Trifluoroacetic Acid in 2,2,2-Trifluoroethanol Facilitates S<sub>N</sub>Ar Reactions of Heterocycles with Arylamines
作者:Benoit Carbain、Christopher R. Coxon、Honorine Lebraud、Kristopher J. Elliott、Christopher J. Matheson、Elisa Meschini、Amy R. Roberts、David M. Turner、Christopher Wong、Celine Cano、Roger J. Griffin、Ian R. Hardcastle、Bernard T. Golding
DOI:10.1002/chem.201304336
日期:2014.2.17
explore diverse sets of reaction conditions, and problems with product purification. In contrast, product isolation from TFA‐TFE reactions is straightforward: evaporation of the reaction mixture, basification and chromatography affords analytically pure material. A total of 45 examples are described with seven discrete heterocyclic scaffolds and 2‐, 3‐ and 4‐substitutedanilines giving product yields
Trifluoroethanol solvent facilitates selective N-7 methylation of purines
作者:Honorine Lebraud、Celine Cano、Benoit Carbain、Ian R. Hardcastle、Ross W. Harrington、Roger J. Griffin、Bernard T. Golding
DOI:10.1039/c3ob27473j
日期:——
Purines protected at N-9 by p-methoxybenzyl are methylated or ethylated in 2,2,2-trifluoroethanol at N-7 by trimethyl- or triethyl-oxonium borofluorate, respectively. Subjecting the resulting cationic species to microwave irradiation releases an N7-methyl- or ethyl-purine. This one-pot procedure is an efficient regiospecific method applicable to diverse substrates.