Reaction #1265354

Reaction equation

Sodium hydroxide

benzoyl chloroformate

compound 5

{2-[2-(2-{2-[2-(2-Amino-ethoxy)-ethoxy]-ethoxy}-ethoxy)-ethoxy]-ethoxy}-acetic acid tert-butyl ester

→

compound 6

{2-[2-(2-{2-[2-(2-Benzyloxycarbonylamino-ethoxy)-ethoxy]-ethoxy}-ethoxy)-ethoxy]-ethoxy}-acetic Acid Tert-butyl Ester

Solvents

water

ethyl acetate

Conditions

Workup

1. 1
   ConcentrationThe reaction mixture was concentrated in vacuo, water (20 mL)
2. 2
   workup.ADDITIONwas added
3. 3
   Extractionthe slurry was extracted with CH2Cl2 (3×100 mL)
4. 4
   Washthe combined organic solutions were washed with saturated aq. NaHCO3 (20 mL) and brine (20 mL)
5. 5
   Dryingdried over anhydrous MgSO4
6. 6
   ConcentrationThe solution was concentrated in vacuo
7. 7
   Washeluted with CH2Cl2:MeOH 100:1 to 10:1 (v/v)

Procedure

Sodium hydroxide (2.0 mL of a 3M in water, 6.0 mmol) and benzoyl chloroformate (0.52 mL, 0.36 mmol) were added in portions to compound 5 (0.90 g, 2.3 mmol) in ethyl acetate (10 mL) and the resulting mixture was stirred overnight. The reaction mixture was concentrated in vacuo, water (20 mL) was added, and the slurry was extracted with CH2Cl2 (3×100 mL), and the combined organic solutions were washed with saturated aq. NaHCO3 (20 mL) and brine (20 mL), and dried over anhydrous MgSO4. The solution was concentrated in vacuo and the residue was loaded onto a silica gel gravity column (100 g) and eluted with CH2Cl2:MeOH 100:1 to 10:1 (v/v) to afford compound 6 as a colorless oil (0.93 g, 76%).

Source