参考标题:Directed Lithiation Of Unprotected Pyridinecarboxylic Acids: Syntheses Of Halo Derivatives 作者:Jalal Lazaar,Anne-Sophie Rebstock,Florence Mongin,Alain Godard,François Trécourt,Francis Marsais,Guy Quéguiner |发布日期:2002.8 摘要:Deprotonation Of All Isomeric Lithium Pyridinecarboxylates And Subsequent Trapping With Hexachloroethane Or Iodine Afforded Straightforward Access To Chloro- And Iodopyridinecarboxylic Acids, Respectively. Starting From Lithium 5-Bromonicotinate, The Introduction Of An Iodine Atom At C4 And Further Halogen Migration Allowed The Potential Of This Method To Be Extended To The Synthesis Of More Elaborate