(R)-4-((R)-1-(叔丁氧基)乙基)噁唑烷-2-酮

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

实验步骤: To a solution of (R)-4-((R)-1-(tert-butoxy)ethyl)oxazolidin-2-one (6.35 g, 33.9 mmol) in DMF (170 mL) under a nitrogen atmosphere at 0° C. was added sodium hydride (2.14 g, 50.9 mmol, 60%) portion wise over 3 minutes. The reaction mixture was then stirred for 2 hr at 0° C. whereupon 2,4,5-Trifluoropyrimidine (5 g, 37.3 mmol) was added and the reaction mixture allowed to stir 75 minutes at 0° C. then the mixture was allowed to warm to RT and stirred for 1 hr at RT. The reaction mixture was quenched with the slow addition of saturated solution of NH4Cl and the aqueous mixture extracted with EtOAc. Organic phases combined, washed with water, brine, dried (Na2SO4), filtered and concentrated onto silica gel. Silica gel column chromatography (EtOAc/Heptane 0 to 50%) provided a colorless oil of (R)-4-((R)-1-(tert-butoxy)ethyl)-3-(2,5-difluoropyrimidin-4-yl)oxazolidin-2-one (6.97 g, 23.1 mmol, 68% yield) which crystallizes upon standing. 1H NMR (400 MHz, CDCl3) 1.10 (d, J=6.26 Hz, 3H) 1.18 (s, 9H) 4.25-4.35 (m, 1H) 4.49-4.62 (m, 2H) 4.65-4.73 (m, 1H) 8.45 (d, J=1.57 Hz, 1H). LCMS m/z 246.1 (-t-butyl fragment) (M+H)+, Rt 0.91 min. was added to warm to RT stirred for 1 hr at RT The reaction mixture was quenched with the slow addition of saturated solution of NH4Cl the aqueous mixture extracted with EtOAc washed with water, brine dried (Na2SO4) filtered concentrated onto silica gel

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

实验步骤: Sodium hydride (60% dispersion in mineral oil, 23 mg, 0.58 mmol, 1.2 equiv) was added to a solution of methyl 2,6-dichloropyrimidine-4-carboxylate (100 mg, 0.483 mmol) and (R)-4-((R)-1-(tert-butoxy)ethyl)oxazolidin-2-one (90 mg, 0.483 mmol, 1 equiv) in DMF (2.4 mL) at 0° C. The suspension was stirred at 0° C. for 1 hour, by which time it turned yellow. The reaction was quenched with dilute aqueous sodium chloride (20 mL) and extracted with ethyl acetate (2×20 mL). The combined extracts were dried over Na2SO4, filtered and concentrated. Silica gel column chromatography (EtOAc/Heptane) separated the regioisomers and provided methyl 6-((R)-4-((R)-1-(tert-butoxy)ethyl)-2-oxooxazolidin-3-yl)-2-chloropyrimidine-4-carboxylate (0.111 g, white solid) in 64% yield. 1H NMR (400 MHz, CDCl3) δ 8.79 (s, 1H), 4.76 (m, 1H), 4.69 (dd, J=9.4, 2.7 Hz, 1H), 4.52-4.41 (m, 2H), 4.02 (s, 3H), 1.26 (s, 9H), 1.05 (d, J=6.6 Hz, 3H). MS m/z 358.2 (M+H)+; Rt-1.00 min. The reaction was quenched with dilute aqueous sodium chloride (20 mL) extracted with ethyl acetate (2×20 mL) The combined extracts were dried over Na2SO4 filtered concentrated Silica gel column chromatography (EtOAc/Heptane) separated the regioisomers

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

实验步骤: A solution of (R)-4-((R)-1-tert-butoxyethyl)oxazolidin-2-one (0.100 g, 0.534 mmol) and 4-chloro-6-(difluoromethyl)-2-(methylthio)pyrimidine (0.124 g, 0.587 mmol, 1.10 equiv) in DMF (2.7 mL) was treated with NaH (60%, 0.026 g, 0.64 mmol, 1.20 equiv), then the resulting mixture (yellow) was stirred at room temperature for 30 min. The reaction mixture was diluted with EtOAc (20 mL), washed with saturated aqueous NaCl (2×20 mL), dried over Na2SO4, filtered and concentrated. Silica gel column chromatography (EtOAc/Heptane 0 to 40%) provided (R)-4-((R)-1-tert-butoxyethyl)-3-(6-(difluoromethyl)-2-(methylthio)pyrimidin-4-yl)oxazolidin-2-one (0.164 g, white solid) in 85% yield. 1H NMR (400 MHz, CDCl3) δ 8.15 (s, 1H), 6.45 (t, J=54 Hz, 1H), 4.80-4.72 (m, 1H), 4.66 (dd, J=9.4, 3.0 Hz, 1H), 4.49-4.34 (m, 2H), 2.58 (s, 3H), 1.25 (s, 9H), 1.02 (d, J=6.5 Hz, 3H); MS m/z 362.3 (M+H)+; Rt-1.09 min. washed with saturated aqueous NaCl (2×20 mL) dried over Na2SO4 filtered concentrated

