3-fluoropropyl trifluoromethanesulfonate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a cold (−25° C.), stirred solution of 2,6-lutidine (4.60 mL, 39.5 mmol) in DCM (30 mL) was added triflic anhydride (6.00 mL, 35.5 mmol) over 3 min. Then 3-fluoropropane-1-ol (1.61 g, 20.6 mmol) was added. The reaction mixture was warmed to room temperature for 2.5 h. The reaction mixture was then concentrated to half its volume and purified by flash chromatography (Teledyne ISCO CombiFlash, isocratic DCM, REDISEP® SiO2 120 g, detecting at 254 nM, and monitoring at 220 nM). Concentration of the appropriate fractions provided Intermediate S-3A (2.92 g, 67.4%). 1H NMR (400 MHz, chloroform-d) δ ppm 4.69 (2 H, t, J=6.16 Hz), 4.65 (1 H, t, J=5.50 Hz), 4.54 (1 H, t, J=5.61 Hz), 2.25 (1 H, dt, J=11.39, 5.86 Hz), 2.19 (1 H, dt, J=11.44, 5.94 Hz) The reaction mixture was then concentrated to half its volume purified by flash chromatography (Teledyne ISCO CombiFlash, isocratic DCM, REDISEP® SiO2 120 g, detecting at 254 nM, and monitoring at 220 nM) Concentration of the appropriate fractions provided Intermediate S-3A (2.92 g, 67.4%)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of (S)-benzyl 3-(tert-butoxycarbonylamino)pyrrolidine-1-carboxylate (400 mg, 1.2 mmol) and 3-fluoropropyl trifluoromethanesulfonate (433 mg, 2.1 mmol) in tetrahydrofuran (10 mL) was added sodium hydride as 60% dispersion in mineral oil (146 mg, 3.6 mmol). The reaction mixture was stirred at ambient temperature for 30 minutes and then diluted with water (20 mL) and methylene chloride (50 mL). The organic layer was separated, dried over sodium sulfate, filtered, concentrated in vacuo, and purified flash chromatography (silica, 40 g, ISCO, 1-20% methanol in methylene chloride) to afford the title compound as a colorless oil, which was used in the next step without any further purification (475 mg, 100%). The organic layer was separated dried over sodium sulfate filtered concentrated in vacuo purified flash chromatography (silica, 40 g, ISCO, 1-20% methanol in methylene chloride)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of (S)-benzyl 3-(tert-butoxycarbonylamino)pyrrolidine-1-carboxylate (400 mg, 1.2 mmol) and 3-fluoropropyl trifluoromethanesulfonate (433 mg, 2.1 mmol) in tetrahydrofuran (10 mL) was added sodium hydride as 60% dispersion in mineral oil (146 mg, 3.6 mmol). The reaction mixture was stirred at ambient temperature for 30 minutes and then diluted with water (20 mL) and methylene chloride (50 mL). The organic layer was separated, dried over sodium sulfate, filtered, concentrated in vacuo, and purified flash chromatography (silica, 40 g, ISCO, 1-20% methanol in methylene chloride) to afford the title compound as a colorless oil, which was used in the next step without any further purification (475 mg, 100%). The organic layer was separated dried over sodium sulfate filtered concentrated in vacuo purified flash chromatography (silica, 40 g, ISCO, 1-20% methanol in methylene chloride)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a cold (−25° C.), stirred solution of 2,6-Lutidine (4.60 mL, 39.5 mmoL) in DCM (30 mL) was added triflic anhydride (6.00 mL, 35.5 mmoL) over 3 min. Then 3-fluoropropane-1-ol (1.61 g, 20.6 mmoL) was added. The reaction mixture was warmed to room temperature for 2.5 h. The reaction mixture was then concentrated to half its volume and purified by flash chromatography (Teledyne ISCO CombiFlash, isocratic DCM, REDISEP® SiO2 120 g, detecting at 254 nM, and monitoring at 220 nM). Concentration of the appropriate fractions provided Intermediate S-4A (2.92 g, 67.4%). 