One-Pot Coupling–Coupling–Cyclocondensation Synthesis of Fluorescent Pyrazoles
作者:Alissa C. Götzinger、Florian A. Theßeling、Corinna Hoppe、Thomas J. J. Müller
DOI:10.1021/acs.joc.6b01326
日期:2016.11.4
ondensation syntheses of pyrazoles and pyrimidines were developed by taking advantage of the provisional, sequentially Pd-catalyzed one-pot generation of alkynones from aryl iodides, ethynylmagnesium bromide, and acid chlorides. This one-pot methodology allows the concise, diversity-oriented generation of a set of donor-, acceptor-, and donor–acceptor-substituted pyrazoles, which are interesting fluorophores
consecutive tandem processes are described for the regioselective, two-step synthesis of 1,3,5-trisubstitutedpyrazoles from α-hydroxyketones. The first, a tandem MnO 2 -mediated oxidation/Ramirez olefination reaction, provides a facile route to β,β-dibromo-enones. These valuable 1,3-dicarbonyl synthons can then be converted into 1,3,5-trisubstitutedpyrazoles via a second tandem hydrazine condensation/Suzuki-Miyaura