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

实验步骤: A solution of (R)-4-((R)-1-tert-butoxyethyl)oxazolidin-2-one (0.830 g, 4.43 mmol) and 2,4,6-trichloropyrimidine (0.894 g, 4.88 mmol, 1.10 equiv) in DMF (15 mL) was treated with NaH (60%, 0.248 g, 6.21 mmol, 1.40 equiv), then the resulting mixture (yellow) was stirred at room temperature for 1 h. The reaction mixture was diluted with EtOAc (100 mL) and quenched with saturated aqueous NaCl (100 mL). The layers were separated and the aqueous layer was extracted with ethyl acetate (2×30 mL). The combined organic layers were dried over Na2SO4, filtered and concentrated. Silica gel column chromatography (EtOAc/Heptane 0 to 40%) provided (R)-4-((R)-1-tert-butoxyethyl)-3-(2,6-dichloropyrimidin-4-yl)oxazolidin-2-one (1.0 g, white solid) in 69% yield. 1H NMR (400 MHz, CDCl3) δ 8.22 (s, 1H), 4.70-4.66 (m, 2H), 4.45-4.40 (m, 2H), 1.26 (s, 9H), 1.04 (d, J=6.6 Hz, 3H); MS m/z 334.0 (M+H)+; Rt-1.10 min. quenched with saturated aqueous NaCl (100 mL) The layers were separated the aqueous layer was extracted with ethyl acetate (2×30 mL) The combined organic layers were dried over Na2SO4 filtered concentrated

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 was added NaH (0.54 g, 13.5 mmol, 57% dispersion in mineral oil) to a solution of 2,4,6-trichloropyrimidine (1.22 ml, 10.6 mmol) and (R)-4-((R)-1-(tert-butoxy)ethyl)oxazolidin-2-one (1.8 g, 9.61 mmol) in DMF (32 mL) at 0° C. (ice bath) under a bubbler. The yellow suspension was then stirred at 0° C. for 15 min and then the ice bath was removed and reaction mixture allowed to stir 1 hr at room temperature. Reaction mixture was diluted with EtOAc and then carefully quenched with brine. The layers were separated and the aqueous layer was extracted with EtOAc. The combined organic layers were dried (Na2SO4), filtered and concentrated onto silica gel. Silica gel column chromatography (EtOAc/Heptane 0 to 100%) provided (R)-4-((R)-1-(tert-butoxy)ethyl)-3-(2,6-dichloropyrimidin-4-yl)oxazolidin-2-one (2.1 g, 6.28 mmol, 65% yield) as a white solid. 1H NMR (400 MHz, CDCl3) δ 1.04 (d, J=6.55 Hz, 3H) 1.26 (s, 9H) 4.38-4.48 (m, 2H) 4.64-4.75 (m, 2H) 8.22 (s, 1H). LCMS m/z 334.1 (M+H)+, Rt 1.10 min. the ice bath was removed reaction mixture to stir 1 hr at room temperature Reaction mixture carefully quenched with brine The layers were separated the aqueous layer was extracted with EtOAc The combined organic layers were dried (Na2SO4) filtered concentrated onto silica gel

