4-CHLORO-6-METHYL-6,7-DIHYDRO-5H-CYCLOPENTA[D]PYRIMIDIN-2-AMINE synthesis

Yield:1204408-20-7 34%

Reaction Conditions:

with trichlorophosphate for 3 h;Reflux;

Steps:

4-Chloro-6-methyl-6,7-dihydro-5H-cyclopenta[d]pyrimidin-2-amine (3) Compound 2 (297 mg, 1.8 mmol) and phosphorus oxychloride (15 mL) were heated to reflux for 3 h. The reaction mixture was cooled and evaporated at reduced pressure, and the residue was diluted with chloroform (50 mL) and neutralized with ammonium hydroxide slowly in an ice bath. The organic portion was washed with water (3*30 mL). Solvents were evaporated at reduced pressure, and the residue was purified by column chromatography using chloroform/hexane (4/1) as eluent to afford 112 mg (34%) of 3 as a white-off solid TLC R_f0.48 (CHCl₃/CH₃OH, 10:1); mp: 181.5-182.9° C., ¹H NMR (DMSO-₆): δ 1.16-1.18 (d, 3 H, CH₃), δ 1.55-1.65, 2.15-2.38, 2.49-2.62, 2.83-2.92 (m, 5H, CH₂CHCH₂), δ 6.83 (br, 2H, NH₂, exch). Anal. (C₈H₁₀ClN₃) C, H, N, Cl: calcd, 52.32, 5.49, 22.88, 19.31; found, 52.33, 5.62, 22.63, 19.09.

References:

US2010/10016,2010,A1 Location in patent:Page/Page column 11-12