A highly stereospecific synthesis of (E)- or (Z)-α-fluoro-α,β-unsaturated ketones 4, via a kinetically controlled Negishi palladium-catalyzed couplingreaction, was developed, providing an easy and general access to valuable fluorinated intermediates (pharmaceutical, peptide mimic, and so on). The synthesis involved a reaction between E/Z gem-bromofluoroolefins 2 and alkoxyvinylzinc species 6 under
Copper-mediated oxidative [3 + 2]-annulation of nitroalkenes and pyridinium ylides: general access to functionalized indolizines and efficient synthesis of 1-fluoroindolizines
作者:Vladimir A. Motornov、Andrey A. Tabolin、Yulia V. Nelyubina、Valentine G. Nenajdenko、Sema L. Ioffe
DOI:10.1039/c8ob03126f
日期:——
+ 2]-annulation of α-fluoronitroalkenes with in situ generated pyridiniumylides was developed. Application of the copper(II) acetate–2,6-lutidine system provides efficient access to various 1-fluoroindolizines in up to 81% yield. Both electron-rich and electron-deficient nitroalkenes as well as different pyridinium and isoquinolinium salts can be involved in the reaction. Moreover, it was found that
Regioselective [3 + 2] cycloaddition of di/trifluoromethylated hydrazonoyl chlorides with fluorinated nitroalkenes: a facile access to 3-di/trifluoroalkyl-5-fluoropyrazoles
作者:Nan Zhang、Hai Ma、Chi Wai Cheung、Fa-Guang Zhang、Marcin Jasiński、Jun-An Ma、Jing Nie
DOI:10.1039/d3ob00644a
日期:——
We describe the base-mediated [3 + 2] cycloaddition reaction of di/trifluoromethylated hydrazonoyl chlorides with fluoronitroalkenes for the synthesis of densely functionalized 3-di/trifluoroalkyl-5-fluoropyrazoles with potent biological activity.
A general method for the synthesis of alpha-fluorocinnamonitrile based on the stereoselective reaction between beta-bromo-beta-fluorostyrene and potassium cyanide, promoted by (CH3CN)(4)Cu+ BF4- in 1-methyl-2-pyrrolidinone (NMP), is described. (C) 2011 Elsevier Ltd. All rights reserved.
Organophotocatalysis Enables the Synthesis of <i>gem</i>-Fluorophosphonate Alkenes