Carbon Dioxide → 9-Benzyl-3-(4-trifluoromethoxy-phenyl)-3,9-diaza-bicyclo[3.3.1]nonane-2,4-dione

Participants

Reaction Conditions

Reaction Steps

1,1-Carbonyl diimidazole (CDl; 1.2 g, 7.4 mmol) was added to a mixture of cis-1-benzyl-piperidine-2,6-dicarboxylic acid hydrochloride (1.0 g, 3.34 mmol) and dioxane (10 mL) at rt under N2. The mixture was heated at 100° C. After 15 min, a solution of 4-trifluoromethoxyaniline (600 mg, 3.39 mmol) and dioxane (2 mL) was added. After an additional 2 h, CDl (500 mg, 3.08 mmol) was added (Caution: CO2 evolution). After an additional 1 h, the reaction was allowed to cool to rt, concentrated, diluted with ethyl acetate (120 mL) and washed with 0.5N HCl (100 mL×2). The organic extract was dried, filtered, concentrated, and purified by silica gel chromatography (1:0→4:1; hexanes:ethyl acetate) to give 9-benzyl-3-(4-trifluoromethoxy-phenyl)-3,9-diaza-bicyclo[3.3.1]nonane-2,4-dione: MS (ESI): 405.4 (M+H).

Provenance & Evidence