We have shown that the BuLi/LiDMAE reagent promotes the clean and regioselective C2 lithiation of 3- and 4-chloropyridines, while other reagents such as LDA or BuLi/TMEDA lead to classical ortho lithiation products or mixtures of regioisomers. The method was successfully applied to the preparation of various reactive 2,3- and 2,4-disubstituted pyridines.
Gribble, Gordon W.; Saulnier, Mark G., Heterocycles, 1993, vol. 35, # 1, p. 151 - 169
作者:Gribble, Gordon W.、Saulnier, Mark G.
DOI:——
日期:——
Etude des ortho-metallations regioselectives de la chloro-3 pyridine par des organolithiens et des amidures de lithium; effet d'orientation par le solvant, applications a la synthese