Methyl iodide → 2,4-Dichloro-7-methyl-7H-pyrrolo[2,3-d]pyrimidine

Participants

Reaction Conditions

Reaction Steps

A solution of 2,4-dichloro-7H-pyrrolo[2,3-d]pyrimidine (3.00 g, 16.0 mmol) in anhydrous tetrahydrofuran (45 mL) was cooled to 0° C. and treated with a 60% dispersion of sodium hydride in mineral oil (0.83 g, 20.8 mmol). The reaction was stirred at 0° C. for 20-30 min. The reaction was then treated with iodomethane (3.65 g, 1.6 mL, 25.7 mmol), and the reaction stirred at room temperature overnight. The reaction was diluted with a saturated aqueous ammonium chloride solution (50 mL) and water (50 mL) and was extracted with a 10% methanol in methylene chloride solution (4×50 mL). The combined organic layers were dried over magnesium sulfate, filtered and rinsed with methylene chloride, and concentrated in vacuo onto Celite®. Flash chromatography (80 g silica gel column, 0-15% ethyl acetate/hexanes) afforded 2,4-dichloro-7-methyl-7H-pyrrolo[2,3-d]pyrimidine as a light yellow solid (2.39 g, 74.1%). 1H NMR (400 MHz, DMSO-d6) δ ppm 3.81 (s, 3H) 6.70 (d, J=3.51 Hz, 1H) 7.76 (d, J=3.51 Hz, 1H). LC-MS calcd. for C7H6Cl2N3 [(M+H)+] 202, obsd. 202.0.

Provenance & Evidence