Sodium Carbonate → tert-Butyl 1H-pyrrol-1-ylcarbamate

Participants

Reaction Conditions

Reaction Steps

Under an atmosphere of nitrogen, a solution of 2,5-dimethoxytetrahydrofuran (400 g, 3.03 mol) and tert-butyl carbazate (364 g, 2.75 mol) in 1,4-dioxane (2.5 L) were combined in a flask. Then, aqueous hydrochloric acid solution (2N, 35.8 mL, 71.5 mmol) was added dropwise and the reaction mixture was stirred for 21 hours at 85° C. The reaction mixture was treated with saturated sodium carbonate aqueous solution (120 mL) at room temperature. The quenched mixture was filtered to give a precipitate which was dried to give the title compound as a gray solid (250 g). The organic phase of the filtrate was concentrated and the resultant precipitate was washed with diisopropyl ether (200 mL) and filtered to give the title compound as a gray solid (60 g). The residue was purified by column chromatography on silica gel (hexane:ethyl acetate=4:1→3:1→2:1) to obtain the title compound (47 g). A total of 357 g of the title compound having the following physical data was obtained.

Provenance & Evidence