2(1H)-Pyrimidinone, 5-(1-methylethyl)- (9CI) synthesis

Yield:64171-58-0 82%

Reaction Conditions:

with hydrogenchloride in ethanol; for 1 h;Heating / reflux;

Steps:

1

Synthesis of 2-chloro-5-isopropylpyrimidine:; Step 1.; A mixture of 3-ethoxy-2-isopropylprop-2-enal (ref. Menicagli, R. et al. Tetrahedron 1987, 43, 171-177) (250 mg, 1.76 mmol) and urea (250 mg, 4.16 mmol) in ethanol (2.5 mol) was treated with concetrated HCl (0.5 ml) and heated to reflux for 1 hour. Upon cooling, the reaction mixture was neutralized with 1N NaOH (0. 6 mi) and extracted with chtoroform. The organic layer was dried over MgS04 and concentrated to provide 5-isopropylpyrimidin- 2 (1H)-one as an off-white solid (0. 20 g ; 82% yield). 1H NMR (CDCl3) No. 8.15 (s, 2H), 2.72 (sept, 1H, J=6.9), 1.14 (d, 6H, J=6.9).

References:

WO2003/74495,2003,A1 Location in patent:Page/Page column 66