(2S)-oxolane-2-carbonyl chloride

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a 250-mL three neck round-bottom flask, which was purged and maintained with an inert atmosphere of nitrogen, was added a solution of (diazomethyl)trimethylsilane (20 mL, 2 M in hexane) in ether (150 mL). A solution of (S)-tetrahydrofuran-2-carbonyl chloride (compound 257.1, 5.00 g, 37.2 mmol, 1.00 equiv) in ether/DCM (25/10 mL) was added dropwise at 0° C. and stirred for 20 min at 0° C. Hydrogen bromide (48%) (8 mL, 1.50 equiv) was added dropwise. The resulting solution was stiffed for 30 min at 10° C., then washed with 2×100 mL of water and 1×50 mL of brine. The mixture was dried over anhydrous sodium sulfate and concentrated in vacuo. The residue was purified using silica gel column chromatography with ethyl acetate/petroleum ether (1:50) as eluent to furnish 2.50 g (35%) of (S)-2-bromo-1-(tetrahydrofuran-2-yl)ethanone as a yellow oil. To a 250-mL three neck round-bottom flask, which was purged maintained with an inert atmosphere of nitrogen was added a solution of (diazomethyl)trimethylsilane (20 mL, 2 M in hexane) in ether (150 mL) The resulting solution was stiffed for 30 min at 10° C. washed with 2×100 mL of water and 1×50 mL of brine The mixture was dried over anhydrous sodium sulfate concentrated in vacuo The residue was purified

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a 250-mL three neck round-bottom flask, which was purged and maintained with an inert atmosphere of nitrogen, was added a solution of (diazomethyl)trimethylsilane (20 mL, 2 M in hexane) in ether (150 mL). A solution of (S)-tetrahydrofuran-2-carbonyl chloride (compound 257.1, 5.00 g, 37.2 mmol, 1.00 equiv) in ether/DCM (25/10 mL) was added dropwise at 0° C. and stirred for 20 min at 0° C. Hydrogen bromide (48%) (8 mL, 1.50 equiv) was added dropwise. The resulting solution was stiffed for 30 min at 10° C., then washed with 2×100 mL of water and 1×50 mL of brine. The mixture was dried over anhydrous sodium sulfate and concentrated in vacuo. The residue was purified using silica gel column chromatography with ethyl acetate/petroleum ether (1:50) as eluent to furnish 2.50 g (35%) of (S)-2-bromo-1-(tetrahydrofuran-2-yl)ethanone as a yellow oil. To a 250-mL three neck round-bottom flask, which was purged maintained with an inert atmosphere of nitrogen was added a solution of (diazomethyl)trimethylsilane (20 mL, 2 M in hexane) in ether (150 mL) The resulting solution was stiffed for 30 min at 10° C. washed with 2×100 mL of water and 1×50 mL of brine The mixture was dried over anhydrous sodium sulfate concentrated in vacuo The residue was purified

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 21.8 g (32.0 mmol) imidazole are placed in 400 ml chloroform and cooled to 0° C. 21.5 g (15.0 mmol) (S)-tetrahydrofuran-2-carbonyl chloride are added dropwise, then stirred for 1.5 hours at ambient temperature. After cooling again to 0° C. the reaction mixture is extracted with semisaturated sodium chloride solution. The organic phase is dried and evaporated to dryness. Yield: 23.5 g After cooling again to 0° C. the reaction mixture is extracted with semisaturated sodium chloride solution The organic phase is dried evaporated to dryness

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a 250-mL three neck round-bottom flask, which was purged and maintained with an inert atmosphere of nitrogen, was added a solution of (diazomethyl)trimethylsilane (20 mL, 2 M in hexane) in ether (150 mL). A solution of (S)-tetrahydrofuran-2-carbonyl chloride (compound 257.1, 5.00 g, 37.2 mmol, 1.00 equiv) in ether/DCM (25/10 mL) was added dropwise at 0° C. and stirred for 20 min at 0° C. Hydrogen bromide (48%) (8 mL, 1.50 equiv) was added dropwise. The resulting solution was stiffed for 30 min at 10° C., then washed with 2×100 mL of water and 1×50 mL of brine. The mixture was dried over anhydrous sodium sulfate and concentrated in vacuo. The residue was purified using silica gel column chromatography with ethyl acetate/petroleum ether (1:50) as eluent to furnish 2.50 g (35%) of (S)-2-bromo-1-(tetrahydrofuran-2-yl)ethanone as a yellow oil. To a 250-mL three neck round-bottom flask, which was purged maintained with an inert atmosphere of nitrogen was added a solution of (diazomethyl)trimethylsilane (20 mL, 2 M in hexane) in ether (150 mL) The resulting solution was stiffed for 30 min at 10° C. washed with 2×100 mL of water and 1×50 mL of brine The mixture was dried over anhydrous sodium sulfate concentrated in vacuo The residue was purified