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
Base-Mediated Syntheses of Di- and Trisubstituted Imidazoles from Amidine Hydrochlorides and Bromoacetylenes
作者:Xiao Yun Chen、Ulli Englert、Carsten Bolm
DOI:10.1002/chem.201502707
日期:2015.9.14
A new transition metal‐free method for the preparation of substituted imidazoles from easy‐to‐handle amidinehydrochlorides and bromoacetylenes has been developed. The reactions proceed in air and use inexpensive K2CO3 as base. Additions of 2,2′‐bipyridine and water have beneficial effects on the product yields. Various di‐ and trisubstituted imidazoles have been prepared in good yields (up to 88 %)
已开发出一种新的无过渡金属的方法,该方法由易于处理的am盐酸盐和溴乙炔制备取代的咪唑。反应在空气中进行,并使用廉价的K 2 CO 3作为碱。添加2,2'-联吡啶和水对产品收率有有利影响。各种二,三取代的咪唑均以高收率(高达88%)制备。
Base-Promoted Annulation of Amidoximes with Alkynes: Simple Access to 2,4-Disubstituted Imidazoles
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.
SYNTHESIS OF IMIDAZOLE DERIVATIVES FROM α-HALOOXIMES AND AMIDINES BY USE OF IRON CARBONYLS
作者:Saburo Nakanishi、Junji Nantaku、Yoshio Otsuji
DOI:10.1246/cl.1983.341
日期:1983.3.5
The reaction of α-halooximes with amidines in the presence of iron carbonyls gives imidazole derivatives in good yields. This reaction occurs via deoxygenation of 4H-1,2,5-oxadiazines by iron carbonyls.