[H-].[Na+].[C:3]([O:11][CH2:12][CH3:13])(=[O:10])[CH2:4][C:5]([O:7][CH2:8][CH3:9])=[O:6].Br[C:15]1[N:20]=[CH:19][CH:18]=[CH:17][N:16]=1.O>CN(C=O)C>[N:16]1[CH:17]=[CH:18][CH:19]=[N:20][C:15]=1[CH:4]([C:5]([O:7][CH2:8][CH3:9])=[O:6])[C:3]([O:11][CH2:12][CH3:13])=[O:10]To a solution of sodium hydride (4.4 g of a 60% dispersion in oil, 0.11 mol) in DMF (200 ml) was added diethyl malonate (16 ml, 0.11 mol) in DMF (50 ml) dropwise at room temperature. After 30 min 2-bromopyrimidine (8.0 g, 0.05 mol) was added portionwise and the solution heated at 100° C. for 3 h. The solution was cooled to room temperature, water (100 ml) was added and the mixture extracted with EtOAc (3×60 ml). The combined organic layers were dried (MgSO4) and evaporated. The residue was chromatographed on silica, using hexane:EtOAc (3:1) as the eluant, to afford the ester (5.9 g, 49%) as a pale yellow oil which solidified on standing at 0° C. 1H NMR (360 MHz, CDCl3) δ 1.29 (6H, t, J=7.1 Hz), 4.29 (4H, q, J=7.1 Hz), 5.10 (1H, s), 7.26 (1H, t, J=4.9 Hz), 8.74 (2H, d, J=4.9 Hz).
Loading…