内消旋-1,4-二氯-2,3-丁二醇

反应条件: temp:0.00; pressure:0.00; stir:

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

实验步骤: A three-neck 500-mL flask equipped with a thermometer, a mechanical stirrer, an addition funnel, a condenser, and a positive nitrogen atmosphere was charged with 1,4-dichloro-2,3-butanediol (50.0 g, 0.314 mole), trioxane (9.43 g, 0.314 mole), and 1,2-dichloroethane (EDC) (300 mL). The 1,4-dichloro-2,3-butanediol was not totally dissolved. Concentrated sulfuric acid (46.3 g, 0.455 mole) was then added dropwise over eight minutes. During the addition period, a slight exotherm was noticed and the flask was immersed in an ice bath to maintain the reaction temperature at 21.5° C. to 25.5° C. for 2.1 hours. The reaction mixture was permitted to settle overnight. The acid layer was removed, washed once with 30 mL EDC, and discarded. The combined EDC solutions were quenched with 2% NaHCO3 (600 mL), washed with deionized water (400 mL), 1% NaHCO3 solution (400 mL), deionized water (400 mL, twice), and stripped in vacuo. The resulting light yellow liquid weighed 48.9 g (89.5% yield), and contained 1.8% EDC and 98.2% dl- and meso-(4,5-dichloromethyl)-1,3-dioxolane, as determined by GC analysis and proton NMR (CDCl3) δ (s, --OCH2O--), 4.1 (m, ClCH2CHCHCH2Cl), 3.6(d, ClCH2CHCHCH2Cl). A three-neck 500-mL flask equipped with a thermometer, a mechanical stirrer, an addition funnel, a condenser During the addition period the flask was immersed in an ice bath to maintain the reaction temperature at 21.5° C. to 25.5° C. for 2.1 hours The acid layer was removed washed once with 30 mL EDC The combined EDC solutions were quenched with 2% NaHCO3 (600 mL) washed with deionized water (400 mL), 1% NaHCO3 solution (400 mL), deionized water (400 mL

反应条件: temp:0.00; pressure:0.00; stir:

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

实验步骤: A three-neck 500-mL flask equipped with a thermometer, a mechanical stirrer, an addition funnel, a condenser, and a positive nitrogen atmosphere was charged with 1,4-dichloro-2,3-butanediol (50.0 g, 0.314 mole), trioxane (9.43 g, 0.314 mole), and 1,2-dichloroethane (EDC) (300 mL). The 1,4-dichloro-2,3-butanediol was not totally dissolved. Concentrated sulfuric acid (46.3 g, 0.455 mole) was then added dropwise over eight minutes. During the addition period, a slight exotherm was noticed and the flask was immersed in an ice bath to maintain the reaction temperature at 21.5° C. to 25.5° C. for 2.1 hours. The reaction mixture was permitted to settle overnight. The acid layer was removed, washed once with 30 mL EDC, and discarded. The combined EDC solutions were quenched with 2% NaHCO3 (600 mL), washed with deionized water (400 mL), 1% NaHCO3 solution (400 mL), deionized water (400 mL, twice), and stripped in vacuo. The resulting light yellow liquid weighed 48.9 g (89.5% yield), and contained 1.8% EDC and 98.2% dl- and meso-(4,5-dichloromethyl)-1,3-dioxolane, as determined by GC analysis and proton NMR (CDCl3) δ (s, --OCH2O--), 4.1 (m, ClCH2CHCHCH2Cl), 3.6(d, ClCH2CHCHCH2Cl). A three-neck 500-mL flask equipped with a thermometer, a mechanical stirrer, an addition funnel, a condenser During the addition period the flask was immersed in an ice bath to maintain the reaction temperature at 21.5° C. to 25.5° C. for 2.1 hours The acid layer was removed washed once with 30 mL EDC The combined EDC solutions were quenched with 2% NaHCO3 (600 mL) washed with deionized water (400 mL), 1% NaHCO3 solution (400 mL), deionized water (400 mL

