Modular Synthesis of Di- and Trisubstituted Imidazoles from Ketones and Aldehydes: A Route to Kinase Inhibitors
作者:Ian de Toledo、Thiago A. Grigolo、James M. Bennett、Jonathan M. Elkins、Ronaldo A. Pilli
DOI:10.1021/acs.joc.9b01844
日期:2019.11.1
A one-pot and modular approach to the synthesis of 2,4(5)-disubstituted imidazoles was developed based on ketone oxidation, employing catalytic HBr and DMSO, followed by imidazole condensation with aldehydes. This methodology afforded twenty-nine disubstituted NH-imidazoles (23%-85% yield). A three-step synthesis of 20 kinase inhibitors was achieved by employing this oxidation-condensation protocol
One-Pot Protocol for the Synthesis of Imidazoles and Quinoxalines using<i>N</i>-Bromosuccinimide
作者:Sachin D. Pardeshi、Pratima A. Sathe、Kamlesh S. Vadagaonkar、Atul C. Chaskar
DOI:10.1002/adsc.201700900
日期:2017.12.11
N‐bromosuccinimide (NBS)‐mediated one‐pot, green, efficient and practical synthesis of substituted imidazoles and quinoxalines has been achieved by the reaction of styrenes with N‐arylbenzamidines and o‐phenylenediamines, respectively, in a water:1,4‐dioxane mixture. The reaction involves formation of an α‐bromo ketone as an intermediate in the presence of NBS and water, followed by condensation with
of imidazole ring by a Cs2CO3-promoted annulation of amidoximes with terminal alkynes in DMSO has been developed. This protocol provides a simple synthetic route with high atom-utilization for the synthesis of 2,4-disubstituted imidazoles in good yields under transition-metal-free and ligand-free conditions. Internal alkynes can also undergo the annulation to give 2,4,5-trisubstituted imidazoles.
Hypervalent Iodine in Synthesis 81: A One-Pot Procedure for the Synthesis of 1H-Imidazole Derivatives by Cyclocondensation of Ketones with [Hydroxy(tosyloxy)iodo]benzene and Amidines
作者:Peng-Fei Zhang、Zhen-Chu Chen
DOI:10.1055/s-2001-18059
日期:——
by cyclocondensation of ketones with [hydroxy(tosyloxy)iodo]benzene and selenoamides.6 Herein, we would like to report a one-pot procedure for the synthesis of imidazoles, which includes α-tosyloxylation of ketones with [hydroxy(tosyloxy)iodo]benzene in acetonitrile, followed by treatment with amidines in chloroform. The overall yields of imidazoles are 42–67% without isolation of any intermediates