反应条件: temp:27.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A solution of (R)-4-((R)-1-(tert-butoxy)ethyl)oxazolidin-2-one (5 g, 26.7 mmol) in DMF (50 mL) was cooled to −5° C. under N2 atmosphere. Internal temperature was monitored and maintained at ca. −5° C. during the portionwise addition of 60% NaH (1.28 g, 32 mmol) over 5 mins (no appreciable exotherm seen, but effervescence observed and cloudy suspension resulted). Added 2,4,5-trifluoropyrimidine (3.76 g, 28 mmol) dropwise whilst still maintaining the temperature at ca. −5° C. After complete addition the reaction mixture was stirred at this temperature for 15 mins before removing the cooling bath and allowing the rm to warm to room temperature (ca. 27° C. internal temp). Left stirring at room temperature for 6 h. Sampled reaction mixture and quenched with water, extracted into EtOAc; TLC and LCMS show significant product but remaining oxazolidinone sm. Cooled reaction mixture to 0° C. and added an additional portion of trifluoropyrimidine (1.2 g, 8.95 mmol), warmed to room temperature and left stirring for 3 h at rt. Still faint residual sm seen by TLC of sample, but quenched reaction mixture at this point. Workup: [Safety Note: NaF salt present. Do not acidify workup] Quenched the reaction mixture with water (100 mL) which resulted in considerable effervescence. Added EtOAc (75 mL) and separated, extracted the aqueous with EtOAc (2×75 mL), combined the organics, washed with water (100 mL), brine (50 mL), dried (MgSO4) and concentrated to dryness to give crude product as a pale yellow oil. Crude was purified by silica gel chromatography (initial neat DCM, then ramp to 20% EtOAc/DCM). Pure product fractions were combined and concentrated to dryness to give a colourless oil which was placed under high vacuum. Upon standing the oil converted into a white solid. 1H NMR (400 MHz, CDCl3) δ 8.47 (dd, J=3, 1 Hz, 1H); 4.73-4.68 (m, 1H); 4.62-4.52 (m, 2H); 4.34-4.28 (m, 1H); 1.20 (s, 9H); 1.11 (d, 3H). MS m/z 302.1 (M+H)+. cloudy suspension resulted) After complete addition the reaction mixture before removing the cooling bath Left stirring at room temperature for 6 h Sampled reaction mixture quenched with water extracted into EtOAc Cooled reaction mixture to 0° C. warmed to room temperature left stirring for 3 h at rt quenched reaction mixture at this point Quenched the reaction mixture with water (100 mL) which resulted in considerable effervescence Added EtOAc (75 mL) and separated extracted the aqueous with EtOAc (2×75 mL) washed with water (100 mL), brine (50 mL) dried (MgSO4) concentrated to dryness to give crude product as a pale yellow oil Crude was purified by silica gel chromatography (initial neat DCM concentrated to dryness to give a colourless oil which

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

实验步骤: To a solution of (R)-4-((R)-1-(tert-butoxy)ethyl)oxazolidin-2-one (6.35 g, 33.9 mmol) in DMF (170 mL) under a nitrogen atmosphere at 0° C. was added sodium hydride (2.14 g, 50.9 mmol, 60%) portion wise over 3 minutes. The reaction mixture was then stirred for 2 hr at 0° C. whereupon 2,4,5-Trifluoropyrimidine (5 g, 37.3 mmol) was added and the reaction mixture allowed to stir 75 minutes at 0° C. then the mixture was allowed to warm to RT and stirred for 1 hr at RT. The reaction mixture was quenched with the slow addition of saturated solution of NH4Cl and the aqueous mixture extracted with EtOAc. Organic phases combined, washed with water, brine, dried (Na2SO4), filtered and concentrated onto silica gel. Silica gel column chromatography (EtOAc/Heptane 0 to 50%) provided a colorless oil of (R)-4-((R)-1-(tert-butoxy)ethyl)-3-(2,5-difluoropyrimidin-4-yl)oxazolidin-2-one (6.97 g, 23.1 mmol, 68% yield) which crystallizes upon standing. 1H NMR (400 MHz, CDCl3) 1.10 (d, J=6.26 Hz, 3H) 1.18 (s, 9H) 4.25-4.35 (m, 1H) 4.49-4.62 (m, 2H) 4.65-4.73 (m, 1H) 8.45 (d, J=1.57 Hz, 1H). LCMS m/z 246.1 (-t-butyl fragment) (M+H)+, Rt 0.91 min. was added to warm to RT stirred for 1 hr at RT The reaction mixture was quenched with the slow addition of saturated solution of NH4Cl the aqueous mixture extracted with EtOAc washed with water, brine dried (Na2SO4) filtered concentrated onto silica gel

