Reaction #6718

Reaction equation

alcohol

6-{2-[2-(2-{2-[2-(2-hydroxyethoxy)ethoxy]ethoxy}-ethoxy)-ethoxy]-ethoxy}-hexanoic acid ethyl ester

Triethylamine

methanesulfonyl chloride

→

compound 20

Yield 85.4%

6-{2-[2-(2-{2-[2-(2-methylsulfonylethoxy)ethoxy]ethoxy}-ethoxy)-ethoxy]-ethoxy}-hexanoic acid ethyl ester

Yield 85.4%

Solvents

dichloromethane

Conditions

Workup

1. 1
   Temperaturethe mixture was chilled in an ice bath
2. 2
   workup.WAITat room temperature for two hours
3. 3
   FiltrationThe reaction mixture was filtered through silica gel
4. 4
   Otherto remove the triethylammonium chloride
5. 5
   Washthe filtrate was washed successively with water, saturated NaHCO3, water and brine
6. 6
   DryingThe organics were dried over Na2SO4
7. 7
   Filtrationfiltered
8. 8
   Concentrationconcentrated in vacuo
9. 9
   OtherThe residue was purified by column chromatography (silica gel, 9/1 ethyl acetate/methanol)

Procedure

The non-polydispersed alcohol 19 (0.835 g, 1.97 mmol) was dissolved in 3.5 ml dry dichloromethane and placed under a nitrogen atmosphere. Triethylamine (0.301 ml, 0.219 g, 2.16 mmol) was added and the mixture was chilled in an ice bath. After two minutes, the methanesulfonyl chloride (0.16 ml, 0.248 g, 2.16 mmol) was added. The mixture was stirred for 15 minutes at 0° C., then at room temperature for two hours. The reaction mixture was filtered through silica gel to remove the triethylammonium chloride, and the filtrate was washed successively with water, saturated NaHCO3, water and brine. The organics were dried over Na2SO4, filtered and concentrated in vacuo. The residue was purified by column chromatography (silica gel, 9/1 ethyl acetate/methanol) to give non-polydispersed compound 20 as a clear oil (0.819 g, 83%). FAB MS: m/e 503 (M+H).

Source