Regio- and Chemoselective Metalation of Chloropyrimidine Derivatives with TMPMgCl center dot LiCl and TMP2Zn center dot 2MgCl(2)center dot 2LiCl

Efficient zincation and magnesiation of chlorinated pyrimidines can be performed at convenient temperatures (e.g., 25 and 55 degrees C) by using TMPMgCl center dot LiCl and TMP2Zn center dot 2MgCl(2)center dot 2LiCl (TMP=2,2,6,6-tetramethylpiperidyl) as effective bases. Quenching of the resulting zincated or magnesiated pyrimidines with various electrophiles furnishes highly functionalized pyrimidines in 51-93% yield. Oxidative aminations were carried out, thus leading to aminated pyrimidines. By using this methodology., we have also prepared pharmaceutically relevant pyrazolopyrimidines and the fungicide Mepanipyrim.