右旋聚乳酸

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

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

实验步骤: To a solution of diisopropylamine (10.1 mL, 71.8 mmol) in anhydrous THF (50 mL) is added n-butyllithum (33.6 mL of an 1.6M in hexane) dropwise at 0° C. After 30 min at 0° C., 4-methyl-2-(methylthio)pyrimidine (5 mL, 35.9 mmol) is added. The resulting mixture is stirred at 0° C. for 30 min. After the addition of methyl isobutyrate (4.3 mL, 37.7 mmol) at 0° C., the reaction mixture is stirred overnight. The reaction mixture is quenched with acetic acid at 0° C., diluted with water, and extracted with ethyl ether. The organic layer is dried over sodium sulfate and concentrated in vacuo. The residue is purified by flash chromatography (SiO2, EtOAc/heptane 7:93 to 40:60) to give 4.3 g of 3-methyl-1-(2-methylsulfanyl-pyrimidin-4-yl)-butan-2-one. the reaction mixture is stirred overnight The reaction mixture is quenched with acetic acid at 0° C. diluted with water extracted with ethyl ether The organic layer is dried over sodium sulfate concentrated in vacuo The residue is purified by flash chromatography (SiO2, EtOAc/heptane 7:93 to 40:60)

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

实验步骤: To a solution of diisopropylamine (12.6 mL, 89.9 mmol) in anhydrous THF (50 mL) is added n-butyllithum (42.2 mL of an 1.6M in hexane) dropwise at 0° C. After 30 min at 0° C., 2-fluoro-4-methylpyridine (5 g, 45 mmol) is added. The resulting mixture is stirred at 0° C. for 30 min. After the addition of methyl isobutyrate (5.4 mL, 47.3 mmol) at 0° C., the reaction mixture is stirred overnight. The reaction mixture is quenched with acetic acid at 0° C., diluted with water, and extracted with ethyl ether. The organic layer is dried over sodium sulfate and concentrated in vacuo. The residue is purified by flash chromatography (SiO2, EtOAc/heptane 7:93 to 60:40) to give 4.8 g of 1-(2-fluoro-pyridin-4-yl)-3-methyl-butan-2-one as a light yellowish solid. the reaction mixture is stirred overnight The reaction mixture is quenched with acetic acid at 0° C. diluted with water extracted with ethyl ether The organic layer is dried over sodium sulfate concentrated in vacuo The residue is purified by flash chromatography (SiO2, EtOAc/heptane 7:93 to 60:40)

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

实验步骤: To N-isopropylcyclohexylamine (5.96 ml) in THF (30 ml) was added dropwise n-BuLi (1,6-M, 22.7 ml) at -78° C., and the mixture was stirred for 30 min, to which a THF (5 ml) solution of methyl isobutyrate (3.43 g) was added, and stirred at -78° C. for 45 min. Then, a HMPA (6.3 ml) solution of 1-iodo-4-methoxy-butane (9.05 g) was added to the mixture, and stirred at room temperature for 1 h to give methyl 2,2-dimethyl-6-methoxycaproate (4.81 g, 85%) after usual work-up. was added stirred at room temperature for 1 h

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

实验步骤: A solution of n-butyllithium in hexane (224 ml; 2.2M) was added to tetrahydrofuran (THF, 300 ml) at -60° followed by diiospropylamine (52 g) and this mixture was then warmed to room temperature stirred for 5 min and then cooled to -72° C. Methylisobutyrate (50 g) was then slowly added and the mixture was stirred for 11/2 hr at -70° C. Freshly distilled ethyl vinyl ketone (42 g) in THF (60 ml) was added to the above mixture over 10 min and the mixture was then stirred for a further 1/2 hr at -60° C and subsequently at room temperature for 2 hr. cooled to -72° C the mixture was stirred for 11/2 hr at -70° C the mixture was then stirred for a further 1/2 hr at -60° C and subsequently at room temperature for 2 hr