1,1'-Carbonyldiimidazole → 3-{9-[8-(2,2,2-Trifluoro-acetyl)-8-aza-bicyclo[3.2.1]oct-3-ylidene]-9H-xanthen-3-yl}-4H-[1,2,4]oxadiazol-5-one

Participants

Reaction Conditions

Reaction Steps

To a solution of compound 6a (0.1 g, 0.23 mmol) in 1,4-dioxane (4 mL) was added 1,1′-carbonyldiimidazole (CDl, 0.055 g, 0.34 mmol). The mixture was stirred at 110° C. for 40 min under a nitrogen atmosphere. After being cooled, the reaction was concentrated. The crude compound 6b was used in the next reaction without further purification. MS m/z (MH+) 469.8.

Provenance & Evidence