1H NMR (400 MHz, chloroform-d) δ ppm 4.69 (2H, t, J=6.16 Hz), 4.65 (1H, t, J=5.50 Hz), 4.54 (1H, t, J=5.61 Hz), 2.25 (1H, dt, J=11.39, 5.86 Hz), 2.19 (1H, dt, J=11.44, 5.94 Hz) The reaction mixture was then concentrated to half its volume purified by flash chromatography (Teledyne ISCO CombiFlash, isocratic DCM, REDISEP® SiO2 120 g, detecting at 254 nM, and monitoring at 220 nM) Concentration of the appropriate fractions provided Intermediate S-4A (2.92 g, 67.4%)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a cold (−25° C.), stirred solution of 2,6-lutidine (4.60 mL, 39.5 mmol) in DCM (30 mL) was added triflic anhydride (6.00 mL, 35.5 mmol) over 3 min. Then 3-fluorpropane-1-ol (Oakwood, cat. 010306-25G, 1.61 g, 20.6 mmol) was added. The reaction mixture was warmed to room temperature for 2.5 h. The reaction mixture was concentrated to half its volume and purified by flash chromatography (Teledyne ISCO CombiFlash, isocratic DCM, REDISEP® SiO2 120 g, detecting at 254 nM, and monitoring at 220 nM). Concentration of the appropriate fractions provided Intermediate S-6A (2.92 g, 67.4%). 1H NMR (400 MHz, chloroform-d) δ ppm 4.69 (2H, t, J=6.16 Hz), 4.65 (1H, t, J=5.50 Hz), 4.54 (1H, t, J=5.61 Hz), 2.25 (1H, dt, J=11.39, 5.86 Hz), 2.19 (1H, dt, J=11.44, 5.94 Hz). The reaction mixture was concentrated to half its volume purified by flash chromatography (Teledyne ISCO CombiFlash, isocratic DCM, REDISEP® SiO2 120 g, detecting at 254 nM, and monitoring at 220 nM) Concentration of the appropriate fractions provided Intermediate S-6A (2.92 g, 67.4%)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a cold (−25° C.), stirred solution of 2,6-lutidine (4.60 mL, 39.5 mmol) in DCM (30 mL) was added triflic anhydride (6.00 mL, 35.5 mmol) over 3 min. Then 3-fluoropropane-1-ol (1.61 g, 20.6 mmol) was added. The reaction mixture was warmed to room temperature for 2.5 h. The reaction mixture was then concentrated to half its volume and purified by flash chromatography (Teledyne ISCO CombiFlash, isocratic DCM, REDISEP® SiO2 120 g, detecting at 254 nM, and monitoring at 220 nM). Concentration of the appropriate fractions provided Intermediate S-3A (2.92 g, 67.4%). 1H NMR (400 MHz, chloroform-d) δ ppm 4.69 (2 H, t, J=6.16 Hz), 4.65 (1 H, t, J=5.50 Hz), 4.54 (1 H, t, J=5.61 Hz), 2.25 (1 H, dt, J=11.39, 5.86 Hz), 2.19 (1 H, dt, J=11.44, 5.94 Hz) The reaction mixture was then concentrated to half its volume purified by flash chromatography (Teledyne ISCO CombiFlash, isocratic DCM, REDISEP® SiO2 120 g, detecting at 254 nM, and monitoring at 220 nM) Concentration of the appropriate fractions provided Intermediate S-3A (2.92 g, 67.4%)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of (S)-benzyl 3-(tert-butoxycarbonylamino)pyrrolidine-1-carboxylate (400 mg, 1.2 mmol) and 3-fluoropropyl trifluoromethanesulfonate (433 mg, 2.1 mmol) in tetrahydrofuran (10 mL) was added sodium hydride as 60% dispersion in mineral oil (146 mg, 3.6 mmol). The reaction mixture was stirred at ambient temperature for 30 minutes and then diluted with water (20 mL) and methylene chloride (50 mL). The organic layer was separated, dried over sodium sulfate, filtered, concentrated in vacuo, and purified flash chromatography (silica, 40 g, ISCO, 1-20% methanol in methylene chloride) to afford the title compound as a colorless oil, which was used in the next step without any further purification (475 mg, 100%). The organic layer was separated dried over sodium sulfate filtered concentrated in vacuo purified flash chromatography (silica, 40 g, ISCO, 1-20% methanol in methylene chloride)