Potassium Phosphate, Tribasic → Methyl 2-(dimethylphosphoryl)-6-methylisonicotinate

Participants

Reaction Steps

Intermediate I-50b was prepared from Intermediate I-50a following a similar procedure as described in WO2009/143389. A solution of methyl 2-bromo-6-methylisonicotinate (I-50a, 690 mg, 3 mmol) in DMF (12 mL) was treated with dimethylphosphine oxide (515 mg, 6.6 mmol), palladium acetate (39 mg, 0.05 mmol), 4,5-Bis(diphenylphosphino)-9,9-dimethylxanthene (104 mg, 0.18 mmol) and potassium phosphate (700.5 mg, 3.3 mmol). The mixture was purged with nitrogen and subjected to microwave irradiation (20 min, 150° C.). The reaction mixture was concentrated and purified by column chromatography (9:1:0.175N CH2Cl2/MeOH/NH3 in CH2Cl2, 0% to 100%) to afford methyl 2-(dimethylphosphoryl)-6-methylisonicotinate (I-50b) as an off-white solid. 1H NMR (400 MHz, DMSO) ∂ 8.14 (s, 1H), 7.87 (s, 1H), 3.93 (s, 3H), 2.64 (s, 3H), 1.67 (d, J=13.6 Hz, 6H); MS calculated for C10H15NO3P (M+H+) 228.07. found 228.1.

Provenance & Evidence