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

实验步骤: Sodium hydride (60% dispersion in mineral oil, 23 mg, 0.58 mmol, 1.2 equiv) was added to a solution of methyl 2,6-dichloropyrimidine-4-carboxylate (100 mg, 0.483 mmol) and (R)-4-((R)-1-(tert-butoxy)ethyl)oxazolidin-2-one (90 mg, 0.483 mmol, 1 equiv) in DMF (2.4 mL) at 0° C. The suspension was stirred at 0° C. for 1 hour, by which time it turned yellow. The reaction was quenched with dilute aqueous sodium chloride (20 mL) and extracted with ethyl acetate (2×20 mL). The combined extracts were dried over Na2SO4, filtered and concentrated. Silica gel column chromatography (EtOAc/Heptane) separated the regioisomers and provided methyl 6-((R)-4-((R)-1-(tert-butoxy)ethyl)-2-oxooxazolidin-3-yl)-2-chloropyrimidine-4-carboxylate (0.111 g, white solid) in 64% yield. 1H NMR (400 MHz, CDCl3) δ 8.79 (s, 1H), 4.76 (m, 1H), 4.69 (dd, J=9.4, 2.7 Hz, 1H), 4.52-4.41 (m, 2H), 4.02 (s, 3H), 1.26 (s, 9H), 1.05 (d, J=6.6 Hz, 3H). MS m/z 358.2 (M+H)+; Rt-1.00 min. The reaction was quenched with dilute aqueous sodium chloride (20 mL) extracted with ethyl acetate (2×20 mL) The combined extracts were dried over Na2SO4 filtered concentrated Silica gel column chromatography (EtOAc/Heptane) separated the regioisomers

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

实验步骤: A solution of (R)-4-((R)-1-tert-butoxyethyl)oxazolidin-2-one (0.100 g, 0.534 mmol) and 4-chloro-6-(difluoromethyl)-2-(methylthio)pyrimidine (0.124 g, 0.587 mmol, 1.10 equiv) in DMF (2.7 mL) was treated with NaH (60%, 0.026 g, 0.64 mmol, 1.20 equiv), then the resulting mixture (yellow) was stirred at room temperature for 30 min. The reaction mixture was diluted with EtOAc (20 mL), washed with saturated aqueous NaCl (2×20 mL), dried over Na2SO4, filtered and concentrated. Silica gel column chromatography (EtOAc/Heptane 0 to 40%) provided (R)-4-((R)-1-tert-butoxyethyl)-3-(6-(difluoromethyl)-2-(methylthio)pyrimidin-4-yl)oxazolidin-2-one (0.164 g, white solid) in 85% yield. 1H NMR (400 MHz, CDCl3) δ 8.15 (s, 1H), 6.45 (t, J=54 Hz, 1H), 4.80-4.72 (m, 1H), 4.66 (dd, J=9.4, 3.0 Hz, 1H), 4.49-4.34 (m, 2H), 2.58 (s, 3H), 1.25 (s, 9H), 1.02 (d, J=6.5 Hz, 3H); MS m/z 362.3 (M+H)+; Rt-1.09 min. washed with saturated aqueous NaCl (2×20 mL) dried over Na2SO4 filtered concentrated

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

实验步骤: A solution of (R)-4-((R)-1-tert-butoxyethyl)oxazolidin-2-one (0.830 g, 4.43 mmol) and 2,4,6-trichloropyrimidine (0.894 g, 4.88 mmol, 1.10 equiv) in DMF (15 mL) was treated with NaH (60%, 0.248 g, 6.21 mmol, 1.40 equiv), then the resulting mixture (yellow) was stirred at room temperature for 1 h. The reaction mixture was diluted with EtOAc (100 mL) and quenched with saturated aqueous NaCl (100 mL). The layers were separated and the aqueous layer was extracted with ethyl acetate (2×30 mL). The combined organic layers were dried over Na2SO4, filtered and concentrated. Silica gel column chromatography (EtOAc/Heptane 0 to 40%) provided (R)-4-((R)-1-tert-butoxyethyl)-3-(2,6-dichloropyrimidin-4-yl)oxazolidin-2-one (1.0 g, white solid) in 69% yield. 1H NMR (400 MHz, CDCl3) δ 8.22 (s, 1H), 4.70-4.66 (m, 2H), 4.45-4.40 (m, 2H), 1.26 (s, 9H), 1.04 (d, J=6.6 Hz, 3H); MS m/z 334.0 (M+H)+; Rt-1.10 min. quenched with saturated aqueous NaCl (100 mL) The layers were separated the aqueous layer was extracted with ethyl acetate (2×30 mL) The combined organic layers were dried over Na2SO4 filtered concentrated

