Cesium carbonate → (R,Z)-2-amino-7-(2-bromo-4-fluorophenyl)-4-methyl-7,8-dihydropyrido[4,3-d]pyrimidin-5(6H)-one O-2-((S)-2,2-dimethyl-1,3-dioxolan-4-yl)ethyl oxime

Participants

Reaction Steps

To a solution of (R,Z)-2-amino-7-(2-bromo-4-fluorophenyl)-4-methyl-7,8-dihydropyrido[4,3-d]pyrimidin-5(6H)-one oxime (85c, 9.2 mg, 0.025 mmol) in dry DMF (1 mL) was added Cs2CO3 (12.2 mg, 0.0375 mmol) and the reaction mixture stirred at ambient temperature for 30 minutes. Then, (S)-4-(2-iodoethyl)-2,2-dimethyl-1,3-dioxolane (85d, 7.68 mg, 0.03 mmol) was added and the reaction mixture stirred overnight. LCMS showed complete consumption of the starting material. The reaction mixture was poured onto crushed ice and the resulting solid was filtered and rinsed with cold water. Drying afforded (R,Z)-2-amino-7-(2-bromo-4-fluorophenyl)-4-methyl-7,8-dihydropyrido[4,3-d]pyrimidin-5(6H)-one O-2-((S)-2,2-dimethyl-1,3-dioxolan-4-yl)ethyl oxime (7.8 mg, 63%) as a light brown solid. 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 1.35 (s, 3H) 1.41 (s, 3H) 2.02 (qd, J=6.32, 3.03 Hz, 2H) 2.75 (s, 3H) 2.94 (dd, J=16.42, 8.84 Hz, 1H) 3.17 (dd, J=16.42, 4.55 Hz, 1H) 3.59 (dd, J=8.08, 7.07 Hz, 1H) 4.09 (dd, J=8.08, 6.06 Hz, 1H) 4.17-4.28 (m, 3H) 4.98 (ddd, J=8.72, 4.55, 1.64 Hz, 1H) 7.07 (td, J=8.27, 2.65 Hz, 1H) 7.34 (dd, J=8.08, 2.78 Hz, 1H) 7.43 (dd, J=8.72, 5.94 Hz, 1H). MS (ES) [M+H] calculated for C21H27BrFN5O3, 495.11; found 495.30.

Provenance & Evidence