4-(2-aminoethyl)-1,3-dioxolan-2-one

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of the diol (9 g, 37.66 mmol) in CH2Cl2 (200 mL) was added triethylamine (15.2 g, 151 mmol) at −20˜30° C. under N2. After several minutes, triphosgene (5.5 g, 18.83 mmol) was added to the mixture dropwise at this temperature and stirred at −20˜30° C. for half an hour. Then the mixture was stirred at room temperature for 15 h. TLC (CH2Cl2/MeOH=10:1) showed the starting material was almost consumed. To the mixture was added water and extracted with ethyl acetate. The organic layer was dried over anhydrous Na2SO4, concentrated under vacuum and purified through silica gel chromatography (CH2Cl2/MeOH=10:1) to give the corresponding cyclized dioxolane (6.5 g, 55%) as pale solid. After several minutes Then the mixture was stirred at room temperature for 15 h was almost consumed To the mixture was added water extracted with ethyl acetate The organic layer was dried over anhydrous Na2SO4 concentrated under vacuum purified through silica gel chromatography (CH2Cl2/MeOH=10:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of the diol (9 g, 37.66 mmol) in CH2Cl2 (200 mL) was added triethylamine (15.2 g, 151 mmol) at −20˜30° C. under N2. After several minutes, triphosgene (5.5 g, 18.83 mmol) was added to the mixture dropwise at this temperature and stirred at −20˜30° C. for half an hour. Then the mixture was stirred at room temperature for 15 h. TLC (CH2Cl2/MeOH=10:1) showed the starting material was almost consumed. To the mixture was added water and extracted with ethyl acetate. The organic layer was dried over anhydrous Na2SO4, concentrated under vacuum and purified through silica gel chromatography (CH2Cl2/MeOH=10:1) to give the corresponding cyclized dioxolane (6.5 g, 55%) as pale solid. After several minutes Then the mixture was stirred at room temperature for 15 h was almost consumed To the mixture was added water extracted with ethyl acetate The organic layer was dried over anhydrous Na2SO4 concentrated under vacuum purified through silica gel chromatography (CH2Cl2/MeOH=10:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of the diol (9 g, 37.66 mmol) in CH2Cl2 (200 mL) was added triethylamine (15.2 g, 151 mmol) at −20˜30° C. under N2. After several minutes, triphosgene (5.5 g, 18.83 mmol) was added to the mixture dropwise at this temperature and stirred at −20˜30° C. for half an hour. Then the mixture was stirred at room temperature for 15 h. TLC (CH2Cl2/MeOH=10:1) showed the starting material was almost consumed. To the mixture was added water and extracted with ethyl acetate. After several minutes Then the mixture was stirred at room temperature for 15 h was almost consumed To the mixture was added water extracted with ethyl acetate