal that the π-acceptor ability of the ligand PTABS is the main reason for the appreciably high reactivity of the catalytic system. Preliminary characterization of the catalytic species in the reaction was carried out using UV-VIS and ESR spectroscopy, providing evidence for the Cu(II) oxidation state.
Regioselective nitro group substitution. synthesis of isomeric 4-amino-5-nitro- and 5-amino-4-nitroimidazoles
Zaprutko, Lucjusz,Zwawiak, Justyna,Olender, Dorota,Gzella, Andrzej
, p. 2197 - 2211,15 (2020/08/31)
On the basis of the reactions between 4,5-dinitroimidazole derivatives (1-methyl-4,5-dinitroimidazole, 1,2-dimethyl-4,5-dinitroimidazole and ethyl 2- (4,5-dinitroimidazol-1-yl)acetate) and cyclic amines (morpholine, piperidine or pyrrolidine) in mild cond
Nucleophilic Displacements of Imidazoles.I. Oxygen,Nitrogen and Carbon Nucleophiles
Kulkarni, Surendra,Grimmett, M. Ross,Hanton, Lyall R.,Simpson, Jim
, p. 1399 - 1413 (2007/10/02)
4(5)-Bromo- and -iodo-imidazoles, activated by an adjacent nitro substituent, undergo nucleophilic displacement with methoxide, phenoxide, cyclic secondary amines and cyanide.The regiochemistry of the reactions of 5-iodo-4-nitroimidazole with methoxide has been confirmed by spectroscopic and X-ray methods, and a number of erroneous structures from the literature have been revised.Some apparently anomalous reactions of methoxide with 5-halo-1,2-dimethyl-4-nitroimidazoles, and of cyanide with 4-halo-1-methyl-5-nitroimidazole have been noted.The crystal and molecular structure of 5-methoxy-1-methyl-4-nitroimidazole has been determined by direct methods.Crystals are monoclinic, P21/c, a 10.929(3), b 8.899(2), c 7.290(2) Angstroem; β 92.87(2) deg; Z 4.The structure was refined to R=0.095 for 818 reflections (I.2?I).