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

实验步骤: A three-neck 5-mL flask fitted with a thermometer, mechanical stirrer, addition funnel, condenser and positive nitrogen atmosphere was charged with EDC (200 mL), isobutyraldehyde (11.3 g, 0.157 mole), and 1,4-dichloro-2,3-butanediol (25.0 g, 0.157 mole). Concentrated sulfuric acid (23.2 g) was added dropwise to the agitated mixture over thirty minutes, during which time a slight exotherm was noticed and the flask was immersed in an ice bath to maintain a reaction temperature of 17°-19° C. Stirring was then continued at ambient temperature (20° C.) for five hours. A three-neck 5-mL flask fitted with a thermometer, mechanical stirrer, addition funnel, condenser and positive nitrogen atmosphere the flask was immersed in an ice bath to maintain a reaction temperature of 17°-19° C was then continued at ambient temperature (20° C.) for five hours

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

实验步骤: A three-neck 500-mL flask equipped with a thermometer, a mechanical stirrer, an addition funnel, a condenser, and a positive nitrogen atmosphere was charged with 1,4-dichloro-2,3-butanediol (50.0 g, 0.314 mole), trioxane (9.43 g, 0.314 mole), and 1,2-dichloroethane (EDC) (300 mL). The 1,4-dichloro-2,3-butanediol was not totally dissolved. Concentrated sulfuric acid (46.3 g, 0.455 mole) was then added dropwise over eight minutes. During the addition period, a slight exotherm was noticed and the flask was immersed in an ice bath to maintain the reaction temperature at 21.5° C. to 25.5° C. for 2.1 hours. The reaction mixture was permitted to settle overnight. The acid layer was removed, washed once with 30 mL EDC, and discarded. The combined EDC solutions were quenched with 2% NaHCO3 (600 mL), washed with deionized water (400 mL), 1% NaHCO3 solution (400 mL), deionized water (400 mL, twice), and stripped in vacuo. The resulting light yellow liquid weighed 48.9 g (89.5% yield), and contained 1.8% EDC and 98.2% dl- and meso-(4,5-dichloromethyl)-1,3-dioxolane, as determined by GC analysis and proton NMR (CDCl3) δ (s, --OCH2O--), 4.1 (m, ClCH2CHCHCH2Cl), 3.6(d, ClCH2CHCHCH2Cl). A three-neck 500-mL flask equipped with a thermometer, a mechanical stirrer, an addition funnel, a condenser During the addition period the flask was immersed in an ice bath to maintain the reaction temperature at 21.5° C. to 25.5° C. for 2.1 hours The acid layer was removed washed once with 30 mL EDC The combined EDC solutions were quenched with 2% NaHCO3 (600 mL) washed with deionized water (400 mL), 1% NaHCO3 solution (400 mL), deionized water (400 mL

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

实验步骤: A three-neck 500-mL flask equipped with a thermometer, a mechanical stirrer, an addition funnel, a condenser, and a positive nitrogen atmosphere was charged with 1,4-dichloro-2,3-butanediol (50.0 g, 0.314 mole), trioxane (9.43 g, 0.314 mole), and 1,2-dichloroethane (EDC) (300 mL). The 1,4-dichloro-2,3-butanediol was not totally dissolved. Concentrated sulfuric acid (46.3 g, 0.455 mole) was then added dropwise over eight minutes. During the addition period, a slight exotherm was noticed and the flask was immersed in an ice bath to maintain the reaction temperature at 21.5° C. to 25.5° C. for 2.1 hours. The reaction mixture was permitted to settle overnight. The acid layer was removed, washed once with 30 mL EDC, and discarded. The combined EDC solutions were quenched with 2% NaHCO3 (600 mL), washed with deionized water (400 mL), 1% NaHCO3 solution (400 mL), deionized water (400 mL, twice), and stripped in vacuo. The resulting light yellow liquid weighed 48.9 g (89.5% yield), and contained 1.8% EDC and 98.2% dl- and meso-(4,5-dichloromethyl)-1,3-dioxolane, as determined by GC analysis and proton NMR (CDCl3) δ (s, --OCH2O--), 4.1 (m, ClCH2CHCHCH2Cl), 3.6(d, ClCH2CHCHCH2Cl). A three-neck 500-mL flask equipped with a thermometer, a mechanical stirrer, an addition funnel, a condenser During the addition period the flask was immersed in an ice bath to maintain the reaction temperature at 21.5° C. to 25.5° C. for 2.1 hours The acid layer was removed washed once with 30 mL EDC The combined EDC solutions were quenched with 2% NaHCO3 (600 mL) washed with deionized water (400 mL), 1% NaHCO3 solution (400 mL), deionized water (400 mL