Sodium Azide → tert-Butyl 12-amino-4,7,10-trioxadodecanoate

Participants

Reaction Steps

NaN3 (35 g, 538 mmol) was added to a stirring solution of 3-{2-[2-(2-tosylsulfonyloxy-ethoxy)-ethoxy]-ethoxy}-propionic acid tert-butyl ester (20 g, 46 mmol) in DMF (150 mL) and the reaction was stirred overnight. Reaction was diluted with water (200 mL) and extracted with EtOAc (4×100 mL). The organic layer was washed with water (100 mL) and brine (100 mL) and dried over Na2SO4. The solvent was removed in vacuo to give an oil. Column chromatography EtOAc/Hex (1:4) gave an oil which corresponds to the 3-{2-[2-(2-azido-ethoxy)-ethoxy]-ethoxy}-propionic acid tert-butyl ester, (M+1)=304. This oil was hydrogenated using Pd (5% on carbon) in EtOAc under hydrogen (1 atm.) over 3 days. The catalyst was removed by filtration and solvent removed in vacuo to give an oil corresponding to the title compound, (M+1)=278.

Provenance & Evidence