2,2-二氟-3-羟基丙酸乙酯

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

实验步骤: Dihydropyrane (2 ml, 22 mmol) was added to a solution of ethyl 2,2-difluoro-3-hydroxypropionate (3.1 g, 20 mmol) and pyridinium p-toluene sulfonate (0.25 g, 1 mmol) in anhydrous dichloromethane (50 ml). The mixture was stirred overnight at room temperature and the desired compound ethyl 2,2-difluoro-3-tetrahydropyranyloxypropionate was obtained by flash chromatography on silica gel (ethyl acetate:hexane; 15:85) (4 g, 80%).

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

实验步骤: A mixture of paraformaldehyde (4.5 g, 50 mmol), ethyl difluorobromoacetate (10.2 g, 50 mmol) and activated zinc dust (3.3 g, 40 mmol) in anhydrous tetrahydrofuran was heated under reflux for 0.5 h. Then the mixture was treated with a saturated aqueous solution of ammonium chloride and extracted with diethyl ether. After usual work-up the desired compound ethyl 2,2-difluoro-3-hydroxypropionate was obtained by flash chromatography on silica gel (ethyl acetate:hexane; 25:75) (4.1 g, 53%). was heated under reflux for 0.5 h extracted with diethyl ether

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

实验步骤: Dihydropyrane (2 ml, 22 mmol) was added to a solution of ethyl 2,2-difluoro-3-hydroxypropionate (3.1 g, 20 mmol) and pyridinium p-toluenesulfonate (0.25 g, 1 mmol) in anhydrous dichloromethane (50 ml). The mixture was stirred overnight at room temperature and the desired compound ethyl 2,2-difluoro-3-tetrahydropyranyloxypropionate was obtained by flash chromatography on silica gel (ethyl acetate:hexane; 15:85) (4 g, 80%).

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

实验步骤: A mixture of paraformaldehyde (4.5 g, 50 mmol), ethyl difluorobromoacetate (10.2 g, 50 mmol) and activated zinc dust (3.3 g, 40 mmol) in anhydrous tetrahydrofuran was heated under reflux for 0.5 h. Then the mixture was treated with a saturated aqueous solution of ammonium chloride and extracted with diethyl ether. After usual work-up the desired compound ethyl 2,2-difluoro-3-hydroxypropionate was obtained by flash chromatography on silica gel (ethyl acetate:hexane; 25:75) (4.1 g, 53%). was heated under reflux for 0.5 h extracted with diethyl ether

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

实验步骤: Dihydropyrane (2 ml, 22 mmol) was added to a solution of ethyl 2,2-difluoro-3-hydroxypropionate (3.1 g, 20 mmol) and pyridinium p-toluene sulfonate (0.25 g, 1 mmol) in anhydrous dichloromethane (50 ml). The mixture was stirred overnight at room temperature and the desired compound ethyl 2,2-difluoro-3-tetrahydropyranyloxypropionate was obtained by flash chromatography on silica gel (ethyl acetate:hexane; 15:85) (4 g, 80%).

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

实验步骤: A mixture of paraformaldehyde (4.5 g, 50 mmol), ethyl difluorobromoacetate (10.2 g, 50 mmol) and activated zinc dust (3.3 g, 40 mmol) in anhydrous tetrahydrofuran was heated under reflux for 0.5 h. Then the mixture was treated with a saturated aqueous solution of ammonium chloride and extracted with diethyl ether. After usual work-up the desired compound ethyl 2,2-difluoro-3-hydroxypropionate was obtained by flash chromatography on silica gel (ethyl acetate:hexane; 25:75) (4.1 g, 53%). was heated under reflux for 0.5 h extracted with diethyl ether

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

实验步骤: Dihydropyrane (2 ml, 22 mmol) was added to a solution of ethyl 2,2-difluoro-3-hydroxypropionate (3.1 g, 20 mmol) and pyridinium p-toluene sulfonate (0.25 g, 1 mmol) in anhydrous dichloromethane (50 ml). The mixture was stirred overnight at room temperature and the desired compound ethyl 2,2-difluoro-3-tetrahydropyranyloxypropionate was obtained by flash chromatography on silica gel (ethyl acetate:hexane; 15:85) (4 g, 80%).

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

实验步骤: A mixture of paraformaldehyde (4.5 g, 50 mmol), ethyl difluorobromoacetate (10.2 g, 50 mmol) and activated zinc dust (3.3 g, 40 mmol) in anhydrous tetrahydrofuran was heated under reflux for 0.5 h. Then the mixture was treated with a saturated aqueous solution of ammonium chloride and extracted with diethyl ether. After usual work-up the desired compound ethyl 2,2-difluoro-3-hydroxypropionate was obtained by flash chromatography on silica gel (ethyl acetate:hexane; 25:75) (4.1 g, 53%). was heated under reflux for 0.5 h extracted with diethyl ether

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

实验步骤: Dihydropyrane (2 ml, 22 mmol) was added to a solution of ethyl 2,2-difluoro-3-hydroxypropionate (3.1 g, 20 mmol) and pyridinium p-toluenesulfonate (0.25 g, 1 mmol) in anhydrous dichloromethane (50 ml). The mixture was stirred overnight at room temperature and the desired compound ethyl 2,2-difluoro-3-tetrahydropyranyloxypropionate was obtained by flash chromatography on silica gel (ethyl acetate:hexane; 15:85) (4 g, 80%).

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

实验步骤: A mixture of paraformaldehyde (4.5 g, 50 mmol), ethyl difluorobromoacetate (10.2 g, 50 mmol) and activated zinc dust (3.3 g, 40 mmol) in anhydrous tetrahydrofuran was heated under reflux for 0.5 h. Then the mixture was treated with a saturated aqueous solution of ammonium chloride and extracted with diethyl ether. After usual work-up the desired compound ethyl 2,2-difluoro-3-hydroxypropionate was obtained by flash chromatography on silica gel (ethyl acetate:hexane; 25:75) (4.1 g, 53%). was heated under reflux for 0.5 h extracted with diethyl ether