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Johnston, Adam J. S; Ling, Kenneth B; Sale, David; Lebrasseur, Nathalie; Larrosa, Igor
Organic letters, 12/2016, Letnik: 18, Številka: 23Journal Article
Direct arylations of pyridines are challenging transformations due to the high Lewis basicity of the sp2-nitrogen. The use of carboxylates as directing groups is reported, facilitating the Pd-catalyzed C–H arylation of this difficult class of substrates. This methodology allows regioselective C3/C4 arylation, without the need to use solvent quantities of the pyridine, and using low-cost chloro- and bromoarenes as coupling partners. Furthermore, carboxylates could be employed as traceless directing groups through a one-pot C–H arylation/Cu(I)-mediated decarboxylation sequence, thereby accessing directing-group-free pyridine biaryls.
