N-tert-butyl-1-(fluoromethyl)cyclopropane-1-sulfonamide

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a round-bottom flask equipped with a stir bar was added N-(tert-butyl)-1-(fluoromethyl)cyclopropane-1-sulfonamide (5.66 g, 27.0 mmol) and trifluoroacetic acid (20 mL). The solution was stirred at room temperature for 18 h. The solution was concentrated in vacuo to afford a dark orange oil. The oil was treated with hexanes:EtOAc (4:1) upon which a solid crystallized. The crystals were collected via filtrated and residual solvent was removed in vacuo to afford 1-(fluoromethyl)cyclopropane-1-sulfonamide as a colorless, crystalline solid (3.5 g, 84%). 1H NMR (400 MHz, CDCl3) δ 4.79 (s, 1H), 4.67 (s, 1H), 3.28 (br. s., 2H), 1.63-1.56 (m, 2H), 1.16-1.10 (m, 2H). To a round-bottom flask equipped with a stir bar The solution was concentrated in vacuo to afford a dark orange oil crystallized The crystals were collected via filtrated residual solvent was removed in vacuo

反应条件: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a round-bottom flask equipped with a stir bar was added N-(tert-butyl)-1-(hydroxymethyl)cyclopropane-1-sulfonamide (8.66 g, 41.8 mmol) and CH2Cl2 (110 mL). The stirred solution was cooled to 0° C. and to the solution was added (diethylamino)sulfur trifluoride (11 mL, 84 mmol). The solution was allowed to warm to room temperature with stirring for 4 h. The solution was then slowly added to a stirred sat. aq. sodium bicarbonate (100 mL) and following the addition stirring was maintained for 18 h. The pH of the aqueous phase was adjusted to pH=4 using aq. HCl. The mixture was transferred to a separatory funnel and was twice extracted with CH2Cl2. The combined organics were washed with brine; dried over MgSO4; filtered; and then concentrated in vacuo to afford a brown solid residue. This material was subjected to SiO2 chromatography (hexanes:EtOAc, 90:10 to 40:60) to afford N-(tert-butyl)-1-(fluoromethyl)cyclopropane-1-sulfonamide as a colorless, crystalline solid (5.66 g, 65%). 1H NMR (400 MHz, CDCl3) δ 4.73 (s, 1H), 4.60 (s, 1H), 4.22 (br. s., 1H), 1.59-1.53 (m, 2H), 1.37 (s, 9H), 1.12-1.07 (m, 2H). To a round-bottom flask equipped with a stir bar to warm to room temperature the addition stirring was maintained for 18 h The mixture was transferred to a separatory funnel was twice extracted with CH2Cl2 The combined organics were washed with brine dried over MgSO4 filtered and then concentrated in vacuo to afford a brown solid residue