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 was added NaH (0.54 g, 13.5 mmol, 57% dispersion in mineral oil) to a solution of 2,4,6-trichloropyrimidine (1.22 ml, 10.6 mmol) and (R)-4-((R)-1-(tert-butoxy)ethyl)oxazolidin-2-one (1.8 g, 9.61 mmol) in DMF (32 mL) at 0° C. (ice bath) under a bubbler. The yellow suspension was then stirred at 0° C. for 15 min and then the ice bath was removed and reaction mixture allowed to stir 1 hr at room temperature. Reaction mixture was diluted with EtOAc and then carefully quenched with brine. The layers were separated and the aqueous layer was extracted with EtOAc. The combined organic layers were dried (Na2SO4), filtered and concentrated onto silica gel. Silica gel column chromatography (EtOAc/Heptane 0 to 100%) provided (R)-4-((R)-1-(tert-butoxy)ethyl)-3-(2,6-dichloropyrimidin-4-yl)oxazolidin-2-one (2.1 g, 6.28 mmol, 65% yield) as a white solid. 1H NMR (400 MHz, CDCl3) δ 1.04 (d, J=6.55 Hz, 3H) 1.26 (s, 9H) 4.38-4.48 (m, 2H) 4.64-4.75 (m, 2H) 8.22 (s, 1H). LCMS m/z 334.1 (M+H)+, Rt 1.10 min. the ice bath was removed reaction mixture to stir 1 hr at room temperature Reaction mixture carefully quenched with brine The layers were separated the aqueous layer was extracted with EtOAc The combined organic layers were dried (Na2SO4) filtered concentrated onto silica gel

反应条件: temp:27.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A solution of (R)-4-((R)-1-(tert-butoxy)ethyl)oxazolidin-2-one (5 g, 26.7 mmol) in DMF (50 mL) was cooled to −5° C. under N2 atmosphere. Internal temperature was monitored and maintained at ca. −5° C. during the portionwise addition of 60% NaH (1.28 g, 32 mmol) over 5 mins (no appreciable exotherm seen, but effervescence observed and cloudy suspension resulted). Added 2,4,5-trifluoropyrimidine (3.76 g, 28 mmol) dropwise whilst still maintaining the temperature at ca. −5° C. After complete addition the reaction mixture was stirred at this temperature for 15 mins before removing the cooling bath and allowing the rm to warm to room temperature (ca. 27° C. internal temp). Left stirring at room temperature for 6 h. Sampled reaction mixture and quenched with water, extracted into EtOAc; TLC and LCMS show significant product but remaining oxazolidinone sm. Cooled reaction mixture to 0° C. and added an additional portion of trifluoropyrimidine (1.2 g, 8.95 mmol), warmed to room temperature and left stirring for 3 h at rt. Still faint residual sm seen by TLC of sample, but quenched reaction mixture at this point. Workup: [Safety Note: NaF salt present. Do not acidify workup] Quenched the reaction mixture with water (100 mL) which resulted in considerable effervescence. Added EtOAc (75 mL) and separated, extracted the aqueous with EtOAc (2×75 mL), combined the organics, washed with water (100 mL), brine (50 mL), dried (MgSO4) and concentrated to dryness to give crude product as a pale yellow oil. Crude was purified by silica gel chromatography (initial neat DCM, then ramp to 20% EtOAc/DCM). Pure product fractions were combined and concentrated to dryness to give a colourless oil which was placed under high vacuum. Upon standing the oil converted into a white solid. 1H NMR (400 MHz, CDCl3) δ 8.47 (dd, J=3, 1 Hz, 1H); 4.73-4.68 (m, 1H); 4.62-4.52 (m, 2H); 4.34-4.28 (m, 1H); 1.20 (s, 9H); 1.11 (d, 3H). MS m/z 302.1 (M+H)+. cloudy suspension resulted) After complete addition the reaction mixture before removing the cooling bath Left stirring at room temperature for 6 h Sampled reaction mixture quenched with water extracted into EtOAc Cooled reaction mixture to 0° C. warmed to room temperature left stirring for 3 h at rt quenched reaction mixture at this point Quenched the reaction mixture with water (100 mL) which resulted in considerable effervescence Added EtOAc (75 mL) and separated extracted the aqueous with EtOAc (2×75 mL) washed with water (100 mL), brine (50 mL) dried (MgSO4) concentrated to dryness to give crude product as a pale yellow oil Crude was purified by silica gel chromatography (initial neat DCM concentrated to dryness to give a colourless oil which