1,1'-Carbonyldiimidazole → Tert-butyl (1-(3-methyl-1,2,4-oxadiazol-5-yl)cyclopropyl)carbamate

Participants

Reaction Steps

To a solution of N-boc-amino-cyclopropanecarboxylic acid (1.01 g, 5.00 mmol) in 2 mL of DMF was added carbonyldiimidazole (0.812 g, 5.01 mmol). This reaction mixture was stirred at room temperature for 6 h. N-Hydroxy-acetamidine (0.374 g, 5.05 mmol) was added. This reaction mixture was stirred at room temperature for 2 h then heated at 100° C. for 16 h. After cooling to room temperature, the reaction mixture was diluted with water. The resultant precipitate was collected by filtration was washed with acetonitrile and water, air-dried to give [1-(3-methyl-1,2,4-oxadiazol-5-yl)-cyclopropyl]-carbamic acid tert-butyl ester as 1.05 g of white solid, m/z 240 [M+1]+. [1-(3-Methyl-1,2,4-oxadiazol-5-yl)-cyclopropyl]-carbamic acid tert-butyl ester (80 mg, 0.33 mmol) was dissolved in HCl in 1,4-dioxane (4.0 M, 1.0 mL, 4.0 mmol). After standing at room temperature for 1 h, the solvent was removed by a stream of nitrogen. The title compound was isolated and used without further purification.

Provenance & Evidence