[CH3:1][C:2]1[CH:7]=[C:6]([CH3:8])[N:5]=[C:4]([C:9]#[N:10])[N:3]=1.[CH2:11]([Mg]Br)[CH3:12].B(F)(F)F.CCOCC.O>C1COCC1.CC(O[Ti](OC(C)C)(OC(C)C)OC(C)C)C>[CH3:1][C:2]1[CH:7]=[C:6]([CH3:8])[N:5]=[C:4]([C:9]2([NH2:10])[CH2:12][CH2:11]2)[N:3]=1To a stirred solution of 4,6-dimethylpyrimidine-2-carbonitrile (0.2 g, 1.5 mmol) in anhydrous THF was added Ti(OiPr)4 (0.43 ml, 1.8 mmol, 1.2 eq.). After stirring for 15 min., Ethyl magnesium bromide (3.8 ml, 3.8 mmol, 2.5 eq.) in THF was added dropwise to the mixture at −78° C. (during the addition of EtMgBr the reaction mixture turned black). The reaction mixture was then stirred for an hour at room temperature, and then BF3.Et2O (0.320 ml, 2.2 mmol, 1.5 eq.) was added slowly to the mixture at 0° C. After the addition completed, the reaction was stirred at room temperature for one hour. 50 ml of water was added to the reaction mixture which was then filtered through Celite. The filtrate was basified with 10% NaOH solution (pH=9) and then extracted with DCM (25 ml×2) and washed with brine. The organic layer was concentrated to yield crude product was taken for the next step without purification.
Loading…