Cesium carbonate → 2-(1-Benzyloxy-ethyl)-7-(3,6-dihydro-2H-pyran-4-yl)-3H-imidazo[5,1-f][1,2,4]triazin-4-one

Participants

Reaction Conditions

Reaction Steps

To a solution of compound 12 (300 mg, 0.75 mmol) in dioxane (2 mL) was added a solution of Cs2CO3 (492 mg, 1.51 mmol) in H2O (0.5 mL) dropwise, followed by addition of 4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-3,6-dihydro-2H-pyran (318 mg, 1.5 mmol) and Pd(PPh3)4 (86 mg, 0.075 mmol). The reaction mixture was degassed by purging with N2 for 15 min. Then the reaction was heated to 125° C. under microwave heating for 40 min. After removal of the solvent, the residue was purified by chromatography on silica gel column (eluted with PE/EtOAc=10:1 to 1:5) to afford compound 13 (200 mg, 75% yield) as white solid. LC-MS: m/z 353 [M+H]+. 1H NMR (400 MHz, CDCl3): δ 8.82 (br. s, 1H), 7.91 (s, 1H), 7.37˜7.32 (m, 5H), 7.19 (br. s, 1H), 4.61 (m, 2H), 4.49 (q, J=6.8 Hz, 1H), 4.40 (m, 2H), 3.95 (t, J=5.2 Hz, 2H), 2.78 (m, 2H), 1.58 (d, J=6.4 Hz, 3H).

Provenance & Evidence