TERT-BUTYL ((3S,4S)-4-AMINOTETRAHYDROFURAN-3-YL)CARBAMATE

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

实验步骤: To a flame-dried round bottom flask under nitrogen containing (3S,4S)-3-aminotetrahydrofuran-4-yl carbamic acid tert-butyl ester (90 mg, 0.45 mmol) and 4-(4-fluorobenzyl)cyclohexanone (87 mg, 0.42 mmol) in 1,2-dichloroethane (6 mL) was added sodium triacetoxyborohydride (191 mg, 0.90 mmol). The resulting yellow mixture was stirred for 15 min and was then poured into 1 N aqueous hydrogen chloride (50 mL). The aqueous layer was basified with 50% aqueous sodium hydroxide and washed with ethyl acetate (4×20 mL). The combined organic layers were dried over sodium sulfate, concentrated, and the resulting residue was purified by flash chromatography (5% methanol in dichloromethane) to yield the desired carbamic acid tert-butyl ester (94 mg, 53%) as a yellow oil. MS (ESI) 393 (M+H). washed with ethyl acetate (4×20 mL) The combined organic layers were dried over sodium sulfate concentrated the resulting residue was purified by flash chromatography (5% methanol in dichloromethane)

反应条件: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A flame-dried round bottom flask under nitrogen was charged with dry tetrahydrofuran (17 mL) and ((3S,4S)-tetrahydro-3,4-furandiamine (170 mg, 1.70 mmol) prepared according to the procedures of Skarzewski, J., et al. Tetrahedron: Asymmetry 1997, 8 (11), 1861. The solution was cooled to −78° C., and 2.5 M n-butyl lithium in hexanes (700 μL, 1.75 mmol) was added. The resulting cloudy white suspension was warmed to 23° C., and the suspension became orange. After 10 min, tert-butyl dicarbonate (371 mg, 1.70 mmol) was added in one portion. An additional 100 mg-portion of tert-butyl dicarbonate was added after 10 min. The reaction was then poured into saturated aqueous sodium chloride (50 mL), and the aqueous layer was washed with ethyl acetate (4×20 mL). The combined organic layers were dried over sodium sulfate, concentrated, and the resulting residue was purified by flash chromatography (5-10% methanol in dichloromethane) to yield the desired amine (90 mg, 26%) as a yellow oil. MS (ESI) 203 (M+H). The resulting cloudy white suspension was warmed to 23° C. the aqueous layer was washed with ethyl acetate (4×20 mL) The combined organic layers were dried over sodium sulfate concentrated the resulting residue was purified by flash chromatography (5-10% methanol in dichloromethane)

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

实验步骤: To a flame-dried round bottom flask under nitrogen containing (3S,4S)-3-aminotetrahydrofuran-4-yl carbamic acid tert-butyl ester (90 mg, 0.45 mmol) and 4-(4-fluorobenzyl)cyclohexanone (87 mg, 0.42 mmol) in 1,2-dichloroethane (6 mL) was added sodium triacetoxyborohydride (191 mg, 0.90 mmol). The resulting yellow mixture was stirred for 15 min and was then poured into 1 N aqueous hydrogen chloride (50 mL). The aqueous layer was basified with 50% aqueous sodium hydroxide and washed with ethyl acetate (4×20 mL). The combined organic layers were dried over sodium sulfate, concentrated, and the resulting residue was purified by flash chromatography (5% methanol in dichloromethane) to yield the desired carbamic acid tert-butyl ester (94 mg, 53%) as a yellow oil. MS (ESI) 393 (M+H). washed with ethyl acetate (4×20 mL) The combined organic layers were dried over sodium sulfate concentrated the resulting residue was purified by flash chromatography (5% methanol in dichloromethane)

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

实验步骤: To a flame-dried round bottom flask under nitrogen containing (3S,4S)-3-aminotetrahydrofuran-4-yl carbamic acid tert-butyl ester (90 mg, 0.45 mmol) and 4-(4-fluorobenzyl)cyclohexanone (87 mg, 0.42 mmol) in 1,2-dichloroethane (6 mL) was added sodium triacetoxyborohydride (191 mg, 0.90 mmol). The resulting yellow mixture was stirred for 15 min and was then poured into 1 N aqueous hydrogen chloride (50 mL). The aqueous layer was basified with 50% aqueous sodium hydroxide and washed with ethyl acetate (4×20 mL). The combined organic layers were dried over sodium sulfate, concentrated, and the resulting residue was purified by flash chromatography (5% methanol in dichloromethane) to yield the desired carbamic acid tert-butyl ester (94 mg, 53%) as a yellow oil. MS (ESI) 393 (M+H). washed with ethyl acetate (4×20 mL) The combined organic layers were dried over sodium sulfate concentrated the resulting residue was purified by flash chromatography (5% methanol in dichloromethane)

反应条件: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A flame-dried round bottom flask under nitrogen was charged with dry tetrahydrofuran (17 mL) and ((3S,4S)-tetrahydro-3,4-furandiamine (170 mg, 1.70 mmol) prepared according to the procedures of Skarzewski, J., et al. Tetrahedron: Asymmetry 1997, 8 (11), 1861. The solution was cooled to −78° C., and 2.5 M n-butyl lithium in hexanes (700 μL, 1.75 mmol) was added. The resulting cloudy white suspension was warmed to 23° C., and the suspension became orange. After 10 min, tert-butyl dicarbonate (371 mg, 1.70 mmol) was added in one portion. An additional 100 mg-portion of tert-butyl dicarbonate was added after 10 min. The reaction was then poured into saturated aqueous sodium chloride (50 mL), and the aqueous layer was washed with ethyl acetate (4×20 mL). The combined organic layers were dried over sodium sulfate, concentrated, and the resulting residue was purified by flash chromatography (5-10% methanol in dichloromethane) to yield the desired amine (90 mg, 26%) as a yellow oil. MS (ESI) 203 (M+H). The resulting cloudy white suspension was warmed to 23° C. the aqueous layer was washed with ethyl acetate (4×20 mL) The combined organic layers were dried over sodium sulfate concentrated the resulting residue was purified by flash chromatography (5-10% methanol in dichloromethane)

反应条件: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A flame-dried round bottom flask under nitrogen was charged with dry tetrahydrofuran (17 mL) and ((3S,4S)-tetrahydro-3,4-furandiamine (170 mg, 1.70 mmol) prepared according to the procedures of Skarzewski, J., et al. Tetrahedron: Asymmetry 1997, 8 (11), 1861. The solution was cooled to −78° C., and 2.5 M n-butyl lithium in hexanes (700 μL, 1.75 mmol) was added. The resulting cloudy white suspension was warmed to 23° C., and the suspension became orange. After 10 min, tert-butyl dicarbonate (371 mg, 1.70 mmol) was added in one portion. An additional 100 mg-portion of tert-butyl dicarbonate was added after 10 min. The reaction was then poured into saturated aqueous sodium chloride (50 mL), and the aqueous layer was washed with ethyl acetate (4×20 mL). The combined organic layers were dried over sodium sulfate, concentrated, and the resulting residue was purified by flash chromatography (5-10% methanol in dichloromethane) to yield the desired amine (90 mg, 26%) as a yellow oil. MS (ESI) 203 (M+H). The resulting cloudy white suspension was warmed to 23° C. the aqueous layer was washed with ethyl acetate (4×20 mL) The combined organic layers were dried over sodium sulfate concentrated the resulting residue was purified by flash chromatography (5-10% methanol in dichloromethane)

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

实验步骤: To a flame-dried round bottom flask under nitrogen containing (3S,4S)-3-aminotetrahydrofuran-4-yl carbamic acid tert-butyl ester (90 mg, 0.45 mmol) and 4-(4-fluorobenzyl)cyclohexanone (87 mg, 0.42 mmol) in 1,2-dichloroethane (6 mL) was added sodium triacetoxyborohydride (191 mg, 0.90 mmol). The resulting yellow mixture was stirred for 15 min and was then poured into 1N aqueous hydrogen chloride (50 mL). The aqueous layer was basified with 50% aqueous sodium hydroxide and washed with ethyl acetate (4×20 mL). The combined organic layers were dried over sodium sulfate, concentrated, and the resulting residue was purified by flash chromatography (5% methanol in dichloromethane) to yield the desired carbamic acid tert-butyl ester (94 mg, 53%) as a yellow oil. MS (ESI) 393 (M+H). washed with ethyl acetate (4×20 mL) The combined organic layers were dried over sodium sulfate concentrated the resulting residue was purified by flash chromatography (5% methanol in dichloromethane)

反应条件: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A flame-dried round bottom flask under nitrogen was charged with dry tetrahydrofuran (17 mL) and ((3S,4S)-tetrahydro-3,4-furandiamine (170 mg, 1.70 mmol) prepared according to the procedures of Skarzewski, J., et al. Tetrahedron: Asymmetry 1997, 8 (11), 1861. The solution was cooled to −78° C., and 2.5 M n-butyl lithium in hexanes (700 μL, 1.75 mmol) was added. The resulting cloudy white suspension was warmed to 23° C., and the suspension became orange. After 10 min, tert-butyl dicarbonate (371 mg, 1.70 mmol) was added in one portion. An additional 100 mg-portion of tert-butyl dicarbonate was added after 10 min. The reaction was then poured into saturated aqueous sodium chloride (50 mL), and the aqueous layer was washed with ethyl acetate (4×20 mL). The combined organic layers were dried over sodium sulfate, concentrated, and the resulting residue was purified by flash chromatography (5–10% methanol in dichloromethane) to yield the desired amine (90 mg, 26%) as a yellow oil. MS (ESI) 203 (M+H). The resulting cloudy white suspension was warmed to 23° C. the aqueous layer was washed with ethyl acetate (4×20 mL) The combined organic layers were dried over sodium sulfate concentrated the resulting residue was purified by flash chromatography (5–10% methanol in dichloromethane)

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

实验步骤: To a flame-dried round bottom flask under nitrogen containing (3S,4S)-3-aminotetrahydrofuran-4-yl carbamic acid tert-butyl ester (90 mg, 0.45 mmol) and 4-(4-fluorobenzyl)cyclohexanone (87 mg, 0.42 mmol) in 1,2-dichloroethane (6 mL) was added sodium triacetoxyborohydride (191 mg, 0.90 mmol). The resulting yellow mixture was stirred for 15 min and was then poured into 1 N aqueous hydrogen chloride (50 mL). The aqueous layer was basified with 50% aqueous sodium hydroxide and washed with ethyl acetate (4×20 mL). The combined organic layers were dried over sodium sulfate, concentrated, and the resulting residue was purified by flash chromatography (5% methanol in dichloromethane) to yield the desired carbamic acid tert-butyl ester (94 mg, 53%) as a yellow oil. MS (ESI) 393 (M+H). washed with ethyl acetate (4×20 mL) The combined organic layers were dried over sodium sulfate concentrated the resulting residue was purified by flash chromatography (5% methanol in dichloromethane)

反应条件: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A flame-dried round bottom flask under nitrogen was charged with dry tetrahydrofuran (17 mL) and ((3S,4S)-tetrahydro-3,4-furandiamine (170 mg, 1.70 mmol) prepared according to the procedures of Skarzewski, J., et al. Tetrahedron: Asymmetry 1997, 8 (11), 1861. The solution was cooled to −78° C., and 2.5 M n-butyl lithium in hexanes (700 μL, 1.75 mmol) was added. The resulting cloudy white suspension was warmed to 23° C., and the suspension became orange. After 10 min, tert-butyl dicarbonate (371 mg, 1.70 mmol) was added in one portion. An additional 100 mg-portion of tert-butyl dicarbonate was added after 10 min. The reaction was then poured into saturated aqueous sodium chloride (50 mL), and the aqueous layer was washed with ethyl acetate (4×20 mL). The combined organic layers were dried over sodium sulfate, concentrated, and the resulting residue was purified by flash chromatography (5-10% methanol in dichloromethane) to yield the desired amine (90 mg, 26%) as a yellow oil. MS (ESI) 203 (M+H). The resulting cloudy white suspension was warmed to 23° C. the aqueous layer was washed with ethyl acetate (4×20 mL) The combined organic layers were dried over sodium sulfate concentrated the resulting residue was purified by flash chromatography (5-10% methanol in dichloromethane)