Synthesis of 5-Substituted Pyrimidines through ortho-Directed Lithiation Reactions

Treatment of 2and/or 4-substituted pyrimidine with LiTMP in ether at O°C, followed by quenching with various electrophiles afforded the corresponding 5-substituted pyrimidines.It is well known that heteroatom-facilitated lithiation of aromatics has been a powerful synthetic tool in organic chemistry due to its high regioselectivity 1.9-1.2(4H, m), 0.95 (3H, t, J=7)1 was obtained v & the addition of g-BuLi to the C=N double bond.