Cesium carbonate → HCID 68312931, compound

Participants

Reaction Steps

To a suspension of 2-(2-isopropyl-5-methyl-2H-[1,2,4]triazol-3-yl)-4,5-dihydro-6-oxa-1,3a-diazabenzo[e]azulen-8-ol from Example 4 (100 mg, 0.307 mmol) and Cs2CO3 (200 mg, 0.615 mmol) in CH3CN (1 mL) was added a solution of 4-benzyloxy-2-bromo-2-methylbutyric acid benzyl ester (0.345 mmol) in CH3CN (7 mL) and stirring at reflux temperature was continued for 3 h. After cooling to RT, the reaction mixture was partitioned between water and EtOAc. The aqueous phase was extracted with EtOAc and the combined organic layers were washed with water, followed by brine, then dried (Na2SO4) and concentrated in vacuo. The resulting residue was purified by column chromatography (Si-PCC, gradient 2-10% MeOH in DCM) affording 4-Benzyloxy-2-[2-(2-isopropyl-5-methyl-2H-[1,2,4]triazol-3-yl)-4,5-dihydro-6-oxa-1,3a-diazabenzo[e]azulen-8-yloxy]-2-methylbutyric acid benzyl ester as a pale orange gum (36 mg, 19%). LCMS: RT 4.28 min [M+H]+ 622.3

Provenance & Evidence