Efficient zincation and magnesiation of chlorinated pyrimidines can be performed at convenient temperatures (e.g., 25 and 55 degrees C) by using TMPMgCl x LiCl and TMP(2)Zn x 2 MgCl(2) x 2 LiCl